imagine going to a 19th century physicist and telling them that 21st century physics is plagued by enormous nigh-unsolvable philosophical questions - but that we're also unsatisfied because our theories break down "only" before 10-³² seconds after the beginning of the universe
@@starofcctv94 lol yeah and the fact we know that is entirely mundane to us. the big debate is actually what happened before the beginning. which we somehow have ideas about, with evidence, despite that definitely seeming impossible.
@@monkatraz Correct me if I'm wrong but aren't we basically making assumptions based on certain observations (red shift etc) and mathematically working backwards to end up with the "beginning" or "big bang" scenario? It's heavily possible given our current understanding that we've missed something crucial, especially given the limits of what parts of the universe we can actually (or will ever even be able to) see.
@@paulpesci1 We are, but our assumptions are very reasonable and the evidence that the universe used to be ludicrously smaller (aka the big bang) is overwhelming. It's hard to interpret what we see out there as anything else, even if we question our assumptions.
This actually sounds like how I often run games of dnd. The players enter somewhere, a place I have yet to fully design. Then, as the players ask questions "is this room well lit?", "how far away is the next door", "can I climb this wall?", it forces me to choose the nature of the location. Only because the players asked did the room become how it is now! With that analogy, I now imagine the universe being asked by scientists "how does this work?" and the universe stuttering as it poorly explains a property, as the scientists fervently write notes.
This is how I design D&D puzzles. I just come up with the puzzles, I never design a solution. I let my players do that. If it sounds at all feasible, it works.
this is awesome! thanks for sharing the insight. But I don't get how the scientists' fervently writing notes corresponds to the choosing of a location. Could you explain?
This reads like a scientist living his own Lovecraftian horror story. Knowledge so unknowable that one begins to go insane from a sudden intuitive understanding that they can't put into words because the words don't exist. But the fright and despair in the eyes of the afflicted is so intense that you can only shudder at the thought of such a horrifying realization
You ever experience an emotion you couldn’t quite pin down with words? I definitely think there is a limit on what we’re able to communicate with each other verbally; it’s why languages have so many words-to feel infinite when they really aren’t
@@bitterlemonboy you hit the nail on the head. I think something we ALL experience to some degree is having a very complex, detailed, or involved thought... And you just can't say it in a way that will communicate the concept fully. It can be a terrible feeling, but if you learn to temper it, you can find that sweet balance between what you say and what you don't. Believe it or not, it's not about what you say but rather what you TRY to say. Every effort works you towards a direction, with various effects as a result. So I may verbally say one thing, but whatever I was REALLY trying to say will effect how I automatically think in the future. It's complicated, of course, no concept can be full said, but different levels of general overview can be given, and each level can help better the understanding of those who understand it.
The mass of the entire universe in a black hole producing the size equal to our cosmological event horizon was such a cliffhanger. Please elaborate on this next time.
The aspects of this sort of quantum observer effect that most interest me are when the interactions occur over vast distances. Ten billion years ago, some galaxy near the edge of our own observable universe emitted a photon into deep space. This photon didn't just go in one direction, but according to QM 'rippled' outwards like a wave, potentially interacting with countless octillions of other particles along the way. The ripple expanded outwards in many directions, through nebulae, planets, other stars, probably other telescopes belonging to aliens *outside our observable universe* and by chance it didn't interact with any of them, passing over all of them without a blip - until one day that wave - now 20-billion light-years wide - suddenly resolved as a discrete ping on the CCD of the Hubble Telescope. The photon who's position was indeterminate for over 10-billion years, possibly anywhere within our observable universe or well outside it, suddenly was THERE for just a moment, and likewise there may have been an instantaneous entangled quantum interaction with the electron responsible for emitting that photon so long ago - even though the galaxy from which it came is probably now far beyond our particle horizon. Equally interesting, as photons move at the speed of light and thus do not experience time, that interaction was - from its standpoint, if it could be said to have one - instantaneous.
I love how you put it. This is mind-blowing. I actually had the idea of quantum observer in mind as the video rolled in, before that interpretation was suggested, and I was thinking every interaction defines reality, but then how could it be true in light of the delay induced by the half-reflecting mirror experiment. Well I don't think what you said fixes that problem but it's still interesting to think about
@@trifonTAF Yeah. I'm still trying to wrap my head around the particulars of that experiment and how it describes interactions. Don't feel like I have a good grasp of it yet.
Makes you wonder how much of a 'flow' of photons/waves there is from a star. Are there staccato gaps or are these photon/waves a constant unbroken output.
as you state yourself: the answer lies in there being no time from the photon's point of view. Hence its apparent feedback of time-reversed choice while interacting with its environment. Not only is space and time relative and undividable from each other, so are the 'act' of measurement and its apparent influence. The cause and effect relationship only makes sense when there is no actual time, because if time needs to be reversed for it to make sense over long distances, one should seriously start to doubt how crippled our experience of time actually is.
When I started watching this channel I thought a career in fusion was a pipe dream. Now I've worked on a research device and will be working on SPARC. Plasma physics is a deep field but it's very interesting. Please do videos on it!
Our BIG BANG is just one of trillions of other BIG BANGS at unimaginable distances. (Actually Infinite big bangs is a truer fact). SPACE HAS NO END AND TIME NEVER ENDS (Both also had no beginning) Once your brain finds this to be a TRUE statement your half way to understanding the theory of EVERYTHING. In the mean time I want this guy to go inside my coffin while I shoot it with a machine gun. He likes the "cat in the box theory" so he should put his money where my lead is. Dark energy is a near infinite mass of ice cold neutrons that exists in between galaxies and our big bang is surrounded by billions of other DEAD Big Bangs now COLD and with only neutrons that gather to form the next big bang at a critical mass where MASS is converted into pure ENERGY AGAIN and again and again and never in the same place twice. A big bang life cycle is about 500 to 900 trillion years depending on the materials surrounding the DARK SINGULARITY (a Black hole with the mass of a big bang.) This makes all big bangs about the same size since the critical mass is always the same to create 9th Dimensional matter or a Neutron Crystal devoid of all heat (Zero energy with unimaginable mass) There is your strange "Dark Matter" simple neutrons and lots of them. Lots of mass but no light, no energy, pure dead matter with no Pauli-exclusion principle at work, no heat or voids = NO ELECTRONS between the NEUTRONS at all! \psi = probability amplitude that electron 1 is in state a and electron 2 is in state b \psi_{1}(a) = probability amplitude that electron 1 is in state a \psi_{2}(b) = probability amplitude that electron 2 is in state b Dark matter /psi state is ZERO electrons and only pure cold neutrons.
The thing about the 2 entangled particles which somehow communicate at a distance, even a distance of light-years, gives a good clue to the underlying nature of everything. The laws of symmetry: rotational, displacement in space and time etc all connected to conservation laws like conservation of angular momentum and momentum etc. Now the measured particle with spin “up” “causing” a distant entangled particle to have spin “down” happens because the law of conservation must be obeyed, even if things are light-years apart. So, it also tells us that the information about the up and down spins is more fundamental than distance. Therefore, we have evidence of an underlying informational universe more fundamental than our apparent physical universe. That much is clear.
For what i'have come to know, the entanglement effect stipulate only an _associative relation_ between two particle at distance, so it would be that the particle [x] is _related_ to the particle [y]: it would be impossibile for a "comunication" to happen because it would violate the generally accepted principle of special relativity (light- velocity is the max velocity in the universe). For a comunication between particles to take place, the information exchanged would have to travel faster than light, and since it is know to be not possible there has been proposed the "non-comunication theorem" that conserve both this qm phenomena and the coherence in the relativity framework.
No one considers how many of the particles on earth are already entangled, by their very nature of coexistence on the same 'material plane' Which means we are all already entangled with each other at the quantum level. What's more DNA itself is normally in a Ball shape, and works as an antenna Then there's the Schumann Resonance, and Morphic Waves... and the temporally retroactive influence of Quantum Wave collapse at point of observation. What's more that would mean we are already a single Superorganism, working like a Galactic Brain in a State of Self Consciousness Observation of itself A Singular Plurality
Being a big fan of both science and philosophy, these episodes make me so happy. I wish I could have learned more about this in high school. Then the intrinsic uncertainty of the Universe wouldn’t have felt so problematic, but rather the natural state of things.
@@bronchialaktivbalsam3830 Well, status, money and a nice work environment are drivers that steers the most qualified people. We could actively work to push a bigger slice of the pie towards teachers and the system that backs them up. It requires the very brightest to explain complicated stuff at the right level.
Thank you Mark Evans for supporting the channel!! Im a young entry level engineer not making much but I feel obligated to donate and support after watching this channel for so long. Never stop PBS Space Time !
I think there is plenty of space in the field of physics for philosophers. Science currently only measures the physical aspect of the universe but there is clearly something more that we are missing and I think having philosopher physicists working on finding new ways to think of these problems is extremely helpful for the field as a whole to grow. We may not be able to measure consciousness now but maybe it will be these philosopher physicists who find some way to do so in the future!
Amanda Gefters book “Tresspassing in Einstein’s Lawn” covers this whole topic, and Wheeler’s contributions to it in a lot of depth. It’s an amazing and lovely book.
Hi Matt, long time viewer, and thank you for presenting Wheeler's interpretation. I am not a physicist, but for years I always thought of the delayed choice experiment as follows: since light does not experience time, there is no such thing as "delayed choice" for the photons. From their perspective, the different configurations of the experiment simply eliminate possibilities, and the photons end up in a superposition of the remaining possibilities that are consistent with the configurations. Sorry if my interpretation is overly naive. That's why I will keep watching your show. Thank you, and please keep them coming.
the -20 questions game is also used in the book "consciousness explained" to describe at first, iirc, how dreams arise, and extended later to be a more general theory of how conscious experience in general arises. interesting, the parallel thinking about two seemingly very different subjects.
I dont believe that consciousness is required for reality. That would mean theres nothing beyond the observable universe, because we can never interact with it and never will be able to interact with it. And we're pretty sure thats not true. Theres likely stuff outside the observable universe. Also, we know of a time before life on Earth. It had to exist, because we're here, but nothing was conscious.
Reality and consciousness could be like SpaceTime in which as Einstein put it they are different aspects of the same thing Meaning there is a connection between but we aren't aware of how the connection works or even what type of connection it is
As I watch more and more videos about quantum mechanics, I am further convinced of the idea that the wave function is the universe's way of implementing lazy loading for optimization. For clarity, lazy loading is the programming principle where resources or objects are not initialized until they are actually utilized.
But does it not take more work to calculate both probabilities especially when both possibilities interfere with each other like in the double slit experiment? Does not seem very efficient or lazy to me.
@@H4XO5 Depends whether the bottleneck is in calculating the information or loading it. Since transmitting classical states requires production and interaction of photons, thermodynamics might make it preferable for the universe to have 'zero-particle' information transmission via waveform collapse, if you want to subscribe to Copenhagen, or state-checksum pass, if you want to subscribe to Everett. Not sure where Bohmian mecanics would fall in this example.
That doesn't really make sense. Imagine two particles that are in their own respective superpositions suddenly interacting. Lazy loading implies loading resources on demand, in this case the state of the particle, but how would the universe/particle know *when* to load this resource (in this case, the state to which the superposition collapses to) if neither particle is doing any calculation before the interaction? If the universe doesn't care in which state either particle is before interaction and they are in that undefined superposition to save computing resources on the state of the particles, then how would it know when to actually start computing their definitive states when the demand is created by the interaction, how do you keep track that such an event is fired? And how would the algorithm decide on a definitive set of states in the interaction if both of its inputs are undefined? You're still doing additional computation in the background to keep track when this occurs and you need actual data as input to make a decision, so there is no real optimization in anything. The idea seemingly makes sense because you're only thinking of one side of the interaction, but both particles participate in the interaction, it'd be like having two sleeping threads suddenly waking each other up by themselves which doesn't work, at least one has to be awake or you need a third one that keeps track when to wake both of them up to do the calculation. No real performance boost there either way.
It is appealing but consider, what would a program be without a computer. If you compare the universe to a computer code you are assuming that the universe exists inside some sort of closed state computer which runs it? I don't believe that to be so. It would be like saying because the universe contains light it is like a camera capturing light also.
In the days of Newton, when the marvels of Europe were clocks, scientists tended to think of the universe as a giant clock, with planets going round in regular orbits. In the information age, when computers are the preeminent technology, we have an urge to think of reality as digital or a simulation. How do we know we're not making the same mistake again?
One of the greatest videos I have ever seen. Similar feeling to when I first studied philosophy and Buddhism and learned that many of my own ideas had been explored and organised into theories by people long before me. This makes me feel a lot more comfortable in the absolute abyss of this questioning. Happy to be here and be a part of history - whether this is all an illusion or some big answers come our way soon ❤
I'd be interested in hearing your take on Penrose's idea that if the universe ends up decaying entirely into massless particles, then the notion of space collapses and you have a universe's worth of energy in a no-space, which would provide the initial conditions for a big bang. Sort of an oscillating universe theory, except without any collapse.
Perhaps a series on "Why QM and GR disagree" some lead up episodes getting down how the equations have problems mixing, progressing into how hypothetical GUT's get around or attempt to fix these issues and the subsequent issues with those theories and their predictions beyond whats needed? This may be a tad too math oriented as that's the main sticking points for the two otherwise it would be easy haha. But anything like that would definitely be helpful in getting a bigger picture of what cutting edge physics is dealing with. Cheers!
There are non-mathematical, conceptual ways to think about the problem. A big part of it comes down to time: Relativity establishes that time is a mutable dimension tied to space, whereas quantum mechanics treats time in the "classical" way of an immutable background on which processes can be measured. In short, under quantum mechanics, spacetime doesn't bend, which makes it unhelpful in understanding what happens at the particle level when spacetime is strongly bent according to relativity.
It’s less that they disagree, rather that one works on one scale, and the other works on another scale. The issue is we have no idea how, when, or why the transition occurs from micro to macro. The closest we have is coherent quantum wave function super positioning, and objective wave function collapse. Which leaves us with more questions than answers.
@@badlydrawnturtle8484 but can’t we do qft on curved space times? isn’t the problem just that we don’t have a good model of how the curvature follows from superposed matter?
@@kashu7691 It's more fundamental than that. Quantum models assume that time is separate from space; they're built upon fundamentally different assumptions from general relativity, which takes space and time to be a four-dimensional manifold. This is why the problem is so difficult; the underpinning notions of how space and time operate are incompatible. It's not as simple as finding some neat mathematical links to tie them together: One of them is necessarily, fundamentally, WRONG.
@@badlydrawnturtle8484 QM is fundamentally wrong. Super positions and waveforms don't exist, they are just a fudge for an unanswered question. The cat is not dead and alive, it's either decomposing or really pissed off. Perform the experiment, and leave it running for 1 year, I bet that the answer will always return a dead cat, proving that the super position theory is a fantasy. We may not know the exact moment that the cat died, but that does not mean it was dependent on being observed or interacted with.
The universe may or may not be creating itself, but what IS definitely happening is that the Universe is aware and trying to understand itself - by the sole fact that we humans are part of the universe. I just think that's amazing - that an entity that bursts forth from a amorphous plasma and evolves to learn about itself.
I've agreed with the idea that "observation" is "interaction" for a while - I know NdGT has struggled to explain that to the public for some time. But the experiment described in this video raises a question - how does the reflection off a mirror/beamsplitter not count as an interaction that would collapse the wave function, but the measuring device does? Surely reflecting photons involves particle/particle interactions, so I don't understand how superposition survives that interaction. What's the real line in the sand here that constitutes a meaningful interaction?
I struggle to make sense of the question of when a quantum measurement occurs without invoking decoherence. The wavefunction didn't collapse in the first beamsplitter because it didn't decohere with the external environment (unlike when it interacted with the measurement apparatus after the second splitter).
I believe the beam splitters are carefully manufactured so that they're very regular, and so can interact with the wave function in the desired way without completely scrambling it. As for what counts as an interaction that would collapse the wave function? That depends on your interpretation of quantum mechanics. According to the interpretation presented in this video, it would only collapse when observed. So if humans are observers and measuring devices aren't, then even interactions with the latter wouldn't collapse the wave function. However, Wheeler doesn't specify what counts as an observer, so it could be that measuring devices count and do indeed collapse the wave function. The Copenhagen interpretation (the first and most commonly taught one) just says that the collapse happens at some point, but there's no generally agreed upon point. Presumably it would happen at some point between the moment the photon hits the receptor, and the moment conscious observers process the results. Other interpretations argue there's no collapse at all though, like Pilot Wave Theory and Many-Worlds. In Many-Worlds (my favorite personally), the wave function instead gets scrambled as it starts encompassing more components of the measuring device and the surrounding environment, and so it stops meaningfully interfering with itself, whereas it could when only the beam splitter was included. This is the process known as decoherence. So in that interpretation, the observer doesn't collapse the wave function. They just become part of it, but can't interact with the other outcomes because the whole system is now too complex. There's not a lot of practical ways to falsify any interpretation, so that's why it's hard to definitively say what happens. It's mostly a philosophical debate for now. Look up "measurement problem" if you want to know more :)
I think some "interactions" do not permit measurement, i.e. the beam splitter splits the beam, but has no method to know how the beam was split. So whichever outcome (path A vs path B) the beam splitter is completely identical, and no information on where the photon went is left with the beam splitter. If you somehow modified the beam splitter to measure it, then the wave function would "collapse" due to the disturbance. Though to be honest, I am not sure, since I would think even a single photon, with no change in it's energy (frequency), but it's altered direction would have a different momentum, which would be 'felt' by the mirror, and therefore observable.. though perhaps the change is so small it doesn't constrain the photon wave function enough to collapse it to a 'classical' measurement (the mirror just gets entangled into it's own superposition??). Ok I definitely don't understand QM lol Also, for a real laser/beam splitter set up, some fraction of the photons would be absorbed by the beam splitter and slightly heat up the material, but in that case that is a measurement, and the result is the photon doesn't take either path A or B..
Thanks for your challenging and interesting dives into QM, GR, etc. I'm an astrophysicist by training and a systems engineer by occupation, and you have helped my understanding of a number of complex topics that I'd wondered about. Please keep up the good work.
the thing is that observation is fundamentally impossible without interaction. We see things because they reflect photons. So observation without interaction doesn't make sense in any context really
But not all interactions?.. In the delayed choice experiment photons are deflected by mirrors and it doesn't matter in the end. How is interaction in the detector different from interaction with mirrors?
Physicality in this context doesn't make any sense. An electron has to be observed to collapse to cause electromagnetic forces to repel. What do you mean by physical interaction exactly?
I mean this is probably the best TH-cam channel in our universe for people who love questions and want to imagine. Thank you PBS for making me a better student and for sharing all your passion for physics with the world. I honestly don't know if this message will ever be found by anyone in a universe of information that may or may not be partially created by our observation. Again thanks for inspiring me. P.S. As I stare at the universe, the universe stares at me. I don't know if this phrase means anything but I like how it sounds!
Yes it does, one day we will look up into the stars and say "why look that's me" We are the big bang. All of everything came as a result, we are the evolution of the Universe itself. You are never alone because the universe is you.
Yea i always wonder what the world would be like if channels like this, pbs eons, moth light media, sci show, crash course, sci show space... etc... were popular as tiktok... what the world would be like.
As an anthropology student strongly engaging with ideas drawn from phenomenology I find this debate within physics the most exciting by far I have ever heard of.
If you rephrase the negative 20 questions as the "questions" being interference between different components of the universal quantum wave function, and the "answers" being positive interference, it seems to me that it basically has to be true that the "real universe" is just whatever is left when all of the other possibilities have been removed by destructive interference.
There's interesting parallels to this idea to be found within the physics of consciousness. The electromagnetic theory of consciousness posits that the waves of electromagnetic coherence that arise from the underlying electrochemical action of a brain's billions of synchronized firing neurons "carve" the quasi-stable patterns experienced as conscious phenomena into the relentless, impossibly chaotic and complex storm of background electromagnetic field activity. But achieving a sufficiently high SNR might not just be an amplifying function but also involve a process of destructive decoherence across the relevant ranges of the electromagnetic field within the space occupied by a brain. Given the brain's massive parallel processing architecture, such action would have the effect of serving as a naturally evolved form of error checking neurological information processing as incoherent information - likely indicating wrong/incorrect internal representations of the external world - would destructively interfere with each other, preventing both it from arising into conscious experience and providing a phenomenological feedback mechanism in the form of psychological discomfort we term cognitive dissonance. "Where did I leave my keys...?" *brain subconsciously evaluates numerous potential locations while recall functions attempt to recover the relevant memories such that potential locations not in coherence with what was partially recorded in memory interfere and are deamplified while the actual location constructively coheres with the low-fidelity memory recall function, amplifying that pattern sufficiently to generate a conscious experience of the keys being left at that location*
@@suchislife801 Sherlock was solving crime, not studying the universe lol. Both are plagued by human infallibility however. Can one possibly conceive of everything impossible in the first place?
the thing ive learned from myself, and other people, is that we often look for patterns, and in a desperate attempt to make sense of chaos, trick ourselves into seeing them for comfort.
This programme is keeping me awake, lol. I can't believe a better physicist to illustrate these concepts. This man is up there with Lenny Susskind. He doesn't care for the BS but does care physics is understood.
I think the cleanest view is that "collapse" is emergent from the web of entangled particles that make up the matter in the universe. Once there's enough particles whose wave functions are entangled, they constrain the wave functions of all the other entangled particles to the very narrow wave function that we associate with a classical piece of matter.
WTF?? How exactly does “collapse” emerge from entangled particles? Does your “collapse” also encompass non-matter particles, such as entangled photons? Why is there a distinction between the “collapse” of matter versus non-matter particles? Also, you do realise that collapse is a verb, not a noun, right? If so, how is it in any way possible for a verb to emerge from anything? This really doesn’t make any sense and seems rather illogical. And what is meant by “the” matter, is whatever you’re referring to somehow different from all other matter? If not, what’s the meaning of the word “the” preceding matter? You then go on to say that “enough particles whose wave functions are entangled” but you have no explanation of what constitutes “enough”, so exactly how many entangled particles are indeed “enough”? How does any entangled particle “constrain the wave functions of all other entangled particles”? In what way/how are said wave functions constrained? What then happens once a wave function has been constrained, how is it different from the wave function prior to this constraint and why exactly is it being constrained? Finally, what is this “very narrow wave function that we [please, speak for yourself, I most certainly am not to be included in your “we”] associate with a classical piece of matter”? Since when does anything “classical” have anything whatsoever to do with quantum processes? I’ve never heard of “very narrow wave function” which someone could “associate with a classical piece of matter”, how is said wave function derived? And what exactly is meant by “a classical piece of matter”? How small/large is your “classical piece of matter” and what’s meant by “piece of”? Matter isn’t usually considered as something which one can take a piece of, it’s more a generalisation for myriad elementary particles, atoms, nucleons, etc. So, to take a “piece of matter” isn’t something one would normally speak about. Even if you had simply said “classical matter” or better yet, just “matter”, this might be slightly easier to understand, but we’re splitting hairs here, I think. I am truly perplexed by your comment. It would be great to get some (actually, a lot of😊) clarification as to just what it is your cleanest view entails and how anything close to the usual meaning of the word collapse, in a quantum sense, could possibly be emergent from entangled objects, irrespective of whether they constitute matter or otherwise. And the processes by which the emergence occurs, what defines the number of “enough particles” (and who decides when enough is enough?)? So these particles which are entangled and are subsequently constraining “the wave functions of all other entangled particles”, are they constraining the wave functions of all other entangled particles in the entire universe, the visible universe, just the single particle with which another has been entangled or what, exactly? Last but not least, how wide or narrow are wave functions in general, regardless of whether said function is (somehow, perhaps in an abstract, non-intuitive way) associated with “a classical piece of matter”? And since the very definition of wave function is, in the generally accepted and most commonly used view/understanding/application is that it’s a mathematical description of the quantum state of an isolated quantum system. So how you can possibly try to associate a wave function with anything classical is an explanation and concept about which I’m most certainly looking forward to gaining some small amount of insight.
It took me many rewatches to fully grasp, but this concept is brilliant. It feels like it almost elevates the universe (or any extensive system) to the level of any observer, whether conscious or not.
It's like a dream where the dreamer is both the dreamer and the creator of the dream in a feedback loop. The only difference is dreams are fleeting, whereas waking reality persists and continues to build in a reasonably consistent way, until someone like Einstein comes along and says here's a crazy paradigm sift that fits, now let's go test it, and our view of realty completely shifts while also being completely consistent and measurable.
The concept of observation/interaction retroactively defining reality has always been really interesting to me, but not with quantum physics, instead, storytelling. Imagine this analogy: you're playing a video game, an RPG, and one of the characters asks what your player character's name is. You then get to choose your name, in that moment. But, within the story, that was *always* your character's name, for their whole life (presumably), and the only thing that happened there was that another person asked what it was. Furthermore, there may be countless other players out there with countless other playthroughs choosing different names, all equally retroactively true to their specific game, or, perhaps, universe, but equally none of their characters will have any way of knowing about yours.
That's a great point. It reminds me of the "Neverending Story" (the book, not the film). During his stay in Fantasia, Bastian can wish for anything to happen. For example, for a knight who's trying to prove his worth, he invents a dragon who keeps abducting virgins and enslaves them until they die, and then he sets out to capture a new one. This dragon has now captured the knight's lady, and he has to go on a quest to save her. So, is that saying that the moment that Bastian wished for this scenario to play out, there has actually been such a dragon all along, and that Bastian is responsible for the miserable lives of all the women he abducted before?
Yes but there is still the code version, an ultimate defining base version named [null] who does all posibilities and none simultaneously, until the player runs and interacts with the code, creating the save that defines the character's life. So in this analogy, we want to know the base code of the universe. the ultimate defining version that is all posibilities and [null] simultaneously. That's why we keep trying to figure out where the universe came from. Knowing where the game came from gives you an idea of where to ask for the code. What would be our equivalent of this?
I find the particles acting like a wave function untill an observer (conciousness) views it particularly interesting as it's more evidence for string theory if you ask me.. I think we are 3d beings in some 9-10d universe.
Man the reason this channel is better than most others is because it never ends the video unfinished: he always explores the subject satisfyingly fully
Fascinating! Wheeler's negative 20 questions reminds me of a Wordle variant called "Absurdle" which uses your guesses to narrow down the space of possibilities. It's maximumly challenging to get to an actual answer.
Haha, yes I also thought of Absurdle! Of course, the difference being that Absurdle is deterministic and picks the answer that gives the most options, while the universe 'randomly' picks from all possible answers, with weight given to more likely/possible answers.
I very much love the fact that our observation of reality meets ancient philosophy. In this video I was reminded to a nice buddhistic idea: The experienced object, the experiencer and the experience are the same. Please keep on making cool videos space time team!
I wonder if you fully understand that the word "we"means indicates or signifies the user of the term - that is you sunshine, and his immediate interlocutor, and since you have no immediate interlocutor, "we" can only indicate will be replaced with "I", or it is entirely imaginary. In the instant circumstances do you agree that you have no direct immediate interlocutor therefore when you refer to "we" you are phoned to yourself and absolutely nobody else whatsoever. Do you understand that? Why are you creatures so terrified of the perpendicular pronoun "I"? Why do you seek to hide behind some fantasy "we"?
if anybody wants to know what dogma looks like you can find a pretty clear image of it at 11:11 always fun to see modern physicalists contortion to refuse the logical idea that there exists only one consciousness in the universe, which would explain everything, but sounds too "mystical" for their dogma
This was truly a stellar episode, I'm absolutely certain it was one of the best. Thank you so much for giving me something to ponder. I'm not very well schooled, but I'm very curious, and your show always gives me such tantalizing thoughts to consider.
@Praise Jesus, Repent or Likewise Perish Thanks for sharing M, and its warms me to the cockles of my heart that you are saved in the blood of the lamb... but this is a conversation about physics... are we perhaps off our meds, or would you like to speak with someone about how Jesus and Quantum Mechanics are connected?
@@ChildOfTheLie96 I'm hoping this is the most hysterically sarcastic thing anyone has ever said... because if it's not, you've just invented the negative IQ. Which is actually impressive, besides dark matter, dark energy, and antimatter, the negative IQ poses serious physical questions; That if an observer with a negative IQ observes an event in the universe, do they de-collapse the wave function??? Inquiring minds....
Matt: We have determined that our universe is created from answering questions. Matt shortly later: Please answer our 8 question survey. Matt next episode: Physicists have just discovered 256 new universes.
In the game Oathlords, which you should play immediately, "God" is called the Dreamer and nothing exists until it dreams of it... or really imagines it. The elves are immortal because they were created before the Dreamer thought of death. The humans came just after. The universe began when the Dreamer first differentiated solid from ether, Erdfader and Etherdrottning, and liquid was formed in their embrace, water being associated with balance and life. But anyway... the universe is just an evolving awareness of possibilities which become realities.
I find it strange to present observation in terms of "conscious beings" *first,* and only then go back and consider the possibility that observation is just interaction. The latter seems vastly simpler and more coherent.
Apparently, the universe was around billions of years before “conscious beings “ existed. Indeed, interaction is the definition of observation, even in this video .
@@Boogaboioringale correct. The philosophical dilemma only exists if the observer is necessarily conscious. Which of course is absurd because that would necessarily require consciousness to somehow be supernatural.
Interaction between non-conscious objects, however, does not cause the collapse of the wavefunction. @Kerry Fitch The universe was around for billions of years only as per our observation collapsing it into such a state. We have no way of knowing what exists outside of our conscious experience and observation.
I don't know exactly when it started, probably somewhere around the Enlightenment, but science took a hard turn in trying to distance itself from God and thereby put humanity at its centre, as we and our senses are the instruments that scrutinize and measure the Universe. We can only know what we as human beings understand. This has its roots in Descartes, the guy who said "I think, therefor I am". This has been criticized by conservatives (ironically), but also by writers like Lewis Carroll (Alice in Wonderland) and H.P. Lovecraft (where humans' brains literally start melting or they go completely crazy by the sight of gods visiting Earth). For the Ancient Greeks, this was never questioned, because they saw science as a mere tool to improve their technology. However, modern society sought to replace Christianity with science, and this has created the society of experts we are rife with today. City planning, psychology, sociology, everything that can be mapped or turned into a logical system, will be, and our society relies on experts to solve these "problems" so someday, we can have heaven on earth. Slowly, through the quantum, God has come back into science. We are living in an age where Enlightenment is fading, because we have scientifically proven science cannot rid us of all our problems. There is no technocratic valhalla waiting for us, we simply have to deal with this Earth as it was given to us and respect its own laws that tie us to her. For the first time ever, there is mathematical proof that the optimism of science is mere philosophy. It portrays a version of reality that makes it easier to understand, but it is not reality itself. There are paradoxes, now perhaps even some that science cannot find a way out of, and some people are freaking out that their own set of logic has presented them with a paradox that cannot be solved. Let that sink down: a paradox that cannot be solved. Scientists cannot, and will not, accept science that contradicts itself, even if it is true. If you were trying to solve a paradox in philosophy, people would laugh at you. Paradoxes exist for you to learn and accept that your field is merely a representation of reality. Yet it is the fruit of science, technology, that makes scientists believe their way is the only way, and because technology is everywhere, people have come to accept this statement as well. They are absolute morons if they cannot accept science proves a lot of things, but not everything. The sooner you learn that, the sooner you can start to learn to understand the world with your heart and your soul instead of exclusively your mind. So consider yourself lucky for not having problems with such an easy question, because apparently there are a lot of people out there who have a really hard time dealing with that kind of stuff.
@@CommandoPootis "We have no way of knowing what exists outside of our conscious experience and observation." By that same reasoning, I have no reason to believe you are anything more than a single comment on the Internet that itself only popped into existence when I read it. If you want to be intellectually honest, you have to take it to its conclusion, which is to completely disbelieve in anything that you are not actively, directly observing, including any other consciousness, and deep suspicion of even what you observe because you might be hallucinating it. If that's the position you want to hold, feel free; but it's not a very useful one, and taking a little part of it while ignoring what the reasoning ultimately leads to is NOT consistent.
Have long felt this way about the universe. I wonder if the set of "questions" that can be asked by each physically real particle, A, is constrained by whatever interaction collapsed A to begin with. Say B is collapsed into a 4 by C asking "what is a number between 1 and 10". Now B can only ask "what is a number between 1 and 4", A answers by collapsing into a 2. This is a ropey analogy suggesting that electrons and photons are electrons and photons, because whatever collapses then to begin with can only "ask" a very narrow range of "questions", i.e the probability space is very tightly constrained by prior interactions. This may seems a little obvious, but then perhaps you can go far enough back to eventually define a singular interaction describing the big bang. In a pre-universe information space where all possible "questions" can be asked simultaneously, one of the "answers" will inevitably collapse into the universe we observe. As an aside, is it possible for a complex enough computational engine, fed information about other previous interactions, be able to further constrain the questions it can ask, in order to increase the likelihood of a particular answer. In other words, could a defining feature of consciousness be a weak form of "free won't", avoiding already "asked questions" in order to arrive closer to a preferred answer, on a macroscopic level.
You say narrow but you can argue numbers between 1-4 is infinite, the infinite bubble is smaller but still infinite. Which I think it is how the questions/answer pool is 3^n infinitely because there are 3 answers true, false, undefined (paradox perspective, ping pong contradictions) to one question. Even equivalence is not specific enough 1=1 can be true and false in an infinite number of ways by observational perspective changes
@@AskEpic well I guess that depends on whether reality, and/or the probability space for a given system, is infinitely divisible or discrete. Though I do want I say I used numbers as discrete integers for the purpose of this analogy, and didn't mean to imply real numbers with infinite values between each one. I should have used letters instead.
Does this have anything to do with particles travelling at the speed of light? My thinking is that since photons travel at the speed of light and thus have no experience of time, the "point-like" instance in which they exist needs to be completely defined before they can have any kind of meaningful properties. Does that make sense? Like, imagine a photon that existed some time right after the big bang, and is absorbed by a photon detector in the present day. From the photon's perspective, its entire existence from its reference frame is still a single instant from the time it was emitted to the time it was detected. But if the photon detector is removed, the photon still exists for a single instant, but that "instant" isn't defined yet because the photon hasn't been measured. There's no "end" to its journey yet, so it isn't "defined." Man all this stuff messes with my head, are there any physicists who can help?
Indeed. photons only take time to travel because it has interactions with any other particles in the universe. if it was literally alone in the universe, it would not experience ANY time at ALL. This made me realize something funny about time and gravity. Time slows down in gravity and it's said that it's time that causes gravity and not the other way around, you could say that time dilation is the universe literally slowing down the clock speed to calculate all the interactions without errors like a computer would :Þ The game EVE Online actually does this haha.
You need a physician, not a physicist. To deal with the headache, I mean. (BTW - I think part of the headache is that you can't really say that a photon has a "point-in-time-like" existence from the standpoint of an outside observer; that's only true from the point of view of the photon; if we moved at the speed of light, our consciousness would necessarily be very different, if it could exist at all)
This might be the essence of the wave function. Photons are in a state of "superposition" existing because of a future particle interaction making it's reference frame "defined", yet before measurement is still in a state of nonexistence since it's reference frame has not been "defined" yet. However, considering the fact that universe is expanding faster than light, some photons may be traveling through the void of space making the point of there existence never "defined. It would likely depend on whether or not photons are eternal.
Really interesting theory! I think that some of the issues with this (and many other quantum theories) is that some terms are not well defined: what exactly is an observer? A human? I sure hope so! A cat? Probably. A tree? Maybe, it can react to changes in it's environment. Is that observation? If so, almost everything is an observer! A bacteria? A virus? Even a chip in a computer reacts to it's (electrical) environment. And not just electrical if you hook up suitable sensors. Hopefully we can come up with a good scientific answer to this. And no one seems to know what consciousness is! It seems to me like these questions are tightly coupled with many of the attempts to interpret quantum mechanics beyond "shut up and calculate".
If 2 pebbles collide & 1 sustains a dent, is that considered a measurement or observation? If 2 particles collide & change trajectory, is *that* considered a measurement or observation? IMO that finally solves the q “what if consciousness had never existed”?
Consciousness (as in awareness not mental activities) is just when something’s state changes in response to information from its interaction with another thing, or better stated when something’s (object a) state is changed in from its interaction with another thing (object b) it gains information of that other thing (object b). When scaled up to neural networks which gather external information and synthesize it into a multidimensional matrix (as in there are many datapoints) that represents the outside world (our experience), it makes sense how consciousness derived from particle interactions. The things experiencing the information would be the particles that comprise the neurons which receive the information.
Tbh I don’t know why this channel so frequently focuses on outdated speculative woo no modern working physicist actually cares about. It’s not just “shut up and calculate”, it’s that when all you have is philosophy and thought experiments and can’t set up actual experiments to prove or disprove your points it ceases to be science. Einstein started with thought experiments to formulate and explain his ground breaking theories but eventually we moved on to countless empirical evidence those theories were right. What can’t be tested sooner or later gets discarded and for the little I know, some of the arguments that Matt presents to his audience as still fresh and relevant, have already been discarded a while ago.
This is reminiscent of "lazy execution" in computer science, where a piece of state is generated on-demand instead of being computed every time there's a change to the system. For example, a rectangle defined by two points on a 2D plane, where the object is manipulated by moving the points around, but every 100 manipulations or so the program needs to query the width of the rectangle. The object can store a "dirty" flag, which indicates that its remembered width is out-of-date. Any time there's a change to a point, it sets the dirty flag to true, then when the width is queried it checks the flag. If the flag is false then it returns the previously calculated value, but if the flag is true then it calculates the width, remembers it, and sets the flag to false, then returns the result of the query. This makes the query itself more expensive, but because the query only happens 1% as often as the manipulations, it results in an overall savings, since the width isn't constantly being recalculated when there's no use for it.
@@Nomadmandude You only need to store information about a pair of opposite corners. The other two corners can be inferred. Useful if trying to save space when storing, say, a trillion rectangles for some reason. If, going clockwise, corner A is at (4,10) and corner C is at (7,5), and that's all we know - we can infer the rest. This is a 3x5 rectangle (xA - xC, yA - yC). We can also determine corner B will have coordinates (xC,yA) and must be at (7,10) and corner D will be at (xA,yC) or (4,5). visual aid: www.desmos.com/calculator/geukrvlspu
We are living self-conscious processors of Information, in a Universe where everything is Information and Energy, and where, if there is a purpose, it could be characterised as “Information seeking understanding through experience”.
Well put. Do you think the Big Bang was “GOD” becoming aware of its own existence? (GOD being a stand-in for the ineffable ground of all being, be it trinity or flying spaghetti monster)
@@thelawfus I conceive of the Quantum Foam and Eternal Inflation as being like a pot of water simmering on a stove, with bubbles constantly forming. Physicists define the line between the finite Classical World and the infinite ‘Quantum Foam’ as ‘The Heisenberg Cut’. Our ‘Classical’ World, one of a myriad of ‘bubbles’, is defined by limited information (34 constants determine the standard models of Particle Physics, Classical Physics and Cosmolgy), constrained possibility, finite potential and one jolt of useable energy given by our ‘Big Bang’. Studies near ‘Absolute Zero’ show that the fundamental rule that necessitates space, the ‘Pauli Exclusion Principle’ disappears, and that matter can exist in a state of ‘Superposition’ (a ‘Bose-Einstein Condensate’) Absolute Zero is by definition the barrier where there is no motion. On the other side of ‘Absolute Zero’, as there is no motion, and there is no need for Space or Time: there is only ‘Pure Information’- existing in a Singularity of Superposition as a ‘Quantum Foam’. In Spiritual terms, a Supreme Consciousness: an emptiness, a void, outside of Space and Time. ‘Brahman’, ‘God’, ‘Nirvana’, Plato’s perfect forms and Spinoza’s Substance are all conceptual ways of trying to describe the same state.
@@thelawfus I'm thrilled to find this viewpoint somewhere else than in my own mind. Only that I had imagined the Big Bang as the universe achieving the peak of consciousness, thus "creating" GOD, who consequently created the basis for the universe's and thus his own existence. Assuming that time is non-fundamental, of course.
If we leave in a participatory Universe why the Univers creates the Aliens for us since we look so hard from them and we don't see and clue that they exist or existed whatsoever since we peer with out telescopes into the far reaches of space and time
Question: Under this interpretation, does this mean that photons should be thought more of like a probablistic constructive ray trace from point of measurement? (So the measurement builds the reality, not the reliaty causing the measurement) As in, in a extremely simple and young universe; the first measurement is made, it is that of a red photon, this in turn creates the possibility (however low) that one of the following, but not limited to, exists: -A thing that emits red photons all on its own -A thing that emits photons, that hit another thing that absobed it and emitted a red photon -A thing that emits blue photons, but is acceleating away so quickly the photon is red shifted -etc... And as more measurements are made, that support one of those possibilties, the more likely it is to exisit, and because they'll be interacting off eachother, existance will eventually come to a semi-'agreed' upon state?
This is very interesting indeed! There are some similarities to what computer science refers as "capabilities based computing" and your ideas. In a capabilities system, there are rules that all members follow (for example, the amount of energy needed to produce blue light) and the final state (the "reality") is constructed from the initial set of events given. In your example, only a single path of possibilities would be permitted and that would be what we observe. If you wish to understand capabilities a little more, I highly recommend looking for videos about "wave function collapse" for video games (totally unrelated to physics, it's more about constructing game maps from basic rules)
Hmm, your comment it making me think of another strange possibility. Maybe we are experiencing time backwards (what seems to be forwards to us)? Is it possible that the minimum entropy of the big bang is the final state of the universe? By looking up at the clear night sky, you are emitting photons perfectly towards the impending collapse of all things.
@@nsk370 well if the laws of nature are time symmetrical. Then it doesn't really matter whether we are guided towards minimum entropy or maximum entropy. As we experience time, to us it makes sense that we are heading towards maximum entropy. But that is just the way that time flows in our perspective. It could be that our time flow perspective is reversed from the true flow of time. Granted this is very far-fetched. And I definitely wouldn't place any bets on this idea.
Penrose mentioned in an interview with Peterson how there are observations with 99%+ confidence from earlier universes in the CMB. A couple of 'spots' from the Planck observatory iirc, and they would be the leftovers of supermassive black holes in the former universe. I cannot wrap my mind around this, please cover this in a video! 😍
The participatory universe theory gives further weight to the notion I’ve held most of my life which is that the universe is a ‘context’ that allows it to observe and experience its own endless possibilities. Or as Brian Cox would say - we are a means for the universe to come to know itself, an idea held by some cultures for thousands of years. The oldest ones are often the best 😊
Lovely man Brian Cox, and a dreadful dreamer and the funny thing about his dreams is that he supposes them to be something other than dreams.When a man supposes that an image that is *only* an image in his associative apparatus is something *other* than an image, he takes what is no more and no less than image to be that *of which* it is an image. That is surely axiomatic. It is exactly the same of words; men suppose that because they have the word they necessarily have the meaning or can directly immediately personally experience what for which the word is only a symbol. It simply does not necessarily and inexorably follow that because you have the word you necessarily have the meaning or corresponding direct immediate personal experience which exactly matches the word and the associations that that word evokes in your associative apparatus.To be perfectly brutal and blunt, that simply is *not true* or the case.The fact of the matter is that images and words obscure more than they reveal - it is unavoidable that is the case, because that is the whole*point* of them.They act as proxies.
woopie doo - an argument from someone maybe smarter than you gives a preexisted thought of yours "more weight". confirmation bias mixed with appeal to authority.
Kind of wish this would be more regularly couched by 'interaction' rather than observation. Despite the quantum 'fuzziness' of the existence of individual particles as they dash through the universe (or tabletop light beam experiments), most things WE experience have a much more significant and solid reality - because all the particles that make up us and our environment are interacting *constantly*, billions of times per second. This prevents any sort of 'quantum fuzzy woo' from cropping up in our lives, because all the stuff of us and our world is essentially pinned down by these interactions. Only when you get into rarefied experiments, or photons traveling endless light years through space does this sort of quantum observer/interaction weirdness generally become relevant. Honestly, Relativity already told us that interaction is critical to the underpinnings of reality - it's literally right there in the name - because you cannot define the properties of any particle EXCEPT as they relate to some other particle! That relationship and their interactions between each other are the actual important part. All forces and vectors are measurements between particles, not of particles. You can't even measure the mass of a particle in total isolation, because even mass is a relative value, as seen by the way particles can gain mass as they approach the speed of light.
Completely agree. It’s like they intentionally choose words that would mislead any lay person to think that consciousness determines reality instead of interaction, like you said.
I don't think we should confuse interaction with observation. Particles don't care if they're interacting or not, neither do they care if they're real or not. An observation is not just a measurement or a recording. It's the act of a sentient being perceiving an interaction or an effect and objectively reflecting on and reacting to it to predict the future. Self-reflexive consciousness is such a weird, crazy, exasperating phenomenon. It's not that the universe isn't real without conscious observers to perceive it, it's that the question is totally meaningless without any observers, because there's no one around to ask any questions in the first place. We can meaningfully question the nature of reality now with us around to observe it, but whether eg the universe was real before we were around to perceive it? Forget it, just shut up & calculate.
I watched the video, no need to timestamp anything. And obviously I’m not saying they are literally trying to mislead people, but they do intentionally use terms that inherently gatekeep this kind of info. The ONLY way to observe something is to interact with it, which is why they send particles down a vacuum in these experiments. But instead of stating “The particle is in a superposition until we interact with it,” they say “The particle seems to be in a superposition until we observe it.” This DIRECTLY leads to people putting an emphasis on consciousness rather than the interaction required for the observation. As for the timestamp, it demonstrates my point that he’s having to clarify what he DOESN’T mean when he could just use more accurate terminology.
It's marvelous seeing the convergence between the scientific study of physics and Buddhist cosmology. It makes you really appreciate how brilliant people must have been thousands and thousands of years ago.
How is it that the beam splitters from Wheeler's thought experiment (and real experiments like the quantum eraser) do not themselves lead to the collapse of the wave function? The photons must interact (or not) with the atoms at the beam splitter. When they do, the photon is absorbed and a new one comes out. Intuitively, it seems that the atoms of the beam splitter have measured which path the photon has taken.
There is clearly a matter-energy field wave medium that pervades space and photons are obviously a ball of compression energy that causes a field stretch that can reflect, refract, diffract and interfere with little or no loss of energy to the compressed energy ball focal point. -- The beam splitter always randomly reflects the focal point or lets it through, so a random path is always followed. The accompanying field warp / pilot wave is 50% reflected, 50% let through the splitter. When the extra splitter is put in place the diffracted, preceding field warp recombines with constructive interference, forming a wave guide that ensures the focal point always hits the same detector on the right hand side (going by the diagram in the vid), no matter which path the focal point took.. -- Double slit is similar. Preceding stretch-compression field warp / standing wave(let) is large and goes through both slits, diffracts and interferes, forming wave guides (rough and calm field)... The wavelet focal point only goes through the slit it is aimed at but only a tiny amount of quantum randomness is enough for the focal point to randomly hit a wave guide a follow it.. Putting another detector near one of the slits interferes with the wave guides so the focal point goes straight.
_"When they do, the photon is absorbed and a new one comes out"_ - the photons are not absorbed, and new photons are not emitted. The (QM probability) wave of the photon induces waves in the electrons of the material. And the induced waves then interact with the wave of the photon again, affecting the behaviour of the photon. See Fermilab's excellent explanation of why light refracts in glass: th-cam.com/video/NLmpNM0sgYk/w-d-xo.html, and think "probabilities waves", instead of the EM waves he talks about. But it touches on the main question: "when does the probability wave collapse", that is: "what is a measurement?". Or in this experiment: "why does the photon detector make a measurement, but the beam splitter not". The answer to that is not known yet.
@@renedekker9806 .. It is my variation of Pilot Wave Theory extended to the Quantum Eraser Experiment.. I've been pushing an Electro-Positronic Matter-Energy EM Field theory for years under the radar in forums... Electrons and Positrons are the only known proper permanent fundamental, elementary particles with definite intrinsic mass. -- Quarks have never been seen outside a Proton / Neutron. Many experiment results SHOULD lead to the conclusion that all compound proper matter is MOST LIKELY made only of electrons and positrons. If you want to discuss this you are welcome. -- A load of old +ve charge balls (field cells, quanta, base charge +1) close-packed by free-flowing, compressible, discplacible -ve 'gas' (Pixie Farts / Electron Gas).. It's a Realist, materialist, mechanical model with the electrostatic Coulomb force as it's one base force from which all other forces emerge.. It's a self-balancing field under tension. -- Many Standard Model variations are possible from this MOST SIMPLE FIELD possible from which to emerge Standard Models... My models stick to definite facts. I can explain phenomena possibilities using the model. Mainstream theoretical physics is deeply confused, that is a definite fact even they'll admit. Particle Entanglement and Photon 'entanglement' are very different in my main variation.. AC field vibrations in a 'flux tube' between charged particles vs what I described about QE and DS Experiments.. Wave Guides,
@@stopthephilosophicalzombie9017 it's mostly because we don't have any testable alternative theories. Up until very recently every experiment, at least in fundamental physics, has supported the current theories. For the holes we do have (dark matter, etc) no theory has been proposed which explains every experiment we already knows the results of, explains the phenomena we can't yet explain, and it's testable. Testability is probably the biggest issue. That's why we are trying to look farther in space and need bigger super colliders as these will allow more detailed experiments and observations.
The delayed choice experiment ceases to perplex if you consider Relativity. The time elapsed from a photon's creation to its demise, from the photon's perspective, is always zero. From the photon's point of view, the decision of how to behave, and the measurement, happen the same instant. Has the delayed choice experiment been repeated with slower particles?
yes, De Broglie showed that any quantum effect also works with the other particles and can be extended to packets of them, up to regular objects. The effects even out, and that's where quantum becomes classic, but only gradually so, although in discrete steps.
@@scififan698 I know that experiments like the double-slit have been done with slower particles. I still think it would be a good thing to verify delayed choice with slower particles, though, to rule out once and for all the relativistic angle. But I'm not a physicist; just an interested bystander.
The fact that experiments like the double-slit experiment is repeatable with particle that have mass shows they are also in a superposition of states and that there's nothing particularly special about photons in that regard. This in turn suggests there is no reason for us to believe particles with mass would behave any differently the delayed choice experiment.
This episode reminded me, strongly, of when I first read Wittgenstein's 'On Certainty'--that we enter into a language game to build shared understanding (agreement) of a thing. Philosophical skepticism, then, actually can be addressed. To suggest that a "reality" may emerge from us course-correcting our way toward a shared 'something' via our inquiries makes sense. That path is legitimate when facing genuinely 'wicked' and complex problems.
I’m convinced that we are the result of an infinite imagination where nothing makes sense until we try to make sense of it. Much like our brains make sense of random thoughts that somehow coalesce into a dream reality.
One interesting thing I'd like to note is that this seems to map precisely onto a similar question in mathematics: Are we creating new mathematics, or are we discovering already existing maths? The answer seems to be roughly similar, too.
Philosopher Alan Watts puts it much more succinctly: We see the universe not as it is but as WE are. Consciousness in the present moment is the basic reality, it plays with itself by making up stories about its own existence. The past emanates from the present the way a wake emanates from a boat-- it shows us where we've been but does not propel us forward.
I‘m a mathematician, and I struggle hard to get a straight answer from physicists on the following questions: 1. given an observation, how do you calculate forward or backward the wave function in time? Is that even meaningful? 2. Is it fair to compare quantum mechanics to a hidden Markov model if you replace the Markov transition operator with some unitary operator and the emission operator with the absolute square of a projection? If 2. is the case, then in my mind, the mystery would basically go away. If you think about it, a hidden Markov model is (just like a Markov chain) just an encoding of the statistics of the observable marginal process. Often, the hidden process is entirely made up and just serves to reduce the complexity of the data to something that we can deal with mathematically. The same might be true for the wave function: even though you kinda need it to effectively calculate the statistics of quantum measurements, it may be entirely made up. Note that one doesn’t have to treat mathematics as „just a language“ or say that physical models are always „just models [that don’t say anything about fundamental reality]“. One only has to know when to make this distinction. If my speculation is correct, we might learn something about fundamental reality by analyzing the class of observable processes that quantum mechanics encodes. However, I wouldn’t expect efficient predictive algorithms from that.
Physicist here. So for point one: the "collapse" of the wavefunction, or in other words the measurement of the wavefunction in a specific basis with a specific outcome, is a non-unitary process; you can inherently not calculate backwards. Calculating forwards is straightforward given the state into which the system was projected; this is done according to Schrödinger's equation. As to point 2, I'm personally not familiar with the emission operator, but a relatively recent theory paper has proven that only a theory using so-called "local hidden variables" could produce a more complete description of the world than quantum theory. I think this is what you refer to by "hidden model"? The Wikipedia page about hidden variable theory is quite informative.
I'm no physicist but even I can tell you the answer to the first one, time symmetry alone can be broken, in fact only CPT symmetry appears to always hold, meaning some events are physically different going forwards or backwards in time, once you add causality into the mix you have a clear arrow and distinction between forwards and backwards in time. An example of time symmetry being broken can be found in the flavour oscillation of B-mesons.
@@TheBmannumber1 Although the result of wavefunction collapse is non-unitary, the time reversal function of the time dependent equation is anti-unitary is it not? So depending on your interpretation of the question posed there is meaning to solving backwards in time, no?
I struggle with the following… since photons travel at the speed of light, they dont experience time, so by measuring/interacting with it, we modify its whole existance… its not that the wave function is collapsing, its that the object/wave has been interacted with, modifying its whole existance?
@@TheBmannumber1 In the theory of HMMs, calculating backward isn’t achieved with a transition matrix (the classical analogon) either. It’s an entirely different process known as „conditioning“ or recursively applying the „Bayes‘ rule“. I know about Bell‘s refutation of local hidden variables in a classical statistical setting. I‘m not interested in a such a classical theory, but I would like to understand is if one can generalize inference rules to a quantum setting, or possibly even beyond that.
If only you had some clear idea of what you seek to convey when use the words" the universe", but you are about to demonstrate that you have no clear idea of what you mean by " the universe", probably because it is imaginary and no more than a vague generalisation. All universals are, and can only possibly be imaginary(vague unfocused generalised ideas/associations/images in the associative apparatus/function, or mind), In essence it is a portmanteau term and you have no idea what is in the portmanteau, or in plain teems you simply *cannot define " the universe" save in terms of vague generalisations
Yet you have no idea what you mean by " the universe" and cannot even begin to define it without resort to cognates synonyms, descriptions ans circularity
if anybody wants to know what dogma looks like you can find a pretty clear image of it at 11:11 always fun to see modern physicalists contortion to refuse the logical idea that there exists only one consciousness in the universe, which would explain everything, but sounds too "mystical" for their dogma
So the quantum eraser experiment makes me wonder if instead rewriting the future, there's simply a resonant harmonic in the time axis. We can't experience time as though it were a spacial dimension but that doesn't mean light can't also, especially since it experiences time all at once
It reminds me of a while ago when I saw an article saying that the ancient Greeks didn't see the color blue, as blue things were described as dark wine or something, and the researcher looked up ancient scriptures and found that other civilizations didn't either. they didn't had a word to define the color blue and so they could not distinguish it almost as if they were color blind, this would show that the language used would have a direct connection with the ability we have to perceive the world around us
This is a bit of a misconception. Colour categories vary from language to language and one language's colour terms might not necessarily line up nicely with another language's. The English word "blue" refers to certain wavelengths of light and excludes others, ancient Greek (and many other languages, extant and extinct) categorize what we think of as "blue" differently. Russian, for instance, has completely separate words for light and dark blue in the same way that we have ones for red and yellow. Vietnamese has a single term for both of what we would call blue and green. This doesn't mean that Vietnamese speakers can't tell the difference between what English speakers call blue and green, nor does it mean that Russian speakers can see "more" colours than English or Vietnamese speakers can. We all have roughly the same photo receptors in our eyes, we just semantically categorize them differently.
Here's an idea: The past and the future(s) are the same thing. Imagine an arrow with the potential to point in all directions in time, different futures and pasts. Almost all directions lead to an higher entropy. There's only some that have lower entropy. Now optimize for the direction of the lowest entropy. Do a step in the direction of that arrow and repeat that process. It lines out the path to a state where the entropy is 0. There is only one shortest path. But there are many where the entropy gets higher. Now the idea. I state that all possible paths exist. The question is why the universe's entropy was so low at the beginning of time. But was it actually? When you are thinking of the past you are just imagining an optimal path of many possible paths through time where the entropy is lower, and call that 'the past'. You can imagine any different path where entropy gets higher. All are equally real, so the one leading to entropy 0 as well. Why was entropy so low in the past? Because we define it to be so.
So you are saying that we observers experience the universe along the least-entropy path. But I’m not sure how this path is defined when performing a quantum choice experiment where a hit on detector 1 or detector 0 is random and not defined by whichever event is of lowest entropy… In short, can we prove that our path is the least entropy one ?
@@francoislecomte4340 The path to the lower entropy is what we define as _backward_ in time. When the outcome of the quantum experiment happened and is known, the entropy has increased because it could have been a different outcome as well. But there's just one path to lower entropy, which leads to the state what we call 'before' the measurement, where the entropy was lower.
Question: Is space actually falling into a black hole like consumption, or is it just a geometry? I ask because if it's consuming space, then a possible universe inside a black hole could be observing that inflow of space as an expansion of space after the formation of the initial big bang singularity.
Yeah that's one of the ongoing theories about how our big bang is basically just a white hole. Also talks about a repeating big bang. Can't remember the exact name for this. Think there is a Space Time video or even a series for this exact topic.
It's not swallowing space, it is curving space time. The black hole isn't actually bigger on the inside, it's more like a funnel that makes everything past the horizon slide towards the singularity which would be the 'bottom' of the funnel. That would be a moment in the future, so basically it locks all spacetime paths (the geodesics) that go past the horizon so they all lead to the same point in the infinite future, which is why you can't escape. As more and more energy is introduced into the black hole, the funnel starts getting curved even more aggressively and the horizon, where the funnel starts, expands outwards, that is how the hole grows. But there is no additional spacetime on the inside than the outside of the horizon no matter where it is, the only quantity that is changing is the curvature which dictates which paths objects can take. So the answer to your question is that it is just geometry.
@@zovisapphire Yeah I've been trying to parse how inflation could fit into it. The initial formation of a black hole shouldn't briefly stop and then restart under the event horizon, it's supposed to be a single event from our external viewpoint. The only way I could make it work in my head would be the extremely brief period between the formation of the singularity and the gravity beginning to pull in the surrounding space, as gravity propagates at C, not instantly. If there is a universe in the singularity then from it's internal perspective there would be a tiny delay from the formation of the universe until the external space begins cascading in. Perhaps that would give enough time for a CMB to form.
@@ThatCrazyKid0007 Where does the space in, and between the atoms go when it's all crushed down? Would be like wringing out a sponge. There would be extra space that was previously inaccessible, unless the fabric of space itself is also crushable?
@@NeonVisual It doesn't go anywhere, the space between atoms isn't getting smaller because the space is being 'crushed', it is because the curvature is so extreme it is forcing atoms to be closer and closer to each other. At one point the gravitational force is so insane due to the curvature that it is stronger than any quantum force like electromagnetism or the strong nuclear force and it crushes the atoms together so they take up the same position in space breaking Pauli's exclusion principle.
Episode idea: Could you elaborate on how Wheeler's "it from bit" fits in with the Bell-Kochen-Specker theorem, specifically thinking about work from John Conway and Kochen about a no-go theorem where there are sequences of observables that are mathematically impossible. If true, this seems like it might support Wheeler's interpretation. Is this even testable? Or is this something that quantum physicists don't put much weight in? I'd *love* to hear spacetime's take on this.
One of the challenges to the negative 20-Questions approach is that you cannot ask (or answer) questions in such a way as to arrive at a null hypothesis or it fails. The universe cannot answer these questions randomly, or you quickly run into paradoxical answer sets, such as an object being defined as both bigger AND smaller than a breadbox, nor is it possible to ask questions in such a way as to force a null outcome. Given that most outcomes are in fact mathematically or logically impossible from a given query state, these are actually pretty hard restrictions to satisfy, leading to rather strict behavior from most systems.
The crucial definition of Observation, that everything else hangs on, only gets an off-hand remark at 12:08 but even this is more than what most other content on the topic provides.
It's settled then. The tree falling in the woods does not make a sounds if no one is around to hear it. It is simultaneously fallen and not fallen until it is observed.
I may be wrong, any scientists reading this please feel free to correct me but ive always thought that the sound is irrelevant. When the tree falls it leads to the sudden motion of molecules all colliding with each other. You need at the very least (as far as we know) a human brain to gather the data from these collisions via small hairs in the cochlear of the ear and transform them into a signal that we can observe as sound.
it depends on your definition, a molecule bouncing into another molecule counts as an observation in quantum mechanics, so in that definition it still made a sound
There's another assumption in these questions that isn't acknowledged: that we can observe reality. Just as our eyes are only sensitive in a narrow range of the EM spectrum, our technology limits what we can observe. Our math says that particles exist as wave functions smeared across the entire universe. We acknowledge we have no way to observe that, but persist in acting as if it isn't true. What I've never heard is an explanation of how these wave functions interact in complex systems to create objects like people and eyeballs which appear as classical particles.
there have been a few episodes on quantum decoherence and this concept we're trying to understand: "when/where quantum becomes classical". As you can imagine, there's no perfect answer yet
Quantum-Mysticism was epicly covered by ‚Professor Dave’, a great supplement to this video here, which will in turn then hopefully lead you to his videos about the Discovery Institute, which then may direct you to the TH-camr Telltale, who covers what you have just realized through this journey-through-youtube: Quantum-Woo and Science-Denial ccan be very deliberatete. I’m sorry my Try to spread Fun/Science sounds so much like ‚giving Homework’, haha.
Wow, the participatory universe makes so much sense to me. This actually leads me to a very interesting idea: What if all possible universes do exist, but this universe is just the one in which I, (my conscious mind) exists? What if the only objective reality is a superposition of all possible states of the universe that could exist? In some versions of the many worlds hypothesis, the wave function collapses from the point of view of an observer, when the observer becomes entangled with the particle that is observed. The only observer that I know for sure to exist is myself ("I think, therefore I am"). So what if the superposition collapses from my point of view into the universe that eventually produced me. And everything I interact with collapses from the superposition and creates my reality. This seems like some egoistical, solipsistic point of view, but it also could mean that all possible minds do exist in their own universe, where the superposition collapsed to create them. This whole idea is sort of an anthropic principle, but instead of arguing based on the fact that humans exist, I argue based on the fact that I exist.
There is no waveform collapse in many worlds, hence "many worlds". All minds existing in their own universe is most definitely solipsism, but that doesn't necessarily make it wrong either, but it does imply that this comment is produced by an unconscious entity. Wait a minute...YOU'RE NOT REAL!! (Queue Twilight Zone theme) 🤪
Don't be so self-centered 😀 hahaha. More seriously, the Transactional Interpretation of QM is what we are looking at here which is kind of a version of this participatory universe. The observer is not some "mind" but simply the only possible state that can exist.. and this has nothing to do with conciseness -- itself a neural net + specific input/output side-effect. Let's just say, if your interactions with the world around you were a little different, you would not be asking the questions you are asking. "Apple does not fall far from the tree" is probably more applicable here. I'm quite certain that a fly also "I think, therefore I am", but since we don't hear it or can communicate with it and thus make assumptions; it seems it does not have the same impact, right? To put this another way, participatory universe means that universe does not exist until you interact with it. By "you" I don't mean *you*, but anything (proton, rock, etc). So yes, the Big Bang exists because we measure it. But we measure it because we exist and are a product of the Big Bang. Infinite logic recursion? 🙂Sounds like QM! 🙂 Now time to shut up and calculate!
you are basically describing the “many worlds” theory of quantum physics by sean carroll. he has some really good content on youtube, highly recommend checking his channel out.
@@Andynonymous_music no, here he's claiming that the entire universe from start to finish is in a superposition and the entirety of it collapses all at once into the one universe in which he exists making that observation etc. the moment he makes an observation
The Universe being created by its observers in essence means the Universe exists because its parts are interacting with each other. But I think it's the other way around. Observers exist because parts of the universe interact. I have no problems imagining universe without interactions, it would just be kinda dull. But there would be nobody in it to claim it's created by observation.
I personally think the "answer" is somehow linked to the idea of emergence. That simple things combine to make more complicated. Ant vs Ant Colony, Quarks vs Molecules. This idea extrapolated "up" to the cosmic level seems like an obvious step to take... how to take this step is of course, more difficult.
Is not a more rational and better way of formulating the question as follows:*can*(whatever is meant by) "the universe" "create itself"? Is it *possible* for the universe to create itself and what does the universe create itself exactly mean? Turns out that nobody has any idea at all either what can the universe create itself means or what "the universe" means or what they mean by the universe. You creatures use words without ever pausing to wonder exactly what they seek convey to you when you use them. No wonder you get so confused because you dream without clarifying your dreams or recognising that they are no more than dreams. They speak about "the universe" and when you ask them exactly what they seek to convey when they use the words "the universe" they can never ever tell you and the only possible explanation for that is that they have absolutely no idea what they mean by or seek to convey when they use the words "the universe". If you ask them what they mean by the universe they go in for psychological algebra or x=y=x, where both X and Y either have no value or are not defined or specified- They define one unknown in terms of other unknowns.
m>c9(+/-)~44÷9-/4[(-/+4)(8³-m²)]=cm>8÷T Good luck with this one. Hope it helps. 😎❤️ Only a short derivation. The "end" equation is just a work of beauty. Mind you this is slightly simplified, but it's an important part to understand the rest of the function. I'll come back later with more pieces.
I have some questions or ideas for an episode: Time apparently relatively stops at the event horizon of a black hole. So time outside of the event horizon has to move relatitvely infinitely fast. But Black holes are evaporating. So it must be impossible to reach this point where time 'stops'. Therefore, just before reaching the event horizon, there must be some kind of a firewall that converts all infalling stuff into Hawking radiation, and there can't be an inside of a black hole. What do you think bout this? Also, an event horizon can form from within a collapsing core of a star. Doen't that mean that this core is exposed again when the event horizon has shrunk enough due to evaporation, the core of the star is exposed again as a neutron/quark star? And one last one: Does there exist a maximun temperature? As the wavelenght of the radiation reaches the plank level, it can't get any shorter right? And does that mean that blak holes that have evaporated to one planck lenght in diameter can never evaporate any further?
Interesting questions As for the last one (does there exist a maximum temperature), I recommend you watch the vSauce video "How hot can it get?" TL;DW at a certain point of heat, it simply collapses in to a black hole
Time doesn't stop at the horizon, that is a common misunderstanding. The relativistic effect for an outside observer is that time _appears_ to stop for an infalling observer when viewed from the outside because none of the photons can ever reach us again past that point, so there is a causal disconnection at the point the horizon is crossed. However, for the infalling observer literally nothing changes when they pass the horizon, they wouldn't even notice (well, other than the insanely strong tidal forces that spaghettify you), but any information they could emit back to outside observers is trapped with the infalling observer as well because the spacetime is curved in such a way that nothing on the inside can leave past the horizon.
The problem is that there's too much wrong there. "Time" is not a thing that can stop, anywhere, and it is only the Schwarzschild global time coordinate that goes to infinity at the horizon, but this is unphysical. You can always switch to gullstrand-painleve coordinates where everything crosses the horizon just fine. It is a requirement of GR (see Geodesic Incompleteness theorems) that everything inside a black hole vanishes at the singularity, so they're vacuum spacetimes (they're empty), so no core that exists when the BH evaporates. Temperature can increase until the energy density is sufficient to form a black hole.
Here's an idea to look into: assume a base unit of spacetime -- say a "stixel" one planck-length in diameter and a unit of planck-time in duration -- but this has equal measurement in every part of the universe at a specific instant, whether matter/energy is present or not; also, while acknowledging that the ratio of this unit and the size of the universe would be infinite, assume that for any two points in time (X & Y), there is a finite ratio between the stixel at X & the stixel at Y. Finally, assuming all the other physical laws function in the usual way, just replacing spatial units AND temporal units with the the corresponding parts of the stixel, what's the difference between how an expanding universe looks and how a universe of constant size but shrinking stixel would look? Or, perhaps more interestingly, between a universe expanding where there is no matter/energy, or one where the stixel shrinks where matter/energy exists?
An episode on the question of "why is there anything at all" / "why is there something rather than nothing" and whether physics has the epistemic tools to answer it would be a great one, if you're looking for more ideas for episodes like this. Sean Carroll has some ideas on it
Ive had this hypothesis floating around my head for a bit, and I wanted to get some input on it. This hypothesis is closely related to the Big Bounce hypothesis, but it varies in some aspects. Hypothesis: When the universe becomes completely uniform time will "reverse", eventually turning our universe into one with white holes, is dominated by antimatter, and is crunching in on itself. This could explain why we dont see white holes or much antimatter at all in our universe without having to resort to extremely complex equations that have yet to precisely model our universe. As scientists have already hashed out, reversing time doesnt make a difference in terms of physics. Reversing time doesnt break our equations, our equations actually work exactly the same if time is reversed. The only thing it does is change matter to antimatter and black holes into white holes. So whats stopping a fragile, uniform universe from not being uniform anymore? Whats stopping time from reversing when entropy has nowhere else to go? And when time is reversed and the universe eventually crunches in on itself, whats stopping the extreme environment of the subatomic universe from rebounding and time going forward again? This hypothesis differs from the big bounce hypothesis by introducing the concept that time can reverse when entropy ceases. Its not just "our universe will expand to a certain point then crunch back in on itself". This hypothesis argues that the universe will crunch back in on itself by time reversing when entropy can no longer make things any more uniform. Whats more interesting is that the previously reversing universe that turned into our big bang could have left an imprint on the CMB. Something that multiverse theory proponents say could only happen from a universe outside of our own. Well, now they have competition if we ever do find an imprint on the CMB.
@ Chris Johnson: excellent hypothesis. Entropy seems to have no choice but to reverse after reaching maximum. Also, the imprint could be the matter/antimatter “anomaly and the neutrino imbalance (only “left handed “ with a 1/10 billion chance of one being right handed [the same ratio as the matter issue]). This would imply that our universe is is far down the road in “cycles “ , maybe number 10 billion 👀
Chris Johnson : I didn’t think about the entropy idea until you mentioned it. That’s very intriguing and could end up being more than just a thought...seriously.
In my view, the Copenhagen interpretation is realist to the extreme - perhaps even *more* so than the classical view. In the end, what it's saying is that an observation is a physical action, and the observer is part of the Universe and subject to the same laws as the system they try to observe. That was true already in classical physics; the new element introduced by quantum theory is that there is a limit to how *little* we can disturb an observed system and, what's more, the impossibility of measuring the effect of our action and retroactively taking it into account (in other words, we cannot even in theory reconstruct the state of the measured system *before* the measurement - we can only know what its state is *after* the measurement, which is what makes the measurement worthy of the name, btw).
I was thinking about what would happen in the negative 20 questions game if the questions ruled out all possibilities. I suppose that would be equivalent to destructive interference.
@@nachoijp but the negative 20 questions happens backwards, you're using the rules of normal 20 questions. If the yes and no answers to the questions always alternate and the questions are: 1) "Does it exist?" - Yes 2) "Does is exist?" - No Does that cause a paradox? Or does the second answer override the first to prevent a paradox?
@@CircuitrinosOfficial tIf I understood right, the alternate answers was just an example, not a necessary rule. Maybe if you string a series of questions that end up in no possibility, then there's only one last significant question to ask (does is exist?) , and the answer would be no, because then previous answers made it impossible to get anything different
I think the discussion at around 13:10 really puts this in a good perspective. Quantum-level particles might exist in a state of superposition until we observe them, but they do still *exist* before we observe them. The particle doesn't pop into reality when observed; it just commits to one type of reality. So the realist position still holds up on a macro level. The "substrate," as he called it, exists whether or not we observe it. It just gets more specific when we do.
Maybe Spinoza was right: reality is a self-expressing self-signalling system! Thank you, John Archibald Wheeler! i wonder if Einstein and his obsession with Spinoza's metaphysics would welcome this information-theoretic version of Spinozian metaphysics?
Could it be that “observation” is a just a further entanglement that then binds your larger system to a smaller system thus “collapsing” the wave form? Sorry if that’s not very coherent.
Could the collapse even be a form of singularity in itself? If information has mass a la dark matter, wouldn't a critical mass in this case be just like a mass of any other kind?
@@w4ffu1z I would guess that information can't have mass, due to the fact that it can be carried by massless particles (i.e. photons). Though I've heard weirder things in quantum mechanics, so I wouldn't write it off just off logic alone.
This idea makes perfect sense to me. It seems like the same type of situation as general relativity. Without two different frames of reference interacting with each other, there can't be many judgements about what the "facts" of a given situation are. Am I stationary or moving at a constant velocity? Etc. Its all a little fuzzy and basically kind of meaningless unless there's another situation you can use for comparison. "Relative to what" is where the real action is. The fact that you can compare the two is what allows you to establish facts about either situation. The "observer" thing is often misinterpreted, but I do think that its very reasonable to suggest that reality is relational, not objective. The facts about the world are established as a consquence of interactions between things, not by the things themselves. You might even say that there's no such things as "things themselves", its just relationships between things all the way down.
The Beginning of the Universe is like the End-- Irrational. This means it can be caused by reason, but will immediately assume it wasn't. There can be many, many irrational points and they will define other spaces more easily than be defined themselves. Therefore, the Universe can have a beginning, and an end, and they are defined, yet are more likely "form" and not hard edges. Fun! I enjoy your videos, PBS.
The only problem with the delayed eraser experiment is that you have no choice in the matter of putting the second splitter or not. So the photon "knows" exactly whether it will be there or not because the universe already decided it through it's infinite amount of initial conditions. Furthermore, from the point of view of the photon it all happens at the same time so there is no inconsistency. The trouble comes from the assumption that we are isolated from the wave function of... spacetime.
very low probability . it is just the same as saying the universe is spinning around the earth and the earth is not spinning . "wave function of... spacetime." not sure what you mean. two crucial information is needed to understand the delayed choice experiment , the detectors are polarization filters , they polarize light , but while doing so reduces or completely block the light . to have an interference pattern two separate beams of light must interact . you can look at the experiment again , and it becomes clear what is really happening .
Problem with superdeterminism is that it is not compatible with truly random probabilities (as you could use radioactive decay or the like to randomly, with no known variables to encode decision information, make the choice) which is hard to reconcile with the bell inequality in scientific way (de broglie pilot wave theory does not realy get to count in my book as it is not compatible with QFT so is not really a full interpretation of qm, plus non-locality is very gross)
@@m.c.4674 You can just put your reference system in sync with the spinning Earth, which is what you do when you look at the stars lol. The wave function of space-time is the universe, I'm arguing that you cannot truly isolate two parts of it. You don't need two "separate beams". My grasp in QM is weak but I believe all particle path calculations are done by calculating all the possible paths and seeing how they interfere. So in a way a photon can interfere with itself.
All interpretations of quantum mechanics results from the double slit experiment. I always go back to the basic experiment in my head. I always have a lot of new questions to ask after running trough the tought experiment. After I try to answer these, I usually end up with a new interpretation. But first two important issue needs to be clarified for me: 1) Does every event horizon have some kind of horizon radiation (virtual particles)? 2) When we examine a single photon's light cone, what happens at the border? I have a lot a follow-up questions...
The event horizon question is quite interesting actually! As we have an event horizon at the edge of our local bubble caused by the rate of expansion of spacetime, almost the inverse of the event horizon at the edge of a black hole, however off the top of my head it would seem that some of the rudimentary explanations for hawking radiation would still work for that horizon. As hawking radiation steals it's energy from the local curvature of spacetime around the black hole (thus decreasing it's mass) I suppose in this case the energy would be taken from the local expansion of space time (thus decreasing dark energy). Very interesting, however it would take some rigorous maths and physics to actually say whether this happens.
double slit and quantum erasure are my favorite two experiments because i believe they hold the key to our reality. And someday, I think Many Worlds will be proven.
@@DekarNL In a moving reference frame of a photon, future and past lightcones are also event horizons. What happens at those borders? Take Cherenkov radiation for example.
Imagine how the universe could look like to observers on such size scales where no baryonic matter is detectable - kind of when it could be explained as a "hypothetical energy soup" from perspective of observers of such large scale, that observing anything smaller than googleplex parsecs will be impossible to them.
Beautiful episode. Been following this channel for years and it made me understand things in ways i never thought possible and opened allot of thought processes i never even dreamed of. Thank you for these PBSspacetime.
Idea: the programmer of our simulated reality implemented quantum mechanics as a compression algorithm. In that way they didn’t have to define all variables unless used (observed). And we’re all scratching our heads…
i keep having the intuition that it's more like a game where they don't waste CPU time on regions that haven't been explored yet. maybe a hot gas only has macroscopic quantities like temperature until somebody needs to know the velocity of a molecule? or until it makes a difference like cleaving another molecule? and the speed of light limit feels suspiciously like someone is compartmentalizing the universe so they can process chunks of the game separately
Gives an initial observation, as well. One from which our observed reality had evolved from. So even though our observations are relevant, they're still an eventuality of that first observation. Or am I way off?
good try, but surely a lazy programmer would have done anything but implement quantum mechanics! As Shor Quantum Algorithm shows, a relatively small quantum computer have an intrinsic computing power superior to all the classical bits existing in the universe
@@ags5377 you can't just compare computing power between quantum and classical computers. Quantum computing can only give you more power for certain specific situations, it's not generally mode powerful.
The only problem I have with the universe only determining it's characteristics under observation is that it's all constantly being observed. If photons move at the speed of light and don't experience time, then from the perspective of photons they're all being observed all the time, right? So how can we claim to observe or not observe something? It must have already been observed.
The observer effect is probably the worst choice of words for what it's trying to convey. It almost makes it sound like the universe is sentient, and only takes shape when it notices someone looking at. The observer effect really has to do with the way light affects objects on a quantum level. We need to light to observe things, but the energy light carries can move or displace Quantum objects since they are so small. So the act of trying to observe quantum objects means displacing them with the energy that comes from light. So We can't ever really see what they were doing before we see them reacting to light passing through. However the observer effect doesn't do anything at all to things we can see. In the big world that we can see with our eyes and telescopes, light doesn't carry enough energy to move objects around. Things don't move around your room when you flip the switch on and light certainly doesn't carry enough energy to make planetary sized objects appear out of nothing because someone looked in that direction. The universe will still take shape with or without being observered.
@@JustinL614 Metaphysics must exist because physics is finite in its explanatory ability, as the human beings which conduct physics are also finite. What I'm saying is that metaphysics exists to provide potential answers for questions that cannot be solved by physics.
I am overwhelmed and understood only (generously)like 30% of this. That said I am also really glad someone is thinking about this and does understand it!
When I was a much younger person, I had a magic mushroom-fueled epiphany that if one was to come to understand the true nature of all 'creation' (remain calm, I'm using that word generically), everything would cease to exist. I still believe it, 40 years later.
Looking forward to future videos on this topic! It's interesting how some physicists have started to become more phenomenological (if that's the right word). I feel like we're on the cusp of some great convergence.
It worries me, I think they'll just find God and then the universe as we know it will implode because man ruins everything he touches. They'll unplug the computer this simulation is running in destroy the fabric of reality.
The universe answers every question with 'yes', except when that answer would be in contradiction with any of the previous answers. Therefore, the questions create the universe.
I love how you explain Schrodinger's Cat and how ridiculous it is - I tried explaining these points a few months ago to someone and they simply couldn't understand how the thought experiment doesn't work in real life. Funny how deepening our education helps us see the world in a different light.
![[MV] A leap of faith...ความเชื่อใจครั้งสุดท้าย (From "Petrichor the series")](http://i.ytimg.com/vi/U1piZH2CNXA/mqdefault.jpg)
imagine going to a 19th century physicist and telling them that 21st century physics is plagued by enormous nigh-unsolvable philosophical questions - but that we're also unsatisfied because our theories break down "only" before 10-³² seconds after the beginning of the universe
They'd say "the universe had a beginning???"
CCC for the win
@@starofcctv94 lol yeah and the fact we know that is entirely mundane to us. the big debate is actually what happened before the beginning. which we somehow have ideas about, with evidence, despite that definitely seeming impossible.
@@monkatraz
Correct me if I'm wrong but aren't we basically making assumptions based on certain observations (red shift etc) and mathematically working backwards to end up with the "beginning" or "big bang" scenario?
It's heavily possible given our current understanding that we've missed something crucial, especially given the limits of what parts of the universe we can actually (or will ever even be able to) see.
@@paulpesci1 We are, but our assumptions are very reasonable and the evidence that the universe used to be ludicrously smaller (aka the big bang) is overwhelming. It's hard to interpret what we see out there as anything else, even if we question our assumptions.
This actually sounds like how I often run games of dnd. The players enter somewhere, a place I have yet to fully design. Then, as the players ask questions "is this room well lit?", "how far away is the next door", "can I climb this wall?", it forces me to choose the nature of the location. Only because the players asked did the room become how it is now!
With that analogy, I now imagine the universe being asked by scientists "how does this work?" and the universe stuttering as it poorly explains a property, as the scientists fervently write notes.
This is how I design D&D puzzles. I just come up with the puzzles, I never design a solution. I let my players do that. If it sounds at all feasible, it works.
As they say we are created in god’s image
this is awesome! thanks for sharing the insight. But I don't get how the scientists' fervently writing notes corresponds to the choosing of a location. Could you explain?
Reality is just DnD with extra steps xD
@@ayoubzahiri1918 God looks like an idiot then since I'm made in his image
This reads like a scientist living his own Lovecraftian horror story. Knowledge so unknowable that one begins to go insane from a sudden intuitive understanding that they can't put into words because the words don't exist. But the fright and despair in the eyes of the afflicted is so intense that you can only shudder at the thought of such a horrifying realization
Probably an electricity bill.
Can every thought be translated into a combination of words? Are there thoughts that you can't communicate to others because language is limited?
You ever experience an emotion you couldn’t quite pin down with words? I definitely think there is a limit on what we’re able to communicate with each other verbally; it’s why languages have so many words-to feel infinite when they really aren’t
whats horrifying about it? its literally so based and cool. stop living in fear, try metta meditation
@@bitterlemonboy you hit the nail on the head. I think something we ALL experience to some degree is having a very complex, detailed, or involved thought... And you just can't say it in a way that will communicate the concept fully.
It can be a terrible feeling, but if you learn to temper it, you can find that sweet balance between what you say and what you don't.
Believe it or not, it's not about what you say but rather what you TRY to say. Every effort works you towards a direction, with various effects as a result. So I may verbally say one thing, but whatever I was REALLY trying to say will effect how I automatically think in the future. It's complicated, of course, no concept can be full said, but different levels of general overview can be given, and each level can help better the understanding of those who understand it.
The mass of the entire universe in a black hole producing the size equal to our cosmological event horizon was such a cliffhanger. Please elaborate on this next time.
The aspects of this sort of quantum observer effect that most interest me are when the interactions occur over vast distances. Ten billion years ago, some galaxy near the edge of our own observable universe emitted a photon into deep space. This photon didn't just go in one direction, but according to QM 'rippled' outwards like a wave, potentially interacting with countless octillions of other particles along the way. The ripple expanded outwards in many directions, through nebulae, planets, other stars, probably other telescopes belonging to aliens *outside our observable universe* and by chance it didn't interact with any of them, passing over all of them without a blip - until one day that wave - now 20-billion light-years wide - suddenly resolved as a discrete ping on the CCD of the Hubble Telescope. The photon who's position was indeterminate for over 10-billion years, possibly anywhere within our observable universe or well outside it, suddenly was THERE for just a moment, and likewise there may have been an instantaneous entangled quantum interaction with the electron responsible for emitting that photon so long ago - even though the galaxy from which it came is probably now far beyond our particle horizon.
Equally interesting, as photons move at the speed of light and thus do not experience time, that interaction was - from its standpoint, if it could be said to have one - instantaneous.
I love how you put it. This is mind-blowing. I actually had the idea of quantum observer in mind as the video rolled in, before that interpretation was suggested, and I was thinking every interaction defines reality, but then how could it be true in light of the delay induced by the half-reflecting mirror experiment. Well I don't think what you said fixes that problem but it's still interesting to think about
@@trifonTAF Yeah. I'm still trying to wrap my head around the particulars of that experiment and how it describes interactions. Don't feel like I have a good grasp of it yet.
Makes you wonder how much of a 'flow' of photons/waves there is from a star. Are there staccato gaps or are these photon/waves a constant unbroken output.
as you state yourself: the answer lies in there being no time from the photon's point of view. Hence its apparent feedback of time-reversed choice while interacting with its environment. Not only is space and time relative and undividable from each other, so are the 'act' of measurement and its apparent influence. The cause and effect relationship only makes sense when there is no actual time, because if time needs to be reversed for it to make sense over long distances, one should seriously start to doubt how crippled our experience of time actually is.
freaky when you put it that way, simple when in Jargon.
PHEW! Since the universe creates itself, it won’t leave me for some other universe on Tinder!
😆 🤣
Great joke.
Tinder seems to be mostly bots in my area.
Tay! Hope you're OK! Been a while!
CHOCOLATE TAY
When I started watching this channel I thought a career in fusion was a pipe dream. Now I've worked on a research device and will be working on SPARC.
Plasma physics is a deep field but it's very interesting. Please do videos on it!
Sounds cool! Make sure to fill out the survey.
I believe from what I have seen so far from may science movies that many things are emergent like Time and gravity.
Congrats...Im pleased your dream turned into reality..
Im so jealous im way to stupid for that
Our BIG BANG is just one of trillions of other BIG BANGS at unimaginable distances. (Actually Infinite big bangs is a truer fact). SPACE HAS NO END AND TIME NEVER ENDS (Both also had no beginning) Once your brain finds this to be a TRUE statement your half way to understanding the theory of EVERYTHING.
In the mean time I want this guy to go inside my coffin while I shoot it with a machine gun. He likes the "cat in the box theory" so he should put his money where my lead is.
Dark energy is a near infinite mass of ice cold neutrons that exists in between galaxies and our big bang is surrounded by billions of other DEAD Big Bangs now COLD and with only neutrons that gather to form the next big bang at a critical mass where MASS is converted into pure ENERGY AGAIN and again and again and never in the same place twice. A big bang life cycle is about 500 to 900 trillion years depending on the materials surrounding the DARK SINGULARITY (a Black hole with the mass of a big bang.) This makes all big bangs about the same size since the critical mass is always the same to create 9th Dimensional matter or a Neutron Crystal devoid of all heat (Zero energy with unimaginable mass) There is your strange "Dark Matter" simple neutrons and lots of them. Lots of mass but no light, no energy, pure dead matter with no Pauli-exclusion principle at work, no heat or voids = NO ELECTRONS between the NEUTRONS at all!
\psi = probability amplitude that electron 1 is in state a and electron 2 is in state b
\psi_{1}(a) = probability amplitude that electron 1 is in state a
\psi_{2}(b) = probability amplitude that electron 2 is in state b
Dark matter /psi state is ZERO electrons and only pure cold neutrons.
The thing about the 2 entangled particles which somehow communicate at a distance, even a distance of light-years, gives a good clue to the underlying nature of everything. The laws of symmetry: rotational, displacement in space and time etc all connected to conservation laws like conservation of angular momentum and momentum etc. Now the measured particle with spin “up” “causing” a distant entangled particle to have spin “down” happens because the law of conservation must be obeyed, even if things are light-years apart. So, it also tells us that the information about the up and down spins is more fundamental than distance. Therefore, we have evidence of an underlying informational universe more fundamental than our apparent physical universe. That much is clear.
Well-deducted!
For what i'have come to know, the entanglement effect stipulate only an _associative relation_ between two particle at distance, so it would be that the particle [x] is _related_ to the particle [y]: it would be impossibile for a "comunication" to happen because it would violate the generally accepted principle of special relativity (light- velocity is the max velocity in the universe).
For a comunication between particles to take place, the information exchanged would have to travel faster than light, and since it is know to be not possible there has been proposed the "non-comunication theorem" that conserve both this qm phenomena and the coherence in the relativity framework.
No one considers how many of the particles on earth are already entangled, by their very nature of coexistence on the same 'material plane'
Which means we are all already entangled with each other at the quantum level. What's more DNA itself is normally in a Ball shape, and works as an antenna
Then there's the Schumann Resonance, and Morphic Waves... and the temporally retroactive influence of Quantum Wave collapse at point of observation.
What's more that would mean we are already a single Superorganism, working like a Galactic Brain in a State of Self Consciousness Observation of itself
A Singular Plurality
Being a big fan of both science and philosophy, these episodes make me so happy. I wish I could have learned more about this in high school. Then the intrinsic uncertainty of the Universe wouldn’t have felt so problematic, but rather the natural state of things.
Philosophy is useless. It's never produced a thing. Try demonstrable reality.
My human knowledge couldn't really understand the universe, but I trust Jesus know all about it. So I must follow him.
@@simonsong1743 lol
Sadly this type of stuff is not being teached in school. It would've made so many more interested in science instead of loathing it.
@@bronchialaktivbalsam3830 Well, status, money and a nice work environment are drivers that steers the most qualified people. We could actively work to push a bigger slice of the pie towards teachers and the system that backs them up. It requires the very brightest to explain complicated stuff at the right level.
Thank you Mark Evans for supporting the channel!! Im a young entry level engineer not making much but I feel obligated to donate and support after watching this channel for so long. Never stop PBS Space Time !
nah bro you dont need to, although its very kind of you.
and i agree, this guy has an awesome channel
I'm a high school dropout and I love this channel
I think there is plenty of space in the field of physics for philosophers. Science currently only measures the physical aspect of the universe but there is clearly something more that we are missing and I think having philosopher physicists working on finding new ways to think of these problems is extremely helpful for the field as a whole to grow. We may not be able to measure consciousness now but maybe it will be these philosopher physicists who find some way to do so in the future!
Amanda Gefters book “Tresspassing in Einstein’s Lawn” covers this whole topic, and Wheeler’s contributions to it in a lot of depth. It’s an amazing and lovely book.
Hi Matt, long time viewer, and thank you for presenting Wheeler's interpretation. I am not a physicist, but for years I always thought of the delayed choice experiment as follows: since light does not experience time, there is no such thing as "delayed choice" for the photons. From their perspective, the different configurations of the experiment simply eliminate possibilities, and the photons end up in a superposition of the remaining possibilities that are consistent with the configurations.
Sorry if my interpretation is overly naive. That's why I will keep watching your show. Thank you, and please keep them coming.
This is exactly what I thought as well. And it is great that it can eliminate the 'need' for the fine tuning of the universe...
the -20 questions game is also used in the book "consciousness explained" to describe at first, iirc, how dreams arise, and extended later to be a more general theory of how conscious experience in general arises. interesting, the parallel thinking about two seemingly very different subjects.
That's because they're exactly the same subject.
I dont believe that consciousness is required for reality. That would mean theres nothing beyond the observable universe, because we can never interact with it and never will be able to interact with it. And we're pretty sure thats not true. Theres likely stuff outside the observable universe.
Also, we know of a time before life on Earth. It had to exist, because we're here, but nothing was conscious.
that would explain why dreams always seem to start in the middle
I believe from what I have seen so far from may science movies that many things are emergent like Time and gravity.
Reality and consciousness could be like SpaceTime in which as Einstein put it they are different aspects of the same thing
Meaning there is a connection between but we aren't aware of how the connection works or even what type of connection it is
As I watch more and more videos about quantum mechanics, I am further convinced of the idea that the wave function is the universe's way of implementing lazy loading for optimization.
For clarity, lazy loading is the programming principle where resources or objects are not initialized until they are actually utilized.
But does it not take more work to calculate both probabilities especially when both possibilities interfere with each other like in the double slit experiment? Does not seem very efficient or lazy to me.
@@H4XO5 Depends whether the bottleneck is in calculating the information or loading it.
Since transmitting classical states requires production and interaction of photons, thermodynamics might make it preferable for the universe to have 'zero-particle' information transmission via waveform collapse, if you want to subscribe to Copenhagen, or state-checksum pass, if you want to subscribe to Everett. Not sure where Bohmian mecanics would fall in this example.
That doesn't really make sense. Imagine two particles that are in their own respective superpositions suddenly interacting. Lazy loading implies loading resources on demand, in this case the state of the particle, but how would the universe/particle know *when* to load this resource (in this case, the state to which the superposition collapses to) if neither particle is doing any calculation before the interaction?
If the universe doesn't care in which state either particle is before interaction and they are in that undefined superposition to save computing resources on the state of the particles, then how would it know when to actually start computing their definitive states when the demand is created by the interaction, how do you keep track that such an event is fired? And how would the algorithm decide on a definitive set of states in the interaction if both of its inputs are undefined? You're still doing additional computation in the background to keep track when this occurs and you need actual data as input to make a decision, so there is no real optimization in anything.
The idea seemingly makes sense because you're only thinking of one side of the interaction, but both particles participate in the interaction, it'd be like having two sleeping threads suddenly waking each other up by themselves which doesn't work, at least one has to be awake or you need a third one that keeps track when to wake both of them up to do the calculation. No real performance boost there either way.
It is appealing but consider, what would a program be without a computer. If you compare the universe to a computer code you are assuming that the universe exists inside some sort of closed state computer which runs it? I don't believe that to be so. It would be like saying because the universe contains light it is like a camera capturing light also.
In the days of Newton, when the marvels of Europe were clocks, scientists tended to think of the universe as a giant clock, with planets going round in regular orbits. In the information age, when computers are the preeminent technology, we have an urge to think of reality as digital or a simulation. How do we know we're not making the same mistake again?
One of the greatest videos I have ever seen. Similar feeling to when I first studied philosophy and Buddhism and learned that many of my own ideas had been explored and organised into theories by people long before me. This makes me feel a lot more comfortable in the absolute abyss of this questioning. Happy to be here and be a part of history - whether this is all an illusion or some big answers come our way soon ❤
I'd be interested in hearing your take on Penrose's idea that if the universe ends up decaying entirely into massless particles, then the notion of space collapses and you have a universe's worth of energy in a no-space, which would provide the initial conditions for a big bang. Sort of an oscillating universe theory, except without any collapse.
Conformal cyclic cosmology. You should buy Penrose's book. Great read :)
Yes! I’ve been waiting for a Spacetime episode about that..
They already did a video on Penrose's Conformal Cyclic Cosmology, dig through their channel a bit as I forgot the exact title of the video.
@@ThatCrazyKid0007 Yup, it's called "What Happens After the Universe Ends?", from about two years ago.
My money's on evaporation.
Perhaps a series on "Why QM and GR disagree" some lead up episodes getting down how the equations have problems mixing, progressing into how hypothetical GUT's get around or attempt to fix these issues and the subsequent issues with those theories and their predictions beyond whats needed? This may be a tad too math oriented as that's the main sticking points for the two otherwise it would be easy haha. But anything like that would definitely be helpful in getting a bigger picture of what cutting edge physics is dealing with. Cheers!
There are non-mathematical, conceptual ways to think about the problem. A big part of it comes down to time: Relativity establishes that time is a mutable dimension tied to space, whereas quantum mechanics treats time in the "classical" way of an immutable background on which processes can be measured. In short, under quantum mechanics, spacetime doesn't bend, which makes it unhelpful in understanding what happens at the particle level when spacetime is strongly bent according to relativity.
It’s less that they disagree, rather that one works on one scale, and the other works on another scale. The issue is we have no idea how, when, or why the transition occurs from micro to macro. The closest we have is coherent quantum wave function super positioning, and objective wave function collapse. Which leaves us with more questions than answers.
@@badlydrawnturtle8484 but can’t we do qft on curved space times? isn’t the problem just that we don’t have a good model of how the curvature follows from superposed matter?
@@kashu7691
It's more fundamental than that. Quantum models assume that time is separate from space; they're built upon fundamentally different assumptions from general relativity, which takes space and time to be a four-dimensional manifold. This is why the problem is so difficult; the underpinning notions of how space and time operate are incompatible. It's not as simple as finding some neat mathematical links to tie them together: One of them is necessarily, fundamentally, WRONG.
@@badlydrawnturtle8484 QM is fundamentally wrong. Super positions and waveforms don't exist, they are just a fudge for an unanswered question. The cat is not dead and alive, it's either decomposing or really pissed off.
Perform the experiment, and leave it running for 1 year, I bet that the answer will always return a dead cat, proving that the super position theory is a fantasy. We may not know the exact moment that the cat died, but that does not mean it was dependent on being observed or interacted with.
it's only Spacetime where I expect videos with "woah dude" titles to involve hardcore physics
The universe may or may not be creating itself, but what IS definitely happening is that the Universe is aware and trying to understand itself - by the sole fact that we humans are part of the universe. I just think that's amazing - that an entity that bursts forth from a amorphous plasma and evolves to learn about itself.
Babylonian mysticism/Kabbalism in the guise of science, nice try hermetic cultist
It is beautiful, also somewhat terrifying as I think about the book Annihilation and movie.
you mean something like this?
th-cam.com/video/h6fcK_fRYaI/w-d-xo.htmlsi=1_lGK7vHWFohj2XM
For all people It's important to remember this
Ah maybe! But through what mechanism?
I've agreed with the idea that "observation" is "interaction" for a while - I know NdGT has struggled to explain that to the public for some time. But the experiment described in this video raises a question - how does the reflection off a mirror/beamsplitter not count as an interaction that would collapse the wave function, but the measuring device does? Surely reflecting photons involves particle/particle interactions, so I don't understand how superposition survives that interaction. What's the real line in the sand here that constitutes a meaningful interaction?
Very well put. Exactly my thoughts
I struggle to make sense of the question of when a quantum measurement occurs without invoking decoherence. The wavefunction didn't collapse in the first beamsplitter because it didn't decohere with the external environment (unlike when it interacted with the measurement apparatus after the second splitter).
I believe the beam splitters are carefully manufactured so that they're very regular, and so can interact with the wave function in the desired way without completely scrambling it.
As for what counts as an interaction that would collapse the wave function? That depends on your interpretation of quantum mechanics.
According to the interpretation presented in this video, it would only collapse when observed. So if humans are observers and measuring devices aren't, then even interactions with the latter wouldn't collapse the wave function. However, Wheeler doesn't specify what counts as an observer, so it could be that measuring devices count and do indeed collapse the wave function.
The Copenhagen interpretation (the first and most commonly taught one) just says that the collapse happens at some point, but there's no generally agreed upon point. Presumably it would happen at some point between the moment the photon hits the receptor, and the moment conscious observers process the results.
Other interpretations argue there's no collapse at all though, like Pilot Wave Theory and Many-Worlds. In Many-Worlds (my favorite personally), the wave function instead gets scrambled as it starts encompassing more components of the measuring device and the surrounding environment, and so it stops meaningfully interfering with itself, whereas it could when only the beam splitter was included. This is the process known as decoherence. So in that interpretation, the observer doesn't collapse the wave function. They just become part of it, but can't interact with the other outcomes because the whole system is now too complex.
There's not a lot of practical ways to falsify any interpretation, so that's why it's hard to definitively say what happens. It's mostly a philosophical debate for now. Look up "measurement problem" if you want to know more :)
Good question
I think some "interactions" do not permit measurement, i.e. the beam splitter splits the beam, but has no method to know how the beam was split. So whichever outcome (path A vs path B) the beam splitter is completely identical, and no information on where the photon went is left with the beam splitter. If you somehow modified the beam splitter to measure it, then the wave function would "collapse" due to the disturbance. Though to be honest, I am not sure, since I would think even a single photon, with no change in it's energy (frequency), but it's altered direction would have a different momentum, which would be 'felt' by the mirror, and therefore observable.. though perhaps the change is so small it doesn't constrain the photon wave function enough to collapse it to a 'classical' measurement (the mirror just gets entangled into it's own superposition??). Ok I definitely don't understand QM lol
Also, for a real laser/beam splitter set up, some fraction of the photons would be absorbed by the beam splitter and slightly heat up the material, but in that case that is a measurement, and the result is the photon doesn't take either path A or B..
Thanks for your challenging and interesting dives into QM, GR, etc. I'm an astrophysicist by training and a systems engineer by occupation, and you have helped my understanding of a number of complex topics that I'd wondered about. Please keep up the good work.
as long as "observation" is defined as *physical interaction* i totally buy it.
yeah, this explanation makes MUCH more sense than the day-to-day definition of "observation"
the thing is that observation is fundamentally impossible without interaction. We see things because they reflect photons. So observation without interaction doesn't make sense in any context really
But not all interactions?.. In the delayed choice experiment photons are deflected by mirrors and it doesn't matter in the end. How is interaction in the detector different from interaction with mirrors?
Physicality in this context doesn't make any sense.
An electron has to be observed to collapse to cause electromagnetic forces to repel.
What do you mean by physical interaction exactly?
What does "physical" mean?
I mean this is probably the best TH-cam channel in our universe for people who love questions and want to imagine.
Thank you PBS for making me a better student and for sharing all your passion for physics with the world.
I honestly don't know if this message will ever be found by anyone in a universe of information that may or may not be partially created by our observation.
Again thanks for inspiring me.
P.S.
As I stare at the universe, the universe stares at me.
I don't know if this phrase means anything but I like how it sounds!
Yes it does, one day we will look up into the stars and say "why look that's me"
We are the big bang. All of everything came as a result, we are the evolution of the Universe itself. You are never alone because the universe is you.
Yea i always wonder what the world would be like if channels like this, pbs eons, moth light media, sci show, crash course, sci show space... etc... were popular as tiktok... what the world would be like.
As an anthropology student strongly engaging with ideas drawn from phenomenology I find this debate within physics the most exciting by far I have ever heard of.
If you rephrase the negative 20 questions as the "questions" being interference between different components of the universal quantum wave function, and the "answers" being positive interference, it seems to me that it basically has to be true that the "real universe" is just whatever is left when all of the other possibilities have been removed by destructive interference.
Mind blown...
This idea deserves a lot of attention.
There's interesting parallels to this idea to be found within the physics of consciousness. The electromagnetic theory of consciousness posits that the waves of electromagnetic coherence that arise from the underlying electrochemical action of a brain's billions of synchronized firing neurons "carve" the quasi-stable patterns experienced as conscious phenomena into the relentless, impossibly chaotic and complex storm of background electromagnetic field activity. But achieving a sufficiently high SNR might not just be an amplifying function but also involve a process of destructive decoherence across the relevant ranges of the electromagnetic field within the space occupied by a brain.
Given the brain's massive parallel processing architecture, such action would have the effect of serving as a naturally evolved form of error checking neurological information processing as incoherent information - likely indicating wrong/incorrect internal representations of the external world - would destructively interfere with each other, preventing both it from arising into conscious experience and providing a phenomenological feedback mechanism in the form of psychological discomfort we term cognitive dissonance.
"Where did I leave my keys...?"
*brain subconsciously evaluates numerous potential locations while recall functions attempt to recover the relevant memories such that potential locations not in coherence with what was partially recorded in memory interfere and are deamplified while the actual location constructively coheres with the low-fidelity memory recall function, amplifying that pattern sufficiently to generate a conscious experience of the keys being left at that location*
@@suchislife801 Sherlock was solving crime, not studying the universe lol. Both are plagued by human infallibility however. Can one possibly conceive of everything impossible in the first place?
@@suchislife801 It is a stance filled with an unstated
arrogant belief that one could know all the possible choices.
eliminating impossibilities is not done. one calculates at most the more or less probable.
the thing ive learned from myself, and other people, is that we often look for patterns, and in a desperate attempt to make sense of chaos, trick ourselves into seeing them for comfort.
This programme is keeping me awake, lol. I can't believe a better physicist to illustrate these concepts. This man is up there with Lenny Susskind. He doesn't care for the BS but does care physics is understood.
Which BS is that?
I think the cleanest view is that "collapse" is emergent from the web of entangled particles that make up the matter in the universe. Once there's enough particles whose wave functions are entangled, they constrain the wave functions of all the other entangled particles to the very narrow wave function that we associate with a classical piece of matter.
I believe from what I have seen so far from may science movies that many things are emergent like Time and gravity.
WTF?? How exactly does “collapse” emerge from entangled particles? Does your “collapse” also encompass non-matter particles, such as entangled photons? Why is there a distinction between the “collapse” of matter versus non-matter particles? Also, you do realise that collapse is a verb, not a noun, right? If so, how is it in any way possible for a verb to emerge from anything? This really doesn’t make any sense and seems rather illogical. And what is meant by “the” matter, is whatever you’re referring to somehow different from all other matter? If not, what’s the meaning of the word “the” preceding matter?
You then go on to say that “enough particles whose wave functions are entangled” but you have no explanation of what constitutes “enough”, so exactly how many entangled particles are indeed “enough”? How does any entangled particle “constrain the wave functions of all other entangled particles”? In what way/how are said wave functions constrained? What then happens once a wave function has been constrained, how is it different from the wave function prior to this constraint and why exactly is it being constrained?
Finally, what is this “very narrow wave function that we [please, speak for yourself, I most certainly am not to be included in your “we”] associate with a classical piece of matter”? Since when does anything “classical” have anything whatsoever to do with quantum processes? I’ve never heard of “very narrow wave function” which someone could “associate with a classical piece of matter”, how is said wave function derived? And what exactly is meant by “a classical piece of matter”? How small/large is your “classical piece of matter” and what’s meant by “piece of”? Matter isn’t usually considered as something which one can take a piece of, it’s more a generalisation for myriad elementary particles, atoms, nucleons, etc. So, to take a “piece of matter” isn’t something one would normally speak about. Even if you had simply said “classical matter” or better yet, just “matter”, this might be slightly easier to understand, but we’re splitting hairs here, I think.
I am truly perplexed by your comment. It would be great to get some (actually, a lot of😊) clarification as to just what it is your cleanest view entails and how anything close to the usual meaning of the word collapse, in a quantum sense, could possibly be emergent from entangled objects, irrespective of whether they constitute matter or otherwise. And the processes by which the emergence occurs, what defines the number of “enough particles” (and who decides when enough is enough?)? So these particles which are entangled and are subsequently constraining “the wave functions of all other entangled particles”, are they constraining the wave functions of all other entangled particles in the entire universe, the visible universe, just the single particle with which another has been entangled or what, exactly? Last but not least, how wide or narrow are wave functions in general, regardless of whether said function is (somehow, perhaps in an abstract, non-intuitive way) associated with “a classical piece of matter”? And since the very definition of wave function is, in the generally accepted and most commonly used view/understanding/application is that it’s a mathematical description of the quantum state of an isolated quantum system. So how you can possibly try to associate a wave function with anything classical is an explanation and concept about which I’m most certainly looking forward to gaining some small amount of insight.
Well put. Why didn't they just said that?
@@florinadrian5174 Da, ai drepate, de ce nu s-au gandit?
Superb...You should be paid for that comment....tu
It took me many rewatches to fully grasp, but this concept is brilliant. It feels like it almost elevates the universe (or any extensive system) to the level of any observer, whether conscious or not.
Vishnus Dream.
took me many rewatches to get it into my head that Schrodinger was black! who knew?!
It's like a dream where the dreamer is both the dreamer and the creator of the dream in a feedback loop. The only difference is dreams are fleeting, whereas waking reality persists and continues to build in a reasonably consistent way, until someone like Einstein comes along and says here's a crazy paradigm sift that fits, now let's go test it, and our view of realty completely shifts while also being completely consistent and measurable.
💟
This sounds a whole lot like Inception
Sh Boom life could be a dream
The concept of observation/interaction retroactively defining reality has always been really interesting to me, but not with quantum physics, instead, storytelling. Imagine this analogy: you're playing a video game, an RPG, and one of the characters asks what your player character's name is. You then get to choose your name, in that moment. But, within the story, that was *always* your character's name, for their whole life (presumably), and the only thing that happened there was that another person asked what it was.
Furthermore, there may be countless other players out there with countless other playthroughs choosing different names, all equally retroactively true to their specific game, or, perhaps, universe, but equally none of their characters will have any way of knowing about yours.
That's a great point. It reminds me of the "Neverending Story" (the book, not the film). During his stay in Fantasia, Bastian can wish for anything to happen. For example, for a knight who's trying to prove his worth, he invents a dragon who keeps abducting virgins and enslaves them until they die, and then he sets out to capture a new one. This dragon has now captured the knight's lady, and he has to go on a quest to save her. So, is that saying that the moment that Bastian wished for this scenario to play out, there has actually been such a dragon all along, and that Bastian is responsible for the miserable lives of all the women he abducted before?
Yes but there is still the code version, an ultimate defining base version named [null] who does all posibilities and none simultaneously, until the player runs and interacts with the code, creating the save that defines the character's life.
So in this analogy, we want to know the base code of the universe. the ultimate defining version that is all posibilities and [null] simultaneously.
That's why we keep trying to figure out where the universe came from. Knowing where the game came from gives you an idea of where to ask for the code.
What would be our equivalent of this?
I find the particles acting like a wave function untill an observer (conciousness) views it particularly interesting as it's more evidence for string theory if you ask me.. I think we are 3d beings in some 9-10d universe.
This is a great analogy for what would be happening in a wheeler-type universe
Man the reason this channel is better than most others is because it never ends the video unfinished: he always explores the subject satisfyingly fully
Fascinating! Wheeler's negative 20 questions reminds me of a Wordle variant called "Absurdle" which uses your guesses to narrow down the space of possibilities. It's maximumly challenging to get to an actual answer.
I believe from what I have seen so far from may science movies that many things are emergent like Time and gravity.
Haha, yes I also thought of Absurdle! Of course, the difference being that Absurdle is deterministic and picks the answer that gives the most options, while the universe 'randomly' picks from all possible answers, with weight given to more likely/possible answers.
I very much love the fact that our observation of reality meets ancient philosophy. In this video I was reminded to a nice buddhistic idea: The experienced object, the experiencer and the experience are the same.
Please keep on making cool videos space time team!
I wonder if you fully understand that the word "we"means indicates or signifies the user of the term - that is you sunshine, and his immediate interlocutor, and since you have no immediate interlocutor, "we" can only indicate will be replaced with "I", or it is entirely imaginary.
In the instant circumstances do you agree that you have no direct immediate interlocutor therefore when you refer to "we" you are phoned to yourself and absolutely nobody else whatsoever.
Do you understand that?
Why are you creatures so terrified of the perpendicular pronoun "I"? Why do you seek to hide behind some fantasy "we"?
Yes, because of the quantum fields
@@vhawk1951kl ...Did he use "we" in his comment? I'm confused.
The Buddha and Krishna knew what they were talking about, but they didn't have the words to describe it
if anybody wants to know what dogma looks like you can find a pretty clear image of it at 11:11
always fun to see modern physicalists contortion to refuse the logical idea that there exists only one consciousness in the universe, which would explain everything, but sounds too "mystical" for their dogma
Thanks to PBS for all the high quality super educational videos. One of the best channels of TH-cam.
This was truly a stellar episode, I'm absolutely certain it was one of the best. Thank you so much for giving me something to ponder. I'm not very well schooled, but I'm very curious, and your show always gives me such tantalizing thoughts to consider.
This video was woke propaganda
I agree, excellent video, I didn't even know Erwin Schrodinger was black until now!!
@Praise Jesus, Repent or Likewise Perish
Thanks for sharing M, and its warms me to the cockles of my heart that you are saved in the blood of the lamb... but this is a conversation about physics... are we perhaps off our meds, or would you like to speak with someone about how Jesus and Quantum Mechanics are connected?
@@ChildOfTheLie96
I'm hoping this is the most hysterically sarcastic thing anyone has ever said... because if it's not, you've just invented the negative IQ. Which is actually impressive, besides dark matter, dark energy, and antimatter, the negative IQ poses serious physical questions;
That if an observer with a negative IQ observes an event in the universe, do they de-collapse the wave function???
Inquiring minds....
Ponder the reflection in the mirror while you can, the rest is irrelevant. °Ö°
Matt: We have determined that our universe is created from answering questions.
Matt shortly later: Please answer our 8 question survey.
Matt next episode: Physicists have just discovered 256 new universes.
Lol
In Rick Sanchez Voice: "This guy gets it."
@@pbsspacetime aaaaay, finally, a cultural reference.
42
In the game Oathlords, which you should play immediately, "God" is called the Dreamer and nothing exists until it dreams of it... or really imagines it. The elves are immortal because they were created before the Dreamer thought of death. The humans came just after. The universe began when the Dreamer first differentiated solid from ether, Erdfader and Etherdrottning, and liquid was formed in their embrace, water being associated with balance and life. But anyway... the universe is just an evolving awareness of possibilities which become realities.
I find it strange to present observation in terms of "conscious beings" *first,* and only then go back and consider the possibility that observation is just interaction. The latter seems vastly simpler and more coherent.
Apparently, the universe was around billions of years before “conscious beings “ existed. Indeed, interaction is the definition of observation, even in this video .
@@Boogaboioringale correct. The philosophical dilemma only exists if the observer is necessarily conscious. Which of course is absurd because that would necessarily require consciousness to somehow be supernatural.
Interaction between non-conscious objects, however, does not cause the collapse of the wavefunction. @Kerry Fitch The universe was around for billions of years only as per our observation collapsing it into such a state. We have no way of knowing what exists outside of our conscious experience and observation.
I don't know exactly when it started, probably somewhere around the Enlightenment, but science took a hard turn in trying to distance itself from God and thereby put humanity at its centre, as we and our senses are the instruments that scrutinize and measure the Universe. We can only know what we as human beings understand. This has its roots in Descartes, the guy who said "I think, therefor I am".
This has been criticized by conservatives (ironically), but also by writers like Lewis Carroll (Alice in Wonderland) and H.P. Lovecraft (where humans' brains literally start melting or they go completely crazy by the sight of gods visiting Earth). For the Ancient Greeks, this was never questioned, because they saw science as a mere tool to improve their technology. However, modern society sought to replace Christianity with science, and this has created the society of experts we are rife with today. City planning, psychology, sociology, everything that can be mapped or turned into a logical system, will be, and our society relies on experts to solve these "problems" so someday, we can have heaven on earth.
Slowly, through the quantum, God has come back into science. We are living in an age where Enlightenment is fading, because we have scientifically proven science cannot rid us of all our problems. There is no technocratic valhalla waiting for us, we simply have to deal with this Earth as it was given to us and respect its own laws that tie us to her. For the first time ever, there is mathematical proof that the optimism of science is mere philosophy. It portrays a version of reality that makes it easier to understand, but it is not reality itself. There are paradoxes, now perhaps even some that science cannot find a way out of, and some people are freaking out that their own set of logic has presented them with a paradox that cannot be solved. Let that sink down: a paradox that cannot be solved. Scientists cannot, and will not, accept science that contradicts itself, even if it is true. If you were trying to solve a paradox in philosophy, people would laugh at you. Paradoxes exist for you to learn and accept that your field is merely a representation of reality. Yet it is the fruit of science, technology, that makes scientists believe their way is the only way, and because technology is everywhere, people have come to accept this statement as well.
They are absolute morons if they cannot accept science proves a lot of things, but not everything. The sooner you learn that, the sooner you can start to learn to understand the world with your heart and your soul instead of exclusively your mind. So consider yourself lucky for not having problems with such an easy question, because apparently there are a lot of people out there who have a really hard time dealing with that kind of stuff.
@@CommandoPootis
"We have no way of knowing what exists outside of our conscious experience and observation."
By that same reasoning, I have no reason to believe you are anything more than a single comment on the Internet that itself only popped into existence when I read it. If you want to be intellectually honest, you have to take it to its conclusion, which is to completely disbelieve in anything that you are not actively, directly observing, including any other consciousness, and deep suspicion of even what you observe because you might be hallucinating it. If that's the position you want to hold, feel free; but it's not a very useful one, and taking a little part of it while ignoring what the reasoning ultimately leads to is NOT consistent.
Have long felt this way about the universe. I wonder if the set of "questions" that can be asked by each physically real particle, A, is constrained by whatever interaction collapsed A to begin with. Say B is collapsed into a 4 by C asking "what is a number between 1 and 10". Now B can only ask "what is a number between 1 and 4", A answers by collapsing into a 2.
This is a ropey analogy suggesting that electrons and photons are electrons and photons, because whatever collapses then to begin with can only "ask" a very narrow range of "questions", i.e the probability space is very tightly constrained by prior interactions.
This may seems a little obvious, but then perhaps you can go far enough back to eventually define a singular interaction describing the big bang. In a pre-universe information space where all possible "questions" can be asked simultaneously, one of the "answers" will inevitably collapse into the universe we observe.
As an aside, is it possible for a complex enough computational engine, fed information about other previous interactions, be able to further constrain the questions it can ask, in order to increase the likelihood of a particular answer. In other words, could a defining feature of consciousness be a weak form of "free won't", avoiding already "asked questions" in order to arrive closer to a preferred answer, on a macroscopic level.
You say narrow but you can argue numbers between 1-4 is infinite, the infinite bubble is smaller but still infinite. Which I think it is how the questions/answer pool is 3^n infinitely because there are 3 answers true, false, undefined (paradox perspective, ping pong contradictions) to one question. Even equivalence is not specific enough 1=1 can be true and false in an infinite number of ways by observational perspective changes
@@AskEpic well I guess that depends on whether reality, and/or the probability space for a given system, is infinitely divisible or discrete. Though I do want I say I used numbers as discrete integers for the purpose of this analogy, and didn't mean to imply real numbers with infinite values between each one. I should have used letters instead.
Does this have anything to do with particles travelling at the speed of light? My thinking is that since photons travel at the speed of light and thus have no experience of time, the "point-like" instance in which they exist needs to be completely defined before they can have any kind of meaningful properties. Does that make sense? Like, imagine a photon that existed some time right after the big bang, and is absorbed by a photon detector in the present day. From the photon's perspective, its entire existence from its reference frame is still a single instant from the time it was emitted to the time it was detected. But if the photon detector is removed, the photon still exists for a single instant, but that "instant" isn't defined yet because the photon hasn't been measured. There's no "end" to its journey yet, so it isn't "defined." Man all this stuff messes with my head, are there any physicists who can help?
I really hope Matt answers this question. I'm just as curious now!
Roger Penrose came up in part of his CCC theory based off the seeming paradox of a photon that goes off into infinity.
Indeed. photons only take time to travel because it has interactions with any other particles in the universe.
if it was literally alone in the universe, it would not experience ANY time at ALL.
This made me realize something funny about time and gravity. Time slows down in gravity and it's said that it's time that causes gravity and not the other way around, you could say that time dilation is the universe literally slowing down the clock speed to calculate all the interactions without errors like a computer would :Þ
The game EVE Online actually does this haha.
You need a physician, not a physicist. To deal with the headache, I mean.
(BTW - I think part of the headache is that you can't really say that a photon has a "point-in-time-like" existence from the standpoint of an outside observer; that's only true from the point of view of the photon; if we moved at the speed of light, our consciousness would necessarily be very different, if it could exist at all)
This might be the essence of the wave function. Photons are in a state of "superposition" existing because of a future particle interaction making it's reference frame "defined", yet before measurement is still in a state of nonexistence since it's reference frame has not been "defined" yet.
However, considering the fact that universe is expanding faster than light, some photons may be traveling through the void of space making the point of there existence never "defined. It would likely depend on whether or not photons are eternal.
Really interesting theory! I think that some of the issues with this (and many other quantum theories) is that some terms are not well defined: what exactly is an observer? A human? I sure hope so! A cat? Probably. A tree? Maybe, it can react to changes in it's environment. Is that observation? If so, almost everything is an observer! A bacteria? A virus? Even a chip in a computer reacts to it's (electrical) environment. And not just electrical if you hook up suitable sensors. Hopefully we can come up with a good scientific answer to this. And no one seems to know what consciousness is! It seems to me like these questions are tightly coupled with many of the attempts to interpret quantum mechanics beyond "shut up and calculate".
If 2 pebbles collide & 1 sustains a dent, is that considered a measurement or observation? If 2 particles collide & change trajectory, is *that* considered a measurement or observation? IMO that finally solves the q “what if consciousness had never existed”?
Consciousness (as in awareness not mental activities) is just when something’s state changes in response to information from its interaction with another thing, or better stated when something’s (object a) state is changed in from its interaction with another thing (object b) it gains information of that other thing (object b). When scaled up to neural networks which gather external information and synthesize it into a multidimensional matrix (as in there are many datapoints) that represents the outside world (our experience), it makes sense how consciousness derived from particle interactions. The things experiencing the information would be the particles that comprise the neurons which receive the information.
U1
Tbh I don’t know why this channel so frequently focuses on outdated speculative woo no modern working physicist actually cares about.
It’s not just “shut up and calculate”, it’s that when all you have is philosophy and thought experiments and can’t set up actual experiments to prove or disprove your points it ceases to be science.
Einstein started with thought experiments to formulate and explain his ground breaking theories but eventually we moved on to countless empirical evidence those theories were right. What can’t be tested sooner or later gets discarded and for the little I know, some of the arguments that Matt presents to his audience as still fresh and relevant, have already been discarded a while ago.
@@w315burd then maybe none of it actually happened!
This is reminiscent of "lazy execution" in computer science, where a piece of state is generated on-demand instead of being computed every time there's a change to the system. For example, a rectangle defined by two points on a 2D plane, where the object is manipulated by moving the points around, but every 100 manipulations or so the program needs to query the width of the rectangle. The object can store a "dirty" flag, which indicates that its remembered width is out-of-date. Any time there's a change to a point, it sets the dirty flag to true, then when the width is queried it checks the flag. If the flag is false then it returns the previously calculated value, but if the flag is true then it calculates the width, remembers it, and sets the flag to false, then returns the result of the query. This makes the query itself more expensive, but because the query only happens 1% as often as the manipulations, it results in an overall savings, since the width isn't constantly being recalculated when there's no use for it.
You can't make a rectangle with two points
@@Nomadmandude You can define a rectangle with only two points assuming the points are the opposite corners.
Yep I'm constantly struck by how much like the inside of a computer our universe looks. Makes you think.
@@glenneric1 How about Earth? With our communications network we now have we kind of operate like a hive mind, or a big, slow computer.
@@Nomadmandude You only need to store information about a pair of opposite corners. The other two corners can be inferred. Useful if trying to save space when storing, say, a trillion rectangles for some reason.
If, going clockwise, corner A is at (4,10) and corner C is at (7,5), and that's all we know - we can infer the rest. This is a 3x5 rectangle (xA - xC, yA - yC). We can also determine corner B will have coordinates (xC,yA) and must be at (7,10) and corner D will be at (xA,yC) or (4,5).
visual aid: www.desmos.com/calculator/geukrvlspu
We are living self-conscious processors of Information, in a Universe where everything is Information and Energy, and where, if there is a purpose, it could be characterised as “Information seeking understanding through experience”.
Dat was poetry, so it were...
Well put.
Do you think the Big Bang was “GOD” becoming aware of its own existence?
(GOD being a stand-in for the ineffable ground of all being, be it trinity or flying spaghetti monster)
@@thelawfus I conceive of the Quantum Foam and Eternal Inflation as being like a pot of water simmering on a stove, with bubbles constantly forming.
Physicists define the line between the finite Classical World and the infinite ‘Quantum Foam’ as ‘The Heisenberg Cut’.
Our ‘Classical’ World, one of a myriad of ‘bubbles’, is defined by limited information (34 constants determine the standard models of Particle Physics, Classical Physics and Cosmolgy), constrained possibility, finite potential and one jolt of useable energy given by our ‘Big Bang’.
Studies near ‘Absolute Zero’ show that the fundamental rule that necessitates space, the ‘Pauli Exclusion Principle’ disappears, and that matter can exist in a state of ‘Superposition’ (a ‘Bose-Einstein Condensate’)
Absolute Zero is by definition the barrier where there is no motion.
On the other side of ‘Absolute Zero’, as there is no motion, and there is no need for Space or Time: there is only ‘Pure Information’- existing in a Singularity of Superposition as a ‘Quantum Foam’. In Spiritual terms, a Supreme Consciousness: an emptiness, a void, outside of Space and Time. ‘Brahman’, ‘God’, ‘Nirvana’, Plato’s perfect forms and Spinoza’s Substance are all conceptual ways of trying to describe the same state.
@@thelawfus I'm thrilled to find this viewpoint somewhere else than in my own mind. Only that I had imagined the Big Bang as the universe achieving the peak of consciousness, thus "creating" GOD, who consequently created the basis for the universe's and thus his own existence. Assuming that time is non-fundamental, of course.
Perfectly mind-blowing topic for today
If we leave in a participatory Universe why the Univers creates the Aliens for us since we look so hard from them and we don't see and clue that they exist or existed whatsoever since we peer with out telescopes into the far reaches of space and time
Question: Under this interpretation, does this mean that photons should be thought more of like a probablistic constructive ray trace from point of measurement? (So the measurement builds the reality, not the reliaty causing the measurement)
As in, in a extremely simple and young universe; the first measurement is made, it is that of a red photon, this in turn creates the possibility (however low) that one of the following, but not limited to, exists:
-A thing that emits red photons all on its own
-A thing that emits photons, that hit another thing that absobed it and emitted a red photon
-A thing that emits blue photons, but is acceleating away so quickly the photon is red shifted
-etc...
And as more measurements are made, that support one of those possibilties, the more likely it is to exisit, and because they'll be interacting off eachother, existance will eventually come to a semi-'agreed' upon state?
This is very interesting indeed! There are some similarities to what computer science refers as "capabilities based computing" and your ideas.
In a capabilities system, there are rules that all members follow (for example, the amount of energy needed to produce blue light) and the final state (the "reality") is constructed from the initial set of events given.
In your example, only a single path of possibilities would be permitted and that would be what we observe.
If you wish to understand capabilities a little more, I highly recommend looking for videos about "wave function collapse" for video games (totally unrelated to physics, it's more about constructing game maps from basic rules)
Hmm, your comment it making me think of another strange possibility. Maybe we are experiencing time backwards (what seems to be forwards to us)? Is it possible that the minimum entropy of the big bang is the final state of the universe?
By looking up at the clear night sky, you are emitting photons perfectly towards the impending collapse of all things.
@@TheXello sounds very intriguing. Would you care to elaborate further how you see this as being?
I believe from what I have seen so far from may science movies that many things are emergent like Time and gravity.
@@nsk370 well if the laws of nature are time symmetrical. Then it doesn't really matter whether we are guided towards minimum entropy or maximum entropy. As we experience time, to us it makes sense that we are heading towards maximum entropy. But that is just the way that time flows in our perspective. It could be that our time flow perspective is reversed from the true flow of time. Granted this is very far-fetched. And I definitely wouldn't place any bets on this idea.
Question: how would the delayed choice experiment work, or be interpreted, in pilot wave?
My two cats and I are in a “superposition” of loving and really loving these videos!
Penrose mentioned in an interview with Peterson how there are observations with 99%+ confidence from earlier universes in the CMB. A couple of 'spots' from the Planck observatory iirc, and they would be the leftovers of supermassive black holes in the former universe. I cannot wrap my mind around this, please cover this in a video! 😍
The participatory universe theory gives further weight to the notion I’ve held most of my life which is that the universe is a ‘context’ that allows it to observe and experience its own endless possibilities. Or as Brian Cox would say - we are a means for the universe to come to know itself, an idea held by some cultures for thousands of years. The oldest ones are often the best 😊
Lovely man Brian Cox, and a dreadful dreamer and the funny thing about his dreams is that he supposes them to be something other than dreams.When a man supposes that an image that is *only* an image in his associative apparatus is something *other* than an image, he takes what is no more and no less than image to be that *of which* it is an image. That is surely axiomatic.
It is exactly the same of words; men suppose that because they have the word they necessarily have the meaning or can directly immediately personally experience what for which the word is only a symbol.
It simply does not necessarily and inexorably follow that because you have the word you necessarily have the meaning or corresponding direct immediate personal experience which exactly matches the word and the associations that that word evokes in your associative apparatus.To be perfectly brutal and blunt, that simply is *not true* or the case.The fact of the matter is that images and words obscure more than they reveal - it is unavoidable that is the case, because that is the whole*point* of them.They act as proxies.
Cox actually got that from Carl Sagan I believe.
woopie doo - an argument from someone maybe smarter than you gives a preexisted thought of yours "more weight".
confirmation bias mixed with appeal to authority.
Kind of wish this would be more regularly couched by 'interaction' rather than observation. Despite the quantum 'fuzziness' of the existence of individual particles as they dash through the universe (or tabletop light beam experiments), most things WE experience have a much more significant and solid reality - because all the particles that make up us and our environment are interacting *constantly*, billions of times per second. This prevents any sort of 'quantum fuzzy woo' from cropping up in our lives, because all the stuff of us and our world is essentially pinned down by these interactions. Only when you get into rarefied experiments, or photons traveling endless light years through space does this sort of quantum observer/interaction weirdness generally become relevant.
Honestly, Relativity already told us that interaction is critical to the underpinnings of reality - it's literally right there in the name - because you cannot define the properties of any particle EXCEPT as they relate to some other particle! That relationship and their interactions between each other are the actual important part. All forces and vectors are measurements between particles, not of particles. You can't even measure the mass of a particle in total isolation, because even mass is a relative value, as seen by the way particles can gain mass as they approach the speed of light.
Completely agree. It’s like they intentionally choose words that would mislead any lay person to think that consciousness determines reality instead of interaction, like you said.
@@johnsmith7303 They are not choosing words to mislead people.
I don't think we should confuse interaction with observation. Particles don't care if they're interacting or not, neither do they care if they're real or not. An observation is not just a measurement or a recording. It's the act of a sentient being perceiving an interaction or an effect and objectively reflecting on and reacting to it to predict the future. Self-reflexive consciousness is such a weird, crazy, exasperating phenomenon. It's not that the universe isn't real without conscious observers to perceive it, it's that the question is totally meaningless without any observers, because there's no one around to ask any questions in the first place. We can meaningfully question the nature of reality now with us around to observe it, but whether eg the universe was real before we were around to perceive it? Forget it, just shut up & calculate.
Quantum Darwinism for the win! :D
I watched the video, no need to timestamp anything. And obviously I’m not saying they are literally trying to mislead people, but they do intentionally use terms that inherently gatekeep this kind of info. The ONLY way to observe something is to interact with it, which is why they send particles down a vacuum in these experiments. But instead of stating “The particle is in a superposition until we interact with it,” they say “The particle seems to be in a superposition until we observe it.” This DIRECTLY leads to people putting an emphasis on consciousness rather than the interaction required for the observation.
As for the timestamp, it demonstrates my point that he’s having to clarify what he DOESN’T mean when he could just use more accurate terminology.
Fabulous. This is Esoteric Buddhism. The mind creates both the observer and the subject. ❤️🙏
Non dualism at its finest. We are the universe experiencing itself ☮️☯️👍
It's marvelous seeing the convergence between the scientific study of physics and Buddhist cosmology. It makes you really appreciate how brilliant people must have been thousands and thousands of years ago.
How is it that the beam splitters from Wheeler's thought experiment (and real experiments like the quantum eraser) do not themselves lead to the collapse of the wave function? The photons must interact (or not) with the atoms at the beam splitter. When they do, the photon is absorbed and a new one comes out. Intuitively, it seems that the atoms of the beam splitter have measured which path the photon has taken.
There is clearly a matter-energy field wave medium that pervades space and photons are obviously a ball of compression energy that causes a field stretch that can reflect, refract, diffract and interfere with little or no loss of energy to the compressed energy ball focal point.
--
The beam splitter always randomly reflects the focal point or lets it through, so a random path is always followed. The accompanying field warp / pilot wave is 50% reflected, 50% let through the splitter. When the extra splitter is put in place the diffracted, preceding field warp recombines with constructive interference, forming a wave guide that ensures the focal point always hits the same detector on the right hand side (going by the diagram in the vid), no matter which path the focal point took..
--
Double slit is similar. Preceding stretch-compression field warp / standing wave(let) is large and goes through both slits, diffracts and interferes, forming wave guides (rough and calm field)... The wavelet focal point only goes through the slit it is aimed at but only a tiny amount of quantum randomness is enough for the focal point to randomly hit a wave guide a follow it.. Putting another detector near one of the slits interferes with the wave guides so the focal point goes straight.
@@PrivateSi I like the way you think.
_"When they do, the photon is absorbed and a new one comes out"_ - the photons are not absorbed, and new photons are not emitted. The (QM probability) wave of the photon induces waves in the electrons of the material. And the induced waves then interact with the wave of the photon again, affecting the behaviour of the photon. See Fermilab's excellent explanation of why light refracts in glass: th-cam.com/video/NLmpNM0sgYk/w-d-xo.html, and think "probabilities waves", instead of the EM waves he talks about.
But it touches on the main question: "when does the probability wave collapse", that is: "what is a measurement?". Or in this experiment: "why does the photon detector make a measurement, but the beam splitter not". The answer to that is not known yet.
@@PrivateSi Just to clarify for others, this is called the "pilot wave theory". Look it up to learn more.
@@renedekker9806 .. It is my variation of Pilot Wave Theory extended to the Quantum Eraser Experiment.. I've been pushing an Electro-Positronic Matter-Energy EM Field theory for years under the radar in forums... Electrons and Positrons are the only known proper permanent fundamental, elementary particles with definite intrinsic mass.
--
Quarks have never been seen outside a Proton / Neutron. Many experiment results SHOULD lead to the conclusion that all compound proper matter is MOST LIKELY made only of electrons and positrons. If you want to discuss this you are welcome.
--
A load of old +ve charge balls (field cells, quanta, base charge +1) close-packed by free-flowing, compressible, discplacible -ve 'gas' (Pixie Farts / Electron Gas).. It's a Realist, materialist, mechanical model with the electrostatic Coulomb force as it's one base force from which all other forces emerge.. It's a self-balancing field under tension.
--
Many Standard Model variations are possible from this MOST SIMPLE FIELD possible from which to emerge Standard Models... My models stick to definite facts. I can explain phenomena possibilities using the model. Mainstream theoretical physics is deeply confused, that is a definite fact even they'll admit. Particle Entanglement and Photon 'entanglement' are very different in my main variation.. AC field vibrations in a 'flux tube' between charged particles vs what I described about QE and DS Experiments.. Wave Guides,
I absolutely love how this channel does not shy away of this kind of topics. Big up
didn't this channel debunk hole observer control magical universe
I wish he would talk more about why there haven't been any real fundamental breakthroughs/discoveries in physics in 40 some odd years.
@@stopthephilosophicalzombie9017 it's mostly because we don't have any testable alternative theories. Up until very recently every experiment, at least in fundamental physics, has supported the current theories. For the holes we do have (dark matter, etc) no theory has been proposed which explains every experiment we already knows the results of, explains the phenomena we can't yet explain, and it's testable.
Testability is probably the biggest issue. That's why we are trying to look farther in space and need bigger super colliders as these will allow more detailed experiments and observations.
what topic? Idiotic interpretations?
@@maythesciencebewithyou metaphysical speculation
The delayed choice experiment ceases to perplex if you consider Relativity. The time elapsed from a photon's creation to its demise, from the photon's perspective, is always zero. From the photon's point of view, the decision of how to behave, and the measurement, happen the same instant. Has the delayed choice experiment been repeated with slower particles?
Interesting point. Atoms can be entangled, so it seems slower than light items experience the same instantaneous effects.
This video better explains the quantum eraser th-cam.com/video/0ui9ovrQuKE/w-d-xo.html
yes, De Broglie showed that any quantum effect also works with the other particles and can be extended to packets of them, up to regular objects. The effects even out, and that's where quantum becomes classic, but only gradually so, although in discrete steps.
@@scififan698 I know that experiments like the double-slit have been done with slower particles. I still think it would be a good thing to verify delayed choice with slower particles, though, to rule out once and for all the relativistic angle. But I'm not a physicist; just an interested bystander.
The fact that experiments like the double-slit experiment is repeatable with particle that have mass shows they are also in a superposition of states and that there's nothing particularly special about photons in that regard. This in turn suggests there is no reason for us to believe particles with mass would behave any differently the delayed choice experiment.
I've loved the statement by Carl Sagan:
We are a way the universe can know itself.
This episode reminded me, strongly, of when I first read Wittgenstein's 'On Certainty'--that we enter into a language game to build shared understanding (agreement) of a thing. Philosophical skepticism, then, actually can be addressed. To suggest that a "reality" may emerge from us course-correcting our way toward a shared 'something' via our inquiries makes sense. That path is legitimate when facing genuinely 'wicked' and complex problems.
I believe from what I have seen so far from may science movies that many things are emergent like Time and gravity.
Wittgenstein was a beery swine who was just as sloshed as Schlegel.
I’m convinced that we are the result of an infinite imagination where nothing makes sense until we try to make sense of it. Much like our brains make sense of random thoughts that somehow coalesce into a dream reality.
One interesting thing I'd like to note is that this seems to map precisely onto a similar question in mathematics: Are we creating new mathematics, or are we discovering already existing maths?
The answer seems to be roughly similar, too.
You mean mathematics is a participatory entity ?
answer is quite obvious, math isn't invented but discovored
Philosopher Alan Watts puts it much more succinctly: We see the universe not as it is but as WE are. Consciousness in the present moment is the basic reality, it plays with itself by making up stories about its own existence. The past emanates from the present the way a wake emanates from a boat-- it shows us where we've been but does not propel us forward.
I‘m a mathematician, and I struggle hard to get a straight answer from physicists on the following questions:
1. given an observation, how do you calculate forward or backward the wave function in time? Is that even meaningful?
2. Is it fair to compare quantum mechanics to a hidden Markov model if you replace the Markov transition operator with some unitary operator and the emission operator with the absolute square of a projection?
If 2. is the case, then in my mind, the mystery would basically go away. If you think about it, a hidden Markov model is (just like a Markov chain) just an encoding of the statistics of the observable marginal process. Often, the hidden process is entirely made up and just serves to reduce the complexity of the data to something that we can deal with mathematically.
The same might be true for the wave function: even though you kinda need it to effectively calculate the statistics of quantum measurements, it may be entirely made up. Note that one doesn’t have to treat mathematics as „just a language“ or say that physical models are always „just models [that don’t say anything about fundamental reality]“. One only has to know when to make this distinction.
If my speculation is correct, we might learn something about fundamental reality by analyzing the class of observable processes that quantum mechanics encodes. However, I wouldn’t expect efficient predictive algorithms from that.
Physicist here.
So for point one: the "collapse" of the wavefunction, or in other words the measurement of the wavefunction in a specific basis with a specific outcome, is a non-unitary process; you can inherently not calculate backwards. Calculating forwards is straightforward given the state into which the system was projected; this is done according to Schrödinger's equation.
As to point 2, I'm personally not familiar with the emission operator, but a relatively recent theory paper has proven that only a theory using so-called "local hidden variables" could produce a more complete description of the world than quantum theory. I think this is what you refer to by "hidden model"? The Wikipedia page about hidden variable theory is quite informative.
I'm no physicist but even I can tell you the answer to the first one, time symmetry alone can be broken, in fact only CPT symmetry appears to always hold, meaning some events are physically different going forwards or backwards in time, once you add causality into the mix you have a clear arrow and distinction between forwards and backwards in time. An example of time symmetry being broken can be found in the flavour oscillation of B-mesons.
@@TheBmannumber1 Although the result of wavefunction collapse is non-unitary, the time reversal function of the time dependent equation is anti-unitary is it not? So depending on your interpretation of the question posed there is meaning to solving backwards in time, no?
I struggle with the following… since photons travel at the speed of light, they dont experience time, so by measuring/interacting with it, we modify its whole existance… its not that the wave function is collapsing, its that the object/wave has been interacted with, modifying its whole existance?
@@TheBmannumber1 In the theory of HMMs, calculating backward isn’t achieved with a transition matrix (the classical analogon) either. It’s an entirely different process known as „conditioning“ or recursively applying the „Bayes‘ rule“.
I know about Bell‘s refutation of local hidden variables in a classical statistical setting. I‘m not interested in a such a classical theory, but I would like to understand is if one can generalize inference rules to a quantum setting, or possibly even beyond that.
This is one of my favorite episodes. All I can surmise is that the universe is really creepily weird and wonderfully fascinating!
If only you had some clear idea of what you seek to convey when use the words" the universe", but you are about to demonstrate that you have no clear idea of what you mean by " the universe", probably because it is imaginary and no more than a vague generalisation. All universals are, and can only possibly be imaginary(vague unfocused generalised ideas/associations/images in the associative apparatus/function, or mind), In essence it is a portmanteau term and you have no idea what is in the portmanteau, or in plain teems you simply *cannot define " the universe" save in terms of vague generalisations
Yet you have no idea what you mean by " the universe" and cannot even begin to define it without resort to cognates synonyms, descriptions ans circularity
if anybody wants to know what dogma looks like you can find a pretty clear image of it at 11:11
always fun to see modern physicalists contortion to refuse the logical idea that there exists only one consciousness in the universe, which would explain everything, but sounds too "mystical" for their dogma
So the quantum eraser experiment makes me wonder if instead rewriting the future, there's simply a resonant harmonic in the time axis. We can't experience time as though it were a spacial dimension but that doesn't mean light can't also, especially since it experiences time all at once
It reminds me of a while ago when I saw an article saying that the ancient Greeks didn't see the color blue, as blue things were described as dark wine or something, and the researcher looked up ancient scriptures and found that other civilizations didn't either. they didn't had a word to define the color blue and so they could not distinguish it almost as if they were color blind, this would show that the language used would have a direct connection with the ability we have to perceive the world around us
This is a bit of a misconception. Colour categories vary from language to language and one language's colour terms might not necessarily line up nicely with another language's. The English word "blue" refers to certain wavelengths of light and excludes others, ancient Greek (and many other languages, extant and extinct) categorize what we think of as "blue" differently. Russian, for instance, has completely separate words for light and dark blue in the same way that we have ones for red and yellow. Vietnamese has a single term for both of what we would call blue and green. This doesn't mean that Vietnamese speakers can't tell the difference between what English speakers call blue and green, nor does it mean that Russian speakers can see "more" colours than English or Vietnamese speakers can. We all have roughly the same photo receptors in our eyes, we just semantically categorize them differently.
Here's an idea:
The past and the future(s) are the same thing. Imagine an arrow with the potential to point in all directions in time, different futures and pasts. Almost all directions lead to an higher entropy. There's only some that have lower entropy. Now optimize for the direction of the lowest entropy. Do a step in the direction of that arrow and repeat that process. It lines out the path to a state where the entropy is 0. There is only one shortest path. But there are many where the entropy gets higher.
Now the idea. I state that all possible paths exist. The question is why the universe's entropy was so low at the beginning of time. But was it actually? When you are thinking of the past you are just imagining an optimal path of many possible paths through time where the entropy is lower, and call that 'the past'. You can imagine any different path where entropy gets higher. All are equally real, so the one leading to entropy 0 as well. Why was entropy so low in the past? Because we define it to be so.
So you are saying that we observers experience the universe along the least-entropy path.
But I’m not sure how this path is defined when performing a quantum choice experiment where a hit on detector 1 or detector 0 is random and not defined by whichever event is of lowest entropy…
In short, can we prove that our path is the least entropy one ?
I believe from what I have seen so far from may science movies that many things are emergent like Time and gravity
@@francoislecomte4340
The path to the lower entropy is what we define as _backward_ in time. When the outcome of the quantum experiment happened and is known, the entropy has increased because it could have been a different outcome as well. But there's just one path to lower entropy, which leads to the state what we call 'before' the measurement, where the entropy was lower.
Question: Is space actually falling into a black hole like consumption, or is it just a geometry? I ask because if it's consuming space, then a possible universe inside a black hole could be observing that inflow of space as an expansion of space after the formation of the initial big bang singularity.
Yeah that's one of the ongoing theories about how our big bang is basically just a white hole. Also talks about a repeating big bang. Can't remember the exact name for this. Think there is a Space Time video or even a series for this exact topic.
It's not swallowing space, it is curving space time. The black hole isn't actually bigger on the inside, it's more like a funnel that makes everything past the horizon slide towards the singularity which would be the 'bottom' of the funnel. That would be a moment in the future, so basically it locks all spacetime paths (the geodesics) that go past the horizon so they all lead to the same point in the infinite future, which is why you can't escape. As more and more energy is introduced into the black hole, the funnel starts getting curved even more aggressively and the horizon, where the funnel starts, expands outwards, that is how the hole grows. But there is no additional spacetime on the inside than the outside of the horizon no matter where it is, the only quantity that is changing is the curvature which dictates which paths objects can take.
So the answer to your question is that it is just geometry.
@@zovisapphire Yeah I've been trying to parse how inflation could fit into it. The initial formation of a black hole shouldn't briefly stop and then restart under the event horizon, it's supposed to be a single event from our external viewpoint.
The only way I could make it work in my head would be the extremely brief period between the formation of the singularity and the gravity beginning to pull in the surrounding space, as gravity propagates at C, not instantly.
If there is a universe in the singularity then from it's internal perspective there would be a tiny delay from the formation of the universe until the external space begins cascading in. Perhaps that would give enough time for a CMB to form.
@@ThatCrazyKid0007 Where does the space in, and between the atoms go when it's all crushed down? Would be like wringing out a sponge. There would be extra space that was previously inaccessible, unless the fabric of space itself is also crushable?
@@NeonVisual It doesn't go anywhere, the space between atoms isn't getting smaller because the space is being 'crushed', it is because the curvature is so extreme it is forcing atoms to be closer and closer to each other. At one point the gravitational force is so insane due to the curvature that it is stronger than any quantum force like electromagnetism or the strong nuclear force and it crushes the atoms together so they take up the same position in space breaking Pauli's exclusion principle.
Episode idea: Could you elaborate on how Wheeler's "it from bit" fits in with the Bell-Kochen-Specker theorem, specifically thinking about work from John Conway and Kochen about a no-go theorem where there are sequences of observables that are mathematically impossible. If true, this seems like it might support Wheeler's interpretation. Is this even testable? Or is this something that quantum physicists don't put much weight in? I'd *love* to hear spacetime's take on this.
One of the challenges to the negative 20-Questions approach is that you cannot ask (or answer) questions in such a way as to arrive at a null hypothesis or it fails.
The universe cannot answer these questions randomly, or you quickly run into paradoxical answer sets, such as an object being defined as both bigger AND smaller than a breadbox, nor is it possible to ask questions in such a way as to force a null outcome.
Given that most outcomes are in fact mathematically or logically impossible from a given query state, these are actually pretty hard restrictions to satisfy, leading to rather strict behavior from most systems.
The crucial definition of Observation, that everything else hangs on, only gets an off-hand remark at 12:08 but even this is more than what most other content on the topic provides.
YES people brush off this entire concept because they don't understand this!
It's settled then. The tree falling in the woods does not make a sounds if no one is around to hear it. It is simultaneously fallen and not fallen until it is observed.
But surely the tree observes its own tall?
The tree falling in the woods never existed until you asked the question
I may be wrong, any scientists reading this please feel free to correct me but ive always thought that the sound is irrelevant. When the tree falls it leads to the sudden motion of molecules all colliding with each other. You need at the very least (as far as we know)
a human brain to gather the data from these collisions via small hairs in the cochlear of the ear and transform them into a signal that we can observe as sound.
it depends on your definition, a molecule bouncing into another molecule counts as an observation in quantum mechanics, so in that definition it still made a sound
Ah hah. You let the shroedinger cat out of the box!
There's another assumption in these questions that isn't acknowledged: that we can observe reality. Just as our eyes are only sensitive in a narrow range of the EM spectrum, our technology limits what we can observe. Our math says that particles exist as wave functions smeared across the entire universe. We acknowledge we have no way to observe that, but persist in acting as if it isn't true. What I've never heard is an explanation of how these wave functions interact in complex systems to create objects like people and eyeballs which appear as classical particles.
The explanation you're looking for is quantum decoherence, and it's as difficult to understand as its name makes it sound.
@@HaveYouTriedGuillotines sounds like a good prog Metal Band name :P
there have been a few episodes on quantum decoherence and this concept we're trying to understand: "when/where quantum becomes classical". As you can imagine, there's no perfect answer yet
Quantum-Mysticism was epicly covered by ‚Professor Dave’,
a great supplement to this video here,
which will in turn then hopefully lead you to his videos about the Discovery Institute,
which then may direct you to the TH-camr Telltale, who covers what you have just realized through this journey-through-youtube: Quantum-Woo and Science-Denial ccan be very deliberatete. I’m sorry my Try to spread Fun/Science sounds so much like ‚giving Homework’, haha.
Anyone that can reply that with total certainity will be a nobel prize winner and will change physics (and the world) forever.
I love how this episode portrays Dark Energy as that insufferable neighbour who we somehow need to live with.
You are everything that exists through this universe, everyone else is just a different part of you. Like a persons leg is to a hand
Wow, the participatory universe makes so much sense to me. This actually leads me to a very interesting idea:
What if all possible universes do exist, but this universe is just the one in which I, (my conscious mind) exists? What if the only objective reality is a superposition of all possible states of the universe that could exist? In some versions of the many worlds hypothesis, the wave function collapses from the point of view of an observer, when the observer becomes entangled with the particle that is observed. The only observer that I know for sure to exist is myself ("I think, therefore I am"). So what if the superposition collapses from my point of view into the universe that eventually produced me. And everything I interact with collapses from the superposition and creates my reality. This seems like some egoistical, solipsistic point of view, but it also could mean that all possible minds do exist in their own universe, where the superposition collapsed to create them. This whole idea is sort of an anthropic principle, but instead of arguing based on the fact that humans exist, I argue based on the fact that I exist.
There is no waveform collapse in many worlds, hence "many worlds". All minds existing in their own universe is most definitely solipsism, but that doesn't necessarily make it wrong either, but it does imply that this comment is produced by an unconscious entity.
Wait a minute...YOU'RE NOT REAL!!
(Queue Twilight Zone theme) 🤪
Don't be so self-centered 😀 hahaha. More seriously, the Transactional Interpretation of QM is what we are looking at here which is kind of a version of this participatory universe. The observer is not some "mind" but simply the only possible state that can exist.. and this has nothing to do with conciseness -- itself a neural net + specific input/output side-effect. Let's just say, if your interactions with the world around you were a little different, you would not be asking the questions you are asking. "Apple does not fall far from the tree" is probably more applicable here. I'm quite certain that a fly also "I think, therefore I am", but since we don't hear it or can communicate with it and thus make assumptions; it seems it does not have the same impact, right?
To put this another way, participatory universe means that universe does not exist until you interact with it. By "you" I don't mean *you*, but anything (proton, rock, etc). So yes, the Big Bang exists because we measure it. But we measure it because we exist and are a product of the Big Bang. Infinite logic recursion? 🙂Sounds like QM! 🙂 Now time to shut up and calculate!
you are basically describing the “many worlds” theory of quantum physics by sean carroll. he has some really good content on youtube, highly recommend checking his channel out.
@@Andynonymous_music no, here he's claiming that the entire universe from start to finish is in a superposition and the entirety of it collapses all at once into the one universe in which he exists making that observation etc. the moment he makes an observation
That makes a ton of sense and I agree completely
The Universe being created by its observers in essence means the Universe exists because its parts are interacting with each other. But I think it's the other way around. Observers exist because parts of the universe interact. I have no problems imagining universe without interactions, it would just be kinda dull. But there would be nobody in it to claim it's created by observation.
According to physics an observation is interaction. It’s the same thing.
@@ericpalmer3588 Yeah that's what I'm talking about.
I personally think the "answer" is somehow linked to the idea of emergence. That simple things combine to make more complicated. Ant vs Ant Colony, Quarks vs Molecules. This idea extrapolated "up" to the cosmic level seems like an obvious step to take... how to take this step is of course, more difficult.
Is not a more rational and better way of formulating the question as follows:*can*(whatever is meant by) "the universe" "create itself"? Is it *possible* for the universe to create itself and what does the universe create itself exactly mean?
Turns out that nobody has any idea at all either what can the universe create itself means or what "the universe" means or what they mean by the universe. You creatures use words without ever pausing to wonder exactly what they seek convey to you when you use them. No wonder you get so confused because you dream without clarifying your dreams or recognising that they are no more than dreams. They speak about "the universe" and when you ask them exactly what they seek to convey when they use the words "the universe" they can never ever tell you and the only possible explanation for that is that they have absolutely no idea what they mean by or seek to convey when they use the words "the universe". If you ask them what they mean by the universe they go in for psychological algebra or x=y=x, where both X and Y either have no value or are not defined or specified- They define one unknown in terms of other unknowns.
m>c9(+/-)~44÷9-/4[(-/+4)(8³-m²)]=cm>8÷T
Good luck with this one. Hope it helps. 😎❤️
Only a short derivation. The "end" equation is just a work of beauty. Mind you this is slightly simplified, but it's an important part to understand the rest of the function.
I'll come back later with more pieces.
I have some questions or ideas for an episode:
Time apparently relatively stops at the event horizon of a black hole. So time outside of the event horizon has to move relatitvely infinitely fast. But Black holes are evaporating. So it must be impossible to reach this point where time 'stops'.
Therefore, just before reaching the event horizon, there must be some kind of a firewall that converts all infalling stuff into Hawking radiation, and there can't be an inside of a black hole. What do you think bout this?
Also, an event horizon can form from within a collapsing core of a star. Doen't that mean that this core is exposed again when the event horizon has shrunk enough due to evaporation, the core of the star is exposed again as a neutron/quark star?
And one last one:
Does there exist a maximun temperature? As the wavelenght of the radiation reaches the plank level, it can't get any shorter right? And does that mean that blak holes that have evaporated to one planck lenght in diameter can never evaporate any further?
Interesting questions
As for the last one (does there exist a maximum temperature), I recommend you watch the vSauce video "How hot can it get?"
TL;DW at a certain point of heat, it simply collapses in to a black hole
Time doesn't stop at the horizon, that is a common misunderstanding. The relativistic effect for an outside observer is that time _appears_ to stop for an infalling observer when viewed from the outside because none of the photons can ever reach us again past that point, so there is a causal disconnection at the point the horizon is crossed.
However, for the infalling observer literally nothing changes when they pass the horizon, they wouldn't even notice (well, other than the insanely strong tidal forces that spaghettify you), but any information they could emit back to outside observers is trapped with the infalling observer as well because the spacetime is curved in such a way that nothing on the inside can leave past the horizon.
The problem is that there's too much wrong there. "Time" is not a thing that can stop, anywhere, and it is only the Schwarzschild global time coordinate that goes to infinity at the horizon, but this is unphysical. You can always switch to gullstrand-painleve coordinates where everything crosses the horizon just fine.
It is a requirement of GR (see Geodesic Incompleteness theorems) that everything inside a black hole vanishes at the singularity, so they're vacuum spacetimes (they're empty), so no core that exists when the BH evaporates.
Temperature can increase until the energy density is sufficient to form a black hole.
Here's an idea to look into: assume a base unit of spacetime -- say a "stixel" one planck-length in diameter and a unit of planck-time in duration -- but this has equal measurement in every part of the universe at a specific instant, whether matter/energy is present or not; also, while acknowledging that the ratio of this unit and the size of the universe would be infinite, assume that for any two points in time (X & Y), there is a finite ratio between the stixel at X & the stixel at Y. Finally, assuming all the other physical laws function in the usual way, just replacing spatial units AND temporal units with the the corresponding parts of the stixel, what's the difference between how an expanding universe looks and how a universe of constant size but shrinking stixel would look? Or, perhaps more interestingly, between a universe expanding where there is no matter/energy, or one where the stixel shrinks where matter/energy exists?
Eh
I believe from what I have seen so far from may science movies that many things are emergent like Time and gravity.
An episode on the question of "why is there anything at all" / "why is there something rather than nothing" and whether physics has the epistemic tools to answer it would be a great one, if you're looking for more ideas for episodes like this. Sean Carroll has some ideas on it
that one's easy. there is no such thing as nothing :)
I believe from what I have seen so far from may science movies that many things are emergent like Time and gravity
I believe from what I have seen so far from may science movies that many things are emergent like Time and gravity
I actually understood this, which is the first time, from watching PBS for an observable year!
Ive had this hypothesis floating around my head for a bit, and I wanted to get some input on it. This hypothesis is closely related to the Big Bounce hypothesis, but it varies in some aspects. Hypothesis: When the universe becomes completely uniform time will "reverse", eventually turning our universe into one with white holes, is dominated by antimatter, and is crunching in on itself. This could explain why we dont see white holes or much antimatter at all in our universe without having to resort to extremely complex equations that have yet to precisely model our universe. As scientists have already hashed out, reversing time doesnt make a difference in terms of physics. Reversing time doesnt break our equations, our equations actually work exactly the same if time is reversed. The only thing it does is change matter to antimatter and black holes into white holes. So whats stopping a fragile, uniform universe from not being uniform anymore? Whats stopping time from reversing when entropy has nowhere else to go? And when time is reversed and the universe eventually crunches in on itself, whats stopping the extreme environment of the subatomic universe from rebounding and time going forward again? This hypothesis differs from the big bounce hypothesis by introducing the concept that time can reverse when entropy ceases. Its not just "our universe will expand to a certain point then crunch back in on itself". This hypothesis argues that the universe will crunch back in on itself by time reversing when entropy can no longer make things any more uniform. Whats more interesting is that the previously reversing universe that turned into our big bang could have left an imprint on the CMB. Something that multiverse theory proponents say could only happen from a universe outside of our own. Well, now they have competition if we ever do find an imprint on the CMB.
@ Chris Johnson: excellent hypothesis. Entropy seems to have no choice but to reverse after reaching maximum. Also, the imprint could be the matter/antimatter “anomaly and the neutrino imbalance (only “left handed “ with a 1/10 billion chance of one being right handed [the same ratio as the matter issue]). This would imply that our universe is is far down the road in “cycles “ , maybe number 10 billion 👀
@@Boogaboioringale can't like this reply enough
Chris Johnson : I didn’t think about the entropy idea until you mentioned it. That’s very intriguing and could end up being more than just a thought...seriously.
In my view, the Copenhagen interpretation is realist to the extreme - perhaps even *more* so than the classical view. In the end, what it's saying is that an observation is a physical action, and the observer is part of the Universe and subject to the same laws as the system they try to observe. That was true already in classical physics; the new element introduced by quantum theory is that there is a limit to how *little* we can disturb an observed system and, what's more, the impossibility of measuring the effect of our action and retroactively taking it into account (in other words, we cannot even in theory reconstruct the state of the measured system *before* the measurement - we can only know what its state is *after* the measurement, which is what makes the measurement worthy of the name, btw).
I was thinking about what would happen in the negative 20 questions game if the questions ruled out all possibilities.
I suppose that would be equivalent to destructive interference.
Then the last question would be "does it exist?" And the answer would be "no"
@@nachoijp but the negative 20 questions happens backwards, you're using the rules of normal 20 questions.
If the yes and no answers to the questions always alternate and the questions are:
1) "Does it exist?" - Yes
2) "Does is exist?" - No
Does that cause a paradox? Or does the second answer override the first to prevent a paradox?
@@CircuitrinosOfficial tIf I understood right, the alternate answers was just an example, not a necessary rule. Maybe if you string a series of questions that end up in no possibility, then there's only one last significant question to ask (does is exist?) , and the answer would be no, because then previous answers made it impossible to get anything different
@@nachoijp maybe, but that's why I'm asking. The video didn't talk about that possibility.
I believe from what I have seen so far from may science movies that many things are emergent like Time and gravity
I think the discussion at around 13:10 really puts this in a good perspective. Quantum-level particles might exist in a state of superposition until we observe them, but they do still *exist* before we observe them. The particle doesn't pop into reality when observed; it just commits to one type of reality. So the realist position still holds up on a macro level. The "substrate," as he called it, exists whether or not we observe it. It just gets more specific when we do.
Maybe Spinoza was right: reality is a self-expressing self-signalling system! Thank you, John Archibald Wheeler! i wonder if Einstein and his obsession with Spinoza's metaphysics would welcome this information-theoretic version of Spinozian metaphysics?
Check out Dr. John Vervaeke's "awakening from the meaning crisis" lecture series. It's on his TH-cam page.
@@mathewhill5556 Thanks for the tip. will do
were strange loops
Langan's CTMU is the most advanced version of all previous metaphysics, Langan was inspired by Wheeler conception and also i assume Spinoza
Einstein was an idealist while Spinoza was a materialist. A good indication of Einstein's qualification as a philosopher.
Could it be that “observation” is a just a further entanglement that then binds your larger system to a smaller system thus “collapsing” the wave form? Sorry if that’s not very coherent.
That's basically what the many worlds theory says
I see what ya did there.
Could the collapse even be a form of singularity in itself? If information has mass a la dark matter, wouldn't a critical mass in this case be just like a mass of any other kind?
@@w4ffu1z I would guess that information can't have mass, due to the fact that it can be carried by massless particles (i.e. photons). Though I've heard weirder things in quantum mechanics, so I wouldn't write it off just off logic alone.
One man one universe. Or you can say nothing is real in the universe around you, and everything is your own imaginations.
This idea makes perfect sense to me. It seems like the same type of situation as general relativity. Without two different frames of reference interacting with each other, there can't be many judgements about what the "facts" of a given situation are. Am I stationary or moving at a constant velocity? Etc. Its all a little fuzzy and basically kind of meaningless unless there's another situation you can use for comparison. "Relative to what" is where the real action is. The fact that you can compare the two is what allows you to establish facts about either situation.
The "observer" thing is often misinterpreted, but I do think that its very reasonable to suggest that reality is relational, not objective. The facts about the world are established as a consquence of interactions between things, not by the things themselves. You might even say that there's no such things as "things themselves", its just relationships between things all the way down.
The Beginning of the Universe is like the End-- Irrational. This means it can be caused by reason, but will immediately assume it wasn't. There can be many, many irrational points and they will define other spaces more easily than be defined themselves. Therefore, the Universe can have a beginning, and an end, and they are defined, yet are more likely "form" and not hard edges. Fun! I enjoy your videos, PBS.
I'm not sure if there were deep, coherent thoughts beneath that, sounds like there were, but none of them made it to the surface
The only problem with the delayed eraser experiment is that you have no choice in the matter of putting the second splitter or not. So the photon "knows" exactly whether it will be there or not because the universe already decided it through it's infinite amount of initial conditions. Furthermore, from the point of view of the photon it all happens at the same time so there is no inconsistency. The trouble comes from the assumption that we are isolated from the wave function of... spacetime.
very low probability . it is just the same as saying the universe is spinning around the earth and the earth is not spinning .
"wave function of... spacetime." not sure what you mean.
two crucial information is needed to understand the delayed choice experiment ,
the detectors are polarization filters , they polarize light , but while doing so reduces or completely block the light .
to have an interference pattern two separate beams of light must interact .
you can look at the experiment again , and it becomes clear what is really happening .
You are assuming your own conclusion in the premise of your comment. That's circular reasoning.
Problem with superdeterminism is that it is not compatible with truly random probabilities (as you could use radioactive decay or the like to randomly, with no known variables to encode decision information, make the choice) which is hard to reconcile with the bell inequality in scientific way (de broglie pilot wave theory does not realy get to count in my book as it is not compatible with QFT so is not really a full interpretation of qm, plus non-locality is very gross)
@@georgesmith4768 It is absolutely compatible if the initial conditions are random.
@@m.c.4674 You can just put your reference system in sync with the spinning Earth, which is what you do when you look at the stars lol.
The wave function of space-time is the universe, I'm arguing that you cannot truly isolate two parts of it.
You don't need two "separate beams". My grasp in QM is weak but I believe all particle path calculations are done by calculating all the possible paths and seeing how they interfere. So in a way a photon can interfere with itself.
All interpretations of quantum mechanics results from the double slit experiment. I always go back to the basic experiment in my head. I always have a lot of new questions to ask after running trough the tought experiment. After I try to answer these, I usually end up with a new interpretation.
But first two important issue needs to be clarified for me:
1) Does every event horizon have some kind of horizon radiation (virtual particles)?
2) When we examine a single photon's light cone, what happens at the border?
I have a lot a follow-up questions...
1) yes
2) what?
The event horizon question is quite interesting actually! As we have an event horizon at the edge of our local bubble caused by the rate of expansion of spacetime, almost the inverse of the event horizon at the edge of a black hole, however off the top of my head it would seem that some of the rudimentary explanations for hawking radiation would still work for that horizon. As hawking radiation steals it's energy from the local curvature of spacetime around the black hole (thus decreasing it's mass) I suppose in this case the energy would be taken from the local expansion of space time (thus decreasing dark energy). Very interesting, however it would take some rigorous maths and physics to actually say whether this happens.
double slit and quantum erasure are my favorite two experiments because i believe they hold the key to our reality. And someday, I think Many Worlds will be proven.
@@DekarNL In a moving reference frame of a photon, future and past lightcones are also event horizons. What happens at those borders? Take Cherenkov radiation for example.
@@xxportalxx. Another question raises here:
Does the radiation coming from the ever expanding cosmic horizon creates 'new information'?
Imagine how the universe could look like to observers on such size scales where no baryonic matter is detectable - kind of when it could be explained as a "hypothetical energy soup" from perspective of observers of such large scale, that observing anything smaller than googleplex parsecs will be impossible to them.
I gather it would look like a glow in the dark petri dish
Beautiful episode. Been following this channel for years and it made me understand things in ways i never thought possible and opened allot of thought processes i never even dreamed of. Thank you for these PBSspacetime.
Idea: the programmer of our simulated reality implemented quantum mechanics as a compression algorithm. In that way they didn’t have to define all variables unless used (observed). And we’re all scratching our heads…
Deep
i keep having the intuition that it's more like a game where they don't waste CPU time on regions that haven't been explored yet. maybe a hot gas only has macroscopic quantities like temperature until somebody needs to know the velocity of a molecule? or until it makes a difference like cleaving another molecule? and the speed of light limit feels suspiciously like someone is compartmentalizing the universe so they can process chunks of the game separately
Gives an initial observation, as well. One from which our observed reality had evolved from. So even though our observations are relevant, they're still an eventuality of that first observation. Or am I way off?
good try, but surely a lazy programmer would have done anything but implement quantum mechanics! As Shor Quantum Algorithm shows, a relatively small quantum computer have an intrinsic computing power superior to all the classical bits existing in the universe
@@ags5377 you can't just compare computing power between quantum and classical computers. Quantum computing can only give you more power for certain specific situations, it's not generally mode powerful.
The only problem I have with the universe only determining it's characteristics under observation is that it's all constantly being observed. If photons move at the speed of light and don't experience time, then from the perspective of photons they're all being observed all the time, right? So how can we claim to observe or not observe something? It must have already been observed.
The observer effect is probably the worst choice of words for what it's trying to convey. It almost makes it sound like the universe is sentient, and only takes shape when it notices someone looking at.
The observer effect really has to do with the way light affects objects on a quantum level. We need to light to observe things, but the energy light carries can move or displace Quantum objects since they are so small. So the act of trying to observe quantum objects means displacing them with the energy that comes from light. So We can't ever really see what they were doing before we see them reacting to light passing through.
However the observer effect doesn't do anything at all to things we can see. In the big world that we can see with our eyes and telescopes, light doesn't carry enough energy to move objects around. Things don't move around your room when you flip the switch on and light certainly doesn't carry enough energy to make planetary sized objects appear out of nothing because someone looked in that direction.
The universe will still take shape with or without being observered.
@@bigquazz3955 Why don't physicists change the terms to make it easier? Asking as someone who isn't a physicist.
Metaphysics is Nature trying to understand itself, but not having enough evidence to make a conclusion.
That sounds like super inconvenient existential crisis
Sounds like a waste of time.
I am nature
Metaphysics probably doesn't exist fron what we know about physics
@@JustinL614 Metaphysics must exist because physics is finite in its explanatory ability, as the human beings which conduct physics are also finite.
What I'm saying is that metaphysics exists to provide potential answers for questions that cannot be solved by physics.
I am overwhelmed and understood only (generously)like 30% of this. That said I am also really glad someone is thinking about this and does understand it!
When I was a much younger person, I had a magic mushroom-fueled epiphany that if one was to come to understand the true nature of all 'creation' (remain calm, I'm using that word generically), everything would cease to exist. I still believe it, 40 years later.
Its a race!
The Kwisatz Haderach!
@@starrmont4981 I'm free, man!
Sounds like a fun trip
Looking forward to future videos on this topic! It's interesting how some physicists have started to become more phenomenological (if that's the right word). I feel like we're on the cusp of some great convergence.
It worries me, I think they'll just find God and then the universe as we know it will implode because man ruins everything he touches. They'll unplug the computer this simulation is running in destroy the fabric of reality.
The universe answers every question with 'yes', except when that answer would be in contradiction with any of the previous answers.
Therefore, the questions create the universe.
This isn’t true and doesn’t make sense. It just sounds like u are trying to be smart
Why wouldn't it say 'yes' even if its previous answers are contradictory? Can't two directly opposing statements both be true?
@@jackbradley4737 Yes.
What you said isn’t scientific
@@steelwasp9375 Yes.
I love how you explain Schrodinger's Cat and how ridiculous it is - I tried explaining these points a few months ago to someone and they simply couldn't understand how the thought experiment doesn't work in real life. Funny how deepening our education helps us see the world in a different light.