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- เผยแพร่เมื่อ 7 ก.พ. 2016
- First of three Messenger lectures at Cornell University delivered by Leonard Susskind
Theoretical physicist Leonard Susskind delivered the first of his three Messenger Lectures on "The Birth of the Universe and the Origin of Laws of Physics," April 28, 2014. Susskind is the Felix Bloch Professor of Theoretical Physics at Stanford University, and Director of the Stanford Institute for Theoretical Physics. - วิทยาศาสตร์และเทคโนโลยี
Video starts at 4:37.
Suskind utters "Lemme start..." at 11:38.
Thank you =)
Thanks
ALL that said, I think Leonard Susskind is the number 1 lecturer, by my book. His lecturers are "digestible" even to a novice.
He does not jump; always in good step by steps.....Good for the human specie that such a mind , as Susskind's, exists.
io non ho mi percepito il tempo che è il modo con sui si misura la DURATA come non ho mai percepito lo spazio che è il modo con cui s misura l'ESTENSIONE. Durata ed estensione sono due intensità ma non possono essere misurate con l'energia. durata ed estensione sono due forme di LUCE OPACA che " ILLUMINANO " I FATTI E GLI OGGETTI rendendoli "VISIBILI " alla percezione........ il miglior modo che abbiamo per classificare DURATA ED ESTENSIONE sono le metafore dell'ottica e lo studio della luce...
l'essere umano è un classificatore classificato dalle proprie classificazioni e come diceva Ludwing W. di ciò di cui non si può parlare si deve tacere. in ogni caso ciò che non è bizzarro dal punto di vista verbale è privo di forza rivelatrice. tutte le grandi scoperte sono tutte controintuitive.....
Undoubtedly, one the best minds of the 21st century. I don't agree with everything but I highly respect his ideas. So elegant and sophisticated.
Thankyou for supporting open mindness with two points of view. Puzzles you honor. You are so gifted.
This is a gem. Looking forward to the other three. If only all the research I did for my writing was this much fun!
What the fuck are you even talking about? I made a joke about research. I am a science writer - you don't think I think about science? And I get paid, so it is "liquid." And also, my fiction has just been nominated for a national award. Fuck off!
Pio Day - Hey buddy, we are here to enjoy a stimulating intellectual video, not to troll. She made an innocent joke and you are the unimaginative one for writing your incoherent response to an internationally published writer. You just encountered someone significant and you blew it - great job. Why don't you go to the Red Pill sites if you're going to be an ass, and leave the rest of us who have some brains to enjoy whatever is left unspoiled by idiots who have to be disrespectful all the time.
I don't think we need comments about women's sexual responses here. It may be that you are a non-native English speaker and didn't get the figure of speech, but come on, you sound like Trump in that 2005 video. Inappropriate.
Thanks for posting these, I hadn't seen them before.
THANK YOU FOR THE UPLOAD!!!!
Watch out for the change of audio settings during the Q&A. That last round of applause was heinously loud.
Thanks for the upload mrtp! I wonder then if this is a trilogy of trilogies... When the said three messenger lectures, I thought that the last three on the holographic theory, entanglement entropy etc was our lot. Delighted that Lenny is still pursuing the arrow of time question.
Bach said if the first four notes of a fugue were correct the fugue wrote itself.
And reliance on BICEP2 press release is a sour note.
Predictability and probability. When the universe decays into photons and time losses meaning. The size of the universe then as a natural cutoff regime. Double it and put the sister universe next to ours. Then rewind to current time frame and you get a big distance for a probabilistic universe over/out. You just calculated a boltzmann time bomb using the universe as a natural cutoff regime.
Particle production from quantum foam and gravitational waves and energy density regime. 😊
Black holes as finite systems. Schwartzchild for particle zoo mapping. Kerr for G-flows and hyper surfaces and quantum boundaries. 😮 ⚫️ 🐉
I like how this lecture starts with a Cartesian type of inquiry. 4:41 'Hello, am I here?'
It seems weird to me that Susskind and many physicists still argue like physicists did in Boltzmann's time. They build their intuitions with the tiniest of systems (like 8×8 coins that can be flipped), and then cavalierly apply those intuitions about "recurrence times" and "fluctuations from the norm" to the universe (like Boltzmann brains or galaxies or black holes appearing out of dust).
I nvr understood physics n probably nvr will but it is so fascinating that i still watch it nonetheless
One-way entanglement between isolated energies:
"No energy system can produce sum useful energy in excess of the total energy put into constructing it.
This universal truth applies to all energy systems.
Energy, like time, flows from past to future."
I want to get to the point where we can see other boxes, anybody working on that one?
but what about 1->2->3->1 ..., leaving out 4,5 and 6?
would that harm any physical concept?
Amazing, how did they find a Microphone to match his shirt color?
Yes, yes and yes! Is it wrong if I am not skeptical and think Lenny hit it on the nose? Incidentally I believe this guy deserves to be listened to. Coming from a guy who found this lecture too abstract to understand a year ago but now understands it much more fully.
Actually I take that back I am not skeptical, but I have not completely resolved if there really was a high level of vacuum energy when entropy was at its lowest. BICEP 2 experiments have since been nullified. Vacuum energy is low close to zero currently and it's questionable whether there is a vacuum or vacua that actually accounts for current expansion.
Incidentally, concordantly, vis a vis, etc
Created information is conserved, and information creation is conserved. This is the full meaning of the second law of thermodynamics. No microstate exists without encoded information. Even the dynamics of a volume of gas in equilibrium is a computer encoding a path through Hilbert space. The notion of low entropy states is anthropocentric, since the probability of any state class occuring is just the sum of the probabilities in that class. The recurrence time of any one state, even a “low entropy” state, is just F(# states), which is the same recurrence time for a so called “equilibrium state”.
I'm probably missing the details, but how does the low-entropy state coming from a random fluctuation disagree with observation, provided that evolution from that low-entropy state follows physical law?
Is it the because it seems much more likely that our universe evolved from elsewhere in the phase-space, rather than the low-entropy state?
I suspect that the conundrum comes from the ad-hoc combination of QM and GR used in the logic, but as I said I don't really know the details.
Regarding the arrow of time at small scale... if particles don't know the difference between forward and backward in time, wouldn't they be entangled both before and after an interaction? If they aren't, couldn't this be the reason for an arrow of time?
you had one job, Paul
Can anyone tell me if this "zone of life" and the eventual re-entry (ad infinitum?) into it is the basis for or has any relation to the conformal cyclic cosmological model as theorised and posited by Roger Penrose?
I know it's a late answer but it is related to Penrose's conjecture. The zone of life is both cases is the period where matter is close enough together to support life. Once everything spreads apart there is not enough matter to form stars and planets. Penrose thinks that in the far future all matter will be mass-less and therefore timeless. This means trillions of years are instantaneous and therefore the conditions are equal to the big bang relativity speaking. While this lecture posits space will expand so much it will cause quantum fluctuations which will cause a new big bang. Both are theoretical and without evidence but are possible outcomes so far as we can tell.
Observation shows not one but many galaxies resulting from Boltzmann's fluctuation. Why will there be only one galaxy with life, however small the probability?
The mathematics Susskind and the rest employ, is timeless and a priory in nature, enabling the Standard Model to show how fine tuning of the parameter space results in life and consciousness. More frequently, than just one galaxy with life,implying divine purpose and intelligent design.
Recurrences, or Boltzmann Fluctuations, is essentially Deja Vu.
Thanks again
Is it possible for a particle say a proton, that is moving linearly, can deviate from linear path and take angular motion, without taking a 'Pause in Motion'. Is it proton that consists of mass and energy that is in motion due to any one form of energy, stops for a fraction of time and in process lose all its energy, which either converts to more mass of that proton or that energy is given to some another mass, or that energy goes into ocean of energy that exists in vacuum and after taking an angle of some degree regain its energy back.
If all these particles in our Universe obey a rule of 'Pause in Motion' than it can conclude that time for every particles in Universe takes a pause for fraction of period. Now if two atoms {made of three different particles} are in same states than it is almost impossible to detect 'Pause Time' of one atom with help of another atom and vice versa. So any observing instrument used for this purpose also has 'Pause Time' same as the object that is observed, when both are in same states.
But when a particle accelerate towards the speed of light, the 'Pause Time' decreases. and once it reaches at a speed of light e.g. photon and neutrino the 'Pause Time' vanishes. Now for a particle moving at a speed of light, the time stops relative to the particles which are slow in motion. Keeping this in mind we come to another conclusion for time.
The more the 'Pause Time' taken by particle the fast the time runs for it and the less the 'Pause Time' taken by Particle the time runs slow for it.
4:34 If you want to skip Reverend Jim.
I understand most concepts in this video, which I find quite advanced and super interesting for a non physicist like me.
There's only this thing that I fail to grasp. Although I understand in principle that the event horizon of a black hole is in many ways similar to the cosmic horizon where things are getting away from you at the the speed of light, it seems to me there is a crucial difference between both.
We can look at a black hole as an outside observer, and 2 observers outside the black hole would agree on where the event horizon is located
The problem comes from the fact that the cosmic horizon is different in every region of space, it has different boundaries unlike a black hole. This would make a super weird scenario where quantum fluctuations at great timescales creating galaxies or black holes at the edge of the cosmic horizon would only happen for an observer located at the centre of the cosmic event horizon bubble and not anywhere else??!
What if the Universe expands forever at an accelerated rate? Then I guess the Event horizon would become shorter and shorter until the Big Rip happens and we would have a one shot universe.
I see no evidence that the cosmic horizon will stay within specified limits. I believe it will rather contract until the big rip, if the the cosmological constant expands the universe forever on an accelerated rate, or it will expand towards T=infinite if the expansion of the Universe decelerates bellow the speed of light and therefore the Hubble sphere would increase forever... This is also a way out of the box, perhaps.
It seems to me that the Universe we see which started from extremely low entropy state only requires explanation (in comparison to a galaxy created by random fluctuations) only if there is no big rip. If on the other hand the Hubble sphere expands forever are we still in a boxed Universe?
A fair bit of this has gone over my head to be honest (though I'm only a short way into the video and haven't yet heard mention of event or cosmic horizons, apologies if I'm responding a tad prematurely) so this may not address what it is your enquiry specifically concerns, but if I've grasped the general gist of it, you might consider looking into Roger Penrose's conformal cyclic cosmology theory - not to be understood as repeated expansions and contractions - which,. If correct, would allow for an infinitely linear series of "big bangs" and, consequently, successive universes.
It seems that the edge condition/function is key here! maybe they should solve the blackhole/whitehole horizon problem first to create a better understanding of entropie's influence in our universe!
When you heat the box, the entropy of air molecules confined in corner of the box will increase forward in time time through random dynamical patters. What then will happen if you cool the same box, the entropy of air molecule will start decreasing backward in time(in this case not towards initial position, but initial condition or state) through predictable dynamical patterns. In this case, there is no conflict of principles in thermodynamics, but just duality of thermodynamic principles
Nothing can go backwards in time!
@@peterdamen2161That could be wrong, tho.
@@WarmestProduct No, that's a fact!
@@peterdamen2161 I still don't think that's a fact.
@@WarmestProduct You may think that. In fact, almost all physicists agree with you. But then, I think Einstein was wrong. And more interestingly, I will prove that next year 🙂
Disclaimer:- comments are limited by space to the content of the video, and if a wider range of concepts is required for applications of principle, then it appears to conflict with the presented information, and goes against the intentions of the video. So if Physics is the science of measurement then the construction of the natural coordinates of measures requires a systematic process of building the observables into a pattern containing all the information available by implication.
Boltzman started a realization of a more complete process of inference, because extending the probability structures mathematically to other combinations of scale created a virtual reality. "The Arrow of Time " is a projected mathematical construct from the base probability of the temporal position, now. That is the limiting observation.
The laws of Newton are reversible, but first position and the final position, that has been reversed, have a different time. An increase in entropy is a consequence of there being an arrow of time. If the first state and the final state seem undistinguishable that would require an observer state. That observers own entropy would have to increase to make that observation.
Does the log in the equation of entropy tell us that there are 10 other dimensions other than the increase in entropy itself; which would be time, as the sting theory predicts of 11 dimensions in our universe
Kushik Timilsina This is a natural log, and has nothing to do with 10.
There cannot be a past. Where would the energy and matter come from to populate it? There is only the present spacetime which we can never revisit exactly.
if you dont need all particles to jump up hill again, that could explain the 70% energy we cant see but are in system.
Good lecture. Sad that the audio equipment was not adjusted well.
The dont literally freeze in the horizon right??? That’s just somehow what it looks like becauE it’s so far and seemingly unmoving????
Starts 4:34
spicy110 thanks man
Appreciate it
What if you viewed time as being created rather then all out there and the horizon of the black hole due to gravity which creates time is where it end there is nothing inside the horizon, you can't have something that exists in this universe without time, so what we're looking at is the singularity at the horizon
I have a few questions.
Is our universe one half of an ER bridge at the centre of which is the next eon?
Is our CMB the (event) horzon at the beginning of this eon in our side of a supersymetric structure?
Do we observe/experience time and the exponential expansion of our universe as we travel towards a 'conformal singularity' and gravitational centre of the ER bridge, whereupon is the photonic still point prior to the beginning of the next eon?
Could we observe mass dependent local variance (macro filament structure due to spagettification) in the over arching exponential expansion within the ERB, while still heading toward conformity at it's epicentre and the beginning of a new eon?
Are we already in one side of the conjoined wormhole or ERB?
Many thanks should you give this any of your valuable time,
Yours in faith with hope for understanding,
No.
@@schmetterling4477 well take it up with Roger cause he is running out of time!
@@Guide504 Good for you.
fantastic
Mesmerizing
When the absence of a black board "enterfears" with the latest explanation of black holes! LOL
@22:55
In other words, what Lenny is teaching is that a state of lower probility (relative to the other possible states & their probabilities) will force a 2nd state of much higher probability to happen.
Could this be the "ignition switch" behind the state of being that was, just before The Big Bang event; to transpire to a 2nd state, which was the Big Bang event, itself, unfolding?
In other words, could the probability of whatever the "state of being" was a Planck Time before the Big Bang event happened; of been so relatively low that it forced a 2nd, much higher outcome to happen, that we refer to as "The Big Bang"?
Could this concept of Entropy of triggered the Big Bang event to of happened?
I think so!
What's a chalkboard?
How to pronounce Susquehanna, sir?
Watching einsteins greatest blunder I have an idea for the expanding universe. Gravity behaves differently inside of galaxies because of the black hole in its center. Outside of galaxies, there is a natural repelling of mass away from them which in turn allows for acceleration based on how much energy each galaxy is producing with can be slower or faster depending on the galaxies around each one. Galaxies do collide but the do in a perpendicular manner which means the force of repelling a galaxy gives is on this flat plane, which causes galaxies to form as they do with the spiral effect from this black hole yet flat in nature. All of the space does not have to behave exactly the same in relation to the movement of mass with energy inside of the galaxies, then in unenergized space.
who is the man in The beginning??
In the beginning God created the heavens and the earth. Now the earth was formless and empty, darkness was over the surface of the deep, and the Spirit of God was hovering over the waters.
It's still hard for me to understand what is entropy
+Daniel Skiba Susskind does a good job explaining it in this video
th-cam.com/video/Q7Efa0mQuNQ/w-d-xo.html
starting at 18:35
in effect entropy is a way of measuring how messed up something is.
more technically speaking it's a measure of how many ways you could fuck with something without anybody ever noticing. So if something has a lot of interesting structure (like a living organism) it has low entropy. If you fuck with it, it will probably be noticeably the worse for it. eg dead.
Mess wth it enough and you'll be left with a pile of goo, which would have high entropy.
+Ralph Clark see that's the thing, why such a subjective thing exist in physics? Why does the universe care about what humans perceive as order
+Daniel Skiba it's not a human perceptual thing at all, it's a completely objective mathematical thing.
entropy S=log(N)
where N is the number of ways a collection of states could be rearranged without actually changing anything that could be detected or measured.
But as you can see, although it is completely objective and is fundamental to macroscopic physics, it's underpinnings are purely statistical, and don't depend on any particular physics themselves.
Since they are purely mathematical, the laws of thermodynamics are therefore thought to be fundamental to any and every universe.
+Ralph Clark I see now I look at it differently when I look at the equation, you see it always bugged me when people said entropy is the amount of disorder in a system, because disorder is a subjective view, one alien race might see a pile of goo as perfectly ordered and they would have a harder time finding s=log(n), anyway since entropy equation is what it is, is it 100% correct to claim entropy is the amount of energy in a system unable to do work? The higher the entropy in a system, the lower work can be done with the same amount of energy, is this a correct interpretation?
Nothing much interesting may happen at the middle of the ring. Maybe one occasional galaxy.
But at the rim of the ring could be a high action place with usual multiple galaxies. So nothing abnormal at the rim of the black hole ring.
Zeno k-now kelvin scale Caltech k-new continuous fractions k-11letter [k] kilo glass blower looks like zeno~!
Actually starts at 1130 about.
So we're just going to ignore that princess Lea is introducing susskind?
56:43
@mrtp
THANK YOU FOR THE UPLOAD!
Please read my comments & critique them. Point out my misunderstandings. This is how I learn the truth.
Please & Thank You, in advance.
55:40
53:33
Excellent talk. It’s also an honor to see someone with Paul’s credibility rocking the “Bozo”. With zero cares given, he owns that hairstyle!! Bravo Paul, bravo.
I think it's pretentious. Doesn't take but 5 minutes to fix one's hair. There's no excuse for going before large audience looking like that. It's actually disrespectful to everyone around you to be this disheveled
what is the basics in this field ??
Piter DeVries
Time flows, because cause comes before effect in every Einsteinian time line no matter what the reference frames are and what gamma factors are in play. It is ALWAYS cause before effect. Hence time was born. Why is it not reversable, because effect cannot come before cause. What Bolzmann was trying to do, was to find a deeper meaning to it by distinguishing between aspects of cause differing from aspects of effect. I still think entropy increasing is a statistical phenomena. Not a physical phenomena (very strictly speaking). Entropy increases because it is statistically the almost the only way an effect follows a cause. It is just the same as with evolution. The earth was not made for life, it caused life and the life it has now, as at the moment the best adapted to this planet.
Isaac Newton walks 10 across the room......
at the same time , Newton's brain's neuron "walks" across Newton's brain billions of step...
One day, we may be able to see a Static Universe....as in a Planck time's Universe, where nothing flows....
Then, we would then ask, " If nothing flows , WHO ARE WE?"
Of it's absurd....if nothing flows, so does NOT our neurons...and we could not ask that questions....
Entropy always increases ...except for crystals, galaxies and Black Holes of course.
You are considering subsystems. The entropy of a subsystem can diminish but entropy overall will still increase. This distinction has been understood for a long, long time now.
9:10 Blackboard
if time was flowing backwards once in a while we wouldnt know either as everything would go backwards including our memory and experiences.
You just blew my mind.
Not even our tests and equipment could detect it if it was universal. However, time flows in reference frames, so those would be out of wack and detectable unless corrections were made up offset the backwards flow. Additionally, I think the spatial dimensions and illusory force of gravity would be deformed/affected by the energy required to decelerate/accelerate time.
Maybe time is flowing backwards and we've been looking at it wrong the entire time.
@@Hexnilium causality goes both ways, one of them increases entropy and we call it forward.
Probability is not a force, it's a way of describing things that have a force acting on them. I don't think that there's any probability that gas molecules would ever end up on one side of a box because there are other forces acting on the molecules to prevent this, such as Brownian motion.
If those were mice instead of atoms the no entropy picture would make sense
Suskind asks but not answers the question "So... how it happened that we started with extremely low entropy universe?" What not really seem possible to happen by his lecture. I assume his arguments and also on whose it depends on are wrong. So if we had once => there will have others too. I can guarantee that (what Suskind can't) ;-))
Where can I read your paper?
We HUMANS are physical ( wave-function) forms. Our internal organs used to be bits of other "outside" chemical processed cells that "entered"
our body with symbiotic functions to form this UNITED OUTWARD FRONT OF OUR PHYSICAL SELVES.
With this self, our brains think and is curious of our world, especially, the part we can DETECT with our senses and instruments.
The Cosmos, seen or unseen, is always BIGGER THAN US, by far....
We will discover more....But we forget to ask, what's the point of being alive and discovering more, even for more advanced aliens from other planets?
Others will dismiss this as "defeatist" thought....I know...Survival of the fittest.....The fittest is the end result...If you didn't survival, you could not ask
this question "WHY SURVIVE?"....
About that equilibrium universe picture, when there is nothing but stuff on the edges, what is the center? Can you just pick some point in the empty space, call it the center and describe everything as relative to it for the billions of years? I don't think so, and it makes the whole argument misleading, because it is based on a false assumption.
And look at 52:38. The human is not in the center of the universe, so his horizon would surely differ from the horizon relative to the previously chosen "center". Looks like pseudoscience to me.
The second law has now been demonstrably broken. @
The whole area bears reexamination. Please watch and critique this simple experiment.
You sure that second law can be broken?
@@filipvasilevski8115 I am sure that I can get a small amount of electrical power form ambient temperature by using a tower full of air, a thermoelectric generator, and gravity (plus a lot of insulation and copper). th-cam.com/video/CXP5jy_XlIs/w-d-xo.html
i could remember all of those flip combinations easily but i still remember very number in my ex wifes old wallet from 14 years ago so i might be a weirdo
sorry, but there is certainly misunderstanding of what life really is when Susskind is considering a diagram of a phase space of the universe including some small region, compatible with life. this view on the life is absolutely wrong. life evolution is a specific deterministic process driven by the same fundamental laws of nature as how we describe the cosmological evolution of matter in the universe. the laws of physics underlie all of Darwinian evolution
we can consider the planetary life as a preprogrammed event starting from the very moment of the birth of the universe with the very special conditions (which we can tie with the anthropic principle). life is inevitable for the universe with physical constants and the laws we have in the observable universe. time for the evolution of life is really finite, but this is another story which should be investigated theoretically with the help of new cosmological models relying on the theory of everything.
There are no perfect symmetries, there is no pure randomness. the mechanics are not random, they're fractal. Think of a tree growing in a box with the inside surface of the box as the place where we will register the probability of the tree eventually touching after growing for a period of time. Roughly speaking any portion of the surface has an equal chance of the tree touching it but only some portion of the surface will ever include the tree. Now replace the box with an onion type, container, where each cycle of time includes both a portion of growth for the tree and another layer for the onion. the inside surface of this onion now includes a new probability distribution where each new layer is dependent on the previous layer and each new layer you has a finer resolution with more degrees of freedom but not infinite degrees of freedom. The center of this structure had few degrees of freedom and the final layer has the most degrees of freedom. The outer layer of the onion would not be a perfect sphere, it would be more like a fractal surface such that the surface area would increase with the resolution. Our universe, the universe we can see is the tree like structure.
متعة خالصة لمحبي الفيزياء النظرية
You need the Higgs field to be in this universe so the field end at the horizon
arrow of time hahahahaha
Three question at around 54 was right on the mark. Time is how consciousness (mind) perceives it as change in memory. Materialists insist, without any evidence, that it is has to be physical . It is pathetic.
no blame to the hon. speaker but speech intelligibility is very poor due to the acoustic the venue room needs acoustic treatment badly
he has giant ears
As will you, one day.
All the better to ear you with.
When you graduate, you become a PhB? LOL
Wow. When you see the guy who introduces Leonard, you know that he is either a genius or lives in his uncle's shed building bombs.
Right because people who look unlike you are either brilliant or suspect. What a wonderful world you live in!
It's the former.
Quantum physics is wrong. Particles and waves, sure!
How did that work out in school for you? ;-)
Nothing is random.....please.
Would not like to be one of his students
ngl this man is kinda sus
Yes, but he's kind.
I dont agree, Im about to publish my theory. All this is nonsense.
what theory?
jamesmasonic lol
Physics is so boring lol
Susskind bores me .
56:20
56:30