The woo explained! Quantum physics simplified. consciousness, observation, free will
ฝัง
- เผยแพร่เมื่อ 15 มิ.ย. 2024
- Signup for your FREE trial to The Great Courses Plus here: ow.ly/ilR330pHoFu
Quantum physics simplified. Are Consciousness and Free Will linked to quantum mechanics? The double slit experiment explained. What is the difference between observation and measurement? Since Quantum Mechanics is the basis of all modern microelectronics it is extremely important for you to be able to separate quantum mechanics facts from fiction.
There are misconceptions about quantum mechanics. I explain as simply as possible how quantum mechanics actually works. In 1801, British physicist Thomas Young performed a double slit experiment which showed that light was a wave, because it formed an interference pattern as a wave would. So for most of the 19th century light was considered a wave.
However, in 1887, German Physicist Heinrich Hertz discovered the photoelectric effect. This is where light can knock off electrons from atoms. But this was not triggered by certain colors regardless of the intensity, but only by higher frequencies of light. This was not the way a classical wave was supposed to behave.
This mystery was solved by Albert Einstein who proposed that light was not a wave, but came in packets of energy, photons. And the energy of these particles was proportional to its frequency of the wave. So Young and Einstein’s results seemed to be in conflict. Was light a wave or a particle?
In 1909, G. I. Taylor performed a double slit experiment such that only one photon was emitted through the double slits at a time. He showed that individual photons look like particles, but a bunch of photons behave together like a wave. This experiment was later performed with electrons which also showed the same pattern.
But people were perplexed as to what a wave of an electron actually means. In classical mechanics, Newton’s second law makes a mathematical prediction about the path a physical object will take, if you know its initial conditions. Something that showed a similar mathematical description of the wave of electrons was needed. In 1925, Austrian Physicist, Erwin Schrodinger, invented such an equation that revealed the shape of this wave function. Unlike Newton’s equation, it is not deterministic. It evolves over time. The Psi in the equation, which looks like a trident, is a wave function. In 1926, German physicist, Max Born, worked out that the psi function was related to probability.
The most accepted interpretation of the wave function, called the Copenhagen interpretation, says that until a measurement is made, this equation tells us that the electron is in all the potential positions at once. So when the measurement takes place, that’s when we say that its wave function has collapsed, because only at that point can we ascertain where where electron is or what its properties are.
And this collapse of the wave function is where the main confusion occurs in quantum mechanics. There is no equation that outlines exactly how this collapse occurs after measurement. This has been called the measurement problem of quantum mechanics.
I’ve been careful to use the word measurement instead of “observation” - which many textbooks and physicists use interchangeably. But observation in quantum mechanics does not require eyes. It is simply a measurement. So what is a measurement? When an electron bounces off an atom, that’s a measurement. An observation in physics does not mean a conscious observer. Just about anything can be an observation. If an atom in superposition interacts bumps into another atom, that’s an observation.
In the double slit experiment, when a single photon hits the screen, it collapses the probability wave of the photon. It shows up as a particle. That same photon is acting as a wave prior to hitting the screen, because it hasn’t been measured yet. The screen measures it. If enough photons are fired, you get a distribution exactly as predicted by the wave function.
The measurement made was a purely physical measurement. It would not matter if anyone or any animal looked at the measurement. Overall what we can see is that the fundamental underpinnings of nature are probabilistic not deterministic.
Does this justify free will? No. Just because free will implies that your decisions are not deterministic, and quantum mechanics implies that the properties of small particles are also not deterministic, the two are not related. There is no science linking the two.
#quantumphysics
And consciousness is not required to collapse of the wave function. The universe exists whether we are here to observe it or not.
The Great Courses Plus is currently available to watch through a web browser to almost anyone in the world and optimized for the US, UK, and Australian markets. The Great Courses Plus is currently working to both optimize the product globally and accept credit card payments globally. - วิทยาศาสตร์และเทคโนโลยี
![Fc ครับ ขอแนะนำให้รู้จักกับ "น้องเปียโน" l [Nickynachat]](http://i.ytimg.com/vi/HQU6Q_IYTLo/mqdefault.jpg)
This video reduces my confusion of quantum physic by 20%
mine was raised by 20% :)
Watch it five times 😎😎
Too good % reduction considering the video time of only 13 minutes.
Your confusion could have been reduced anywhere between 0-100%, but you had to go ahead and measure it.
Currently my state of confusion is still in superposition.
One of my first questions upon studying Quantum Physics was this, "What exactly do they mean by "observe"? This video does a wonderful job of answering that question! Thanks!
But how do you detect a photon?
I was wondering exactly the same. The truth doesn't inspire an DMT-fueled all-nighter discussion the same way as if consciousness was involved, does it. 😄 #mildlydisappointedtho
@@amitaimedan with a photon detector obviously
...sorry to disappoint you Mr. Sandlund-this video is not only far away to "answer" your Q but presented attempt is very simplified and incorrect...
...but hey if you get it good for you...
...all the best...
8:52 this is where he make a mistake. interaction between particle didnt make wave function collapse. it will make both particle become entangled. we can measure again with another particle but it also will entangled with previous particle.
no one could prove that if we shot a particle with particle, make them interact, will make wave function collapse if there is no presence of observer (concious mind). How you can tell that wave function is collapse if you are not there interpreting the measurement result?
this is the real measurement problem. and this is also the root of "consciousness collapsing wave function" theory.
this explanation in the video didnt explain much. it will only make people think that consciousness is not necessary for collapsing the wave function. in which not true. there is a scientific experiment that prove that consciousness actually effect reality
what arvin ash point out in this video (also almost all of his video) is to bring the personal agenda, that was The Materialism.
Schrodinger arrives at the vets to pick up his cat. The vet says, "Well, Mr. Schrodinger, I've got some good news and some bad news..."
Well,they both are just news until the vet says the 1st news to schördinger.
Mr. Schrodinger -> Dr. Schrödinger
The good news is that your cat is alive. The bad news is that your cat is dead.
@sim sim salabim actually, the conversation could, or will, or would (your choice depending on your quantum state) go like this:
"Dr. Schrodinger, I potentially have some bad news or I potentially have some good news: your cat could possibly be dead or you cat could possibly be alive."
@thejils1669 no, the thought experiment was meant to show how absurd the Copenhagen interpretation is by telling you the cat is at a state of being both dead and alive UNTIL you open the box, not potentially.
I can't say I understand everything, but I'm still binge watching
perhaps its already colapsed because of the spliter...and because of the spliter it blocked other photon and because of the spliter othe photons blockes.only those photon entered the spliter reached the screen.
It was all fun and games until Schördinger's cat started living and dying, and living and dying at the same time.
I didn't get into that, but the cat was used by Schrodinger to show the absurdity of the interpretation of his own wave equation. That is not the way QM would actually work for a cat.
Arvin Ash: thank you. I've thought that same thing--NOT the way it would work for a cat, but so often people get angry when I mention that.
@@jilliansmith7123 There's a famous saying by Mark Twain, "Never argue with a fool, onlookers may not be able to tell who the fool is."
@@ArvinAsh "That is not the way QM would actually work for a cat." Except that IS the way QM seems to work for a human consciously not observing a cat. Yes, Schrödinger was absolutely pointing to the absurdity of the logical consequence of his equation under the Copenhagen interpretation. Again, please avoid presenting these beliefs as though they are fact. We just don't know, and the darn problem is so immune to investigation. And again, I hold the same belief as you. Maybe the truth of the cat not actually being both alive and dead lies on some Gödelian true-but-unprovable island. I hope not.
@@Juttutin Not sure what your argument is. I am not stating a belief. The cat as described by Schrodinger is NOT in superposition like subatomic particles are theorized to be. The cat is alive OR dead, not alive AND dead.
I wish this guy was one of my teachers in high school. Hell I wish I could just sit down and ask him questions and have conversations about this stuff, I think about it all day
Do your self a favour and don't take everything this guy says as truth. He doesn't understand quantum mechanics.
I rather take his word then some random in the comment section.
Its not even his theories.
Its just him interpreting and explaining other peoples theories.
Which you would understand if you werent trying to drag him through the mud.
At least have a damn argument.
Arvin does a fantastic job explaining these theories. Whether hes right or wrong is not even the point.
Hell, i disagree with him all the time on things yet that doesnt make him wrong or bad.
He's still a great source of info and explanation.
@@desperado3236 I think he's good too, just not quantum physics though. There is no explanation for the cause of the collapse that takes away consciesness from the equation. Whomever comes out with one would get the Nobel price.
@@GJ-dj4jx quantum physicists are drug addicts like you. How the hell you would know if you don't look at it
Your optics diagram grossly wrong
Square pyramid, refraction etc
philipbradfield2@gmail.com
Mr Ash is the physics teacher I wish I had. To explain something so complex in such a simple and understandable way is truly an art.
Thanks my friend. I really appreciate it.
Indeed! It is an art.
@@ArvinAsh th-cam.com/video/zy6mVAb-UjU/w-d-xo.html Hard to deal with it, isnt it ? 😃
Well said, Thomas! And really well done on an extremely strange, complex subject, Arvin. Thanks!
Finally, an answer to the age-old question: If a particle interacts in a forest, but nobody's around to observe it, does its probability field collapse?
Haha. I made a dedicated video on that age old question. Check it out.
@@Takeitinnblood Great point, and one that I think this video did a poor job (in fact no job at all) of covering. Nevertheless, I appreciate the knowledge you share, Arvin.
Only if a bear pooped on it
Read "Life on the Edge" 2016 by JohnJoe McFadden - award winning science book on quantum biology
@@ArvinAsh why a photon or an electron's wave function doesn't collide when it is shot from the instrument to the screen through the slit? by the definition of measurement in quantum world it was measured when it was in the atom, when it was shot, and all the time sub atomic particles were measuring it.🙄
I have been investigating these topics for many years and have NEVER heard a more clear and concise clarification of these fundamental questions! Nicely done.
I've been recommending searching for double slit delayed choice quantum eraser. The vid is great and concise but it is missing a part of the experiment which is worth looking into
@@EminorReal th-cam.com/video/0ui9ovrQuKE/w-d-xo.html Here's the video
Like the way you made it clear on the difference between Observation and Measurement.
It was interesting considering they've been hundreds of experiments showing that a measurement buy a computer does not collapse the function or change it but a conscious observation does the best analogy for why that's not discussed is when they ask scientist to look at their results they say ( I don't want to)
@@mccullum2593
I've not heard of one. It's mere interaction with certain macro phenomena that causes the wave function ro collapse. It's why quantum computing is so difficult. Inagin trying to isolate qbits from all outside interference.
Biggsy DaBoss, you haven’t heard of one because that fact invalidates materialism, and scientists that rely on publishing papers can’t risk running afoul of materialist dogma or else lose their funding.
Consider doing your own research rather than taking the word of someone with a vested interest at face value.
As a thought experiment, try to find an example of an experiment where they still measured without looking at the data and found that the wave function did collapse.
@@mccullum2593 where?
@@Acsion42 as a thought experiment, post these supposed experiments that show consciousness being involed in QM observation is anything more than taking the wrong definition of the word
You talk very relaxed, thats why its very easy to grasp the tiny bit information coming from you.
Thanks man for sharing the knowledges
I just today found your channel and have been sucked in to your elegant way of making confusing subjects understandable. Although I felt like I understood most of the subjects, your explanation furthers my confidence in my understanding. Keep up the amazing work. We need more minds like yours teaching our children.
One of the best explanations of quantum mechanics I have observed.
Or measured?
Best explanation of the wave collapse and the definition of what is an observer. Can't tell you how many hours I spent to figure it out; if only you were around earlier...
Ash. So glad to see that your sub numbers are up. I wait every week for your new video.
Thank you so much.
The delayed-choice quantum eraser experiment completely contradicts the assertions in this video about what observation means. It is not physical interaction. The electrons in this experiment travel along mirrors and prisms, and the paths that reveal logically the which-way path show particle behavior, and tha paths that do not reveal logically the which-way path show wave behavior, even backwards in time.
Best description of double slit I've heard. The graphics are great too. Really glad I watched, thank you Arvin Ash
Best part: the articulation of measurement VS observation. Great work! 👏 👏 👏
Hardly.
The measurement problem has not been explained as even this TH-camr says.
Just because Consciousness isn't required which is a claim not a fact doesn't mean Consciousness doesn't collapse wave functions.
Thank you so much.. word "observation"always made me think that its some kind of magic and it can not be real physics..but it all makes complete sense when we use correct term "measurement"
An even better word would perhaps be "interaction". Collapse of "wave of probability" is caused by interaction with another system. Like photon hitting a slit.
I like how tyson descriped it, he said something that meant quantum world is so small that taking information out of it is already too much.
Measurement implies fancy instruments and conscious intent. I'd agree that "interaction" - even if inaccurate - is a better way to distill this concept.
Green Kizuen Wow that’s a really good way of putting it
@@MrRaizada Yes but the slit does not collapse the wave function, yet the photon clearly interacts with it. How can one interaction collapse the wave function, but the other does not? Interaction doesn't seem to be the right term here.
It's astounding how much clearer this is for me now, I was beginning to think there may be some hurdles just to high. I am going over to another link to work on my writing and spelling...I'm feeling confident now.
Thanks Arvin for taking the time to explain this. Much Appreciated.
Jon
Far and away the best science content I have ever watched. Well done sir.
Thank you Arvin
At last a brilliant and precise description of a complex subject.
Amazing ! You actually explained the double split paradox with an explanation that makes sense.
And excluding the conscious observer clears out A LOT of misunderstanding.
I’ve been watching your videos for quite a while. This video is exceptional. Many thanks Arvin for clearing up my understanding of observation with QM
The observation always confused me because how can an electron know when I’m looking but you helped clarify this
Though the vid being very informative and helpful, it is missing a look into double slit delayed choice quantum eraser, which in my opinion is worth checking out
Thanks for taking the time to research and dispel these misunderstandings. In my opinion, the reality of quantum mechanics is much more profound than any of the misconceptions make it out to be!
Best video ever explaining the double slit experiment and it’s interpretation 👏🏻
this video is awesome, it is like this was made to solve my main questions about this particular topic of quantum physics, I love it. Thank you.
New to learning quantum things and am increasingly interested in learning the rest of this topic. Very good video. Subbed
Amazingly and clearly presented to lay people. You're an extremely good explainer.
Thanks, that really clears things up! Glad I watched this video.
....wow...again!..... Spent countless hours trying to get my head around this stuff and BANG! you managed to explain this so well I think I now understand! Thankyou Arvin, thank you so much.
I’ve watched a bunch of videos regarding quantum mechanics, I feel like this dude has explained it the best, especially the description of measurement vs observation made it much more clear to me
Glad you found it helpful...dude.
Keeping it sweet and simple. Amazing work!
I love your videos Arvin. My interest in science, space and topics that i never thought i could grasp have grown exponentially since following your channel. Cant wait till the next one
This was an excellent video and superbly narrated. Really well done!!!!
You are born to deliver this complicated content. So smooth. Ty!
"I regard consciousness as fundamental. I regard matter as derivative from consciousness. We cannot get behind consciousness. Everything that we talk about, everything that we regard as existing, postulates consciousness."
- Max Planck
"Consciousness cannot be accounted for in physical terms. For consciousness is absolutely fundamental. It cannot be accounted for in terms of anything else."
- Erwin Schrödinger
Both of them have got a lot of things wrong. Same with this. Consciousness is nothing special. Measurement is not made by a conscious observer. It is just an interaction between a measuring device or a photon interacting with the system. Enough with the bullshit pseudoscience.
Smart people can be wrong too you know.
@@Jopie65 True. But I think it speaks to the fact that scientists themselves are divided unlike the black and white picture portrayed in this video.
@@clawfinger
Maybe they used to, but when quantum mechanics became an established theory, there were not many scientists who concluded that quantum mechanics is an effect of consciousness.
Nowadays, the argument most people have for that boils down to 'quantum mechanics is mysterious, consciousness is mysterious, so the two are probably linked somehow'.
@spaghetti yummy Sometimes I eat so much that I feel like I'm spread out everywhere.
Really Thankful to Arvin ! It literally reduced my confusion in Quantum Mechanics a bit . And , I think my confusion of Sir G I Taylor's experiment is solved . Btw , to me Arvin Ash is the best explainer in Science Ed .
You know its a well delivered lesson when it makes perfect sense but you have no clue why!! Thank you
this is the best rundown of quantum mechanics i've ever seen! thank you Arvin
Another fantastic video, thanks Arvin!
That was really great and answered a lot of my questions about "observation" thank you!
Agree
Arvin Ash. I think this is one of the best videos you have put out
Really helpful with the measurement problem.
Dispelled for me a lot of the confusion over measurement and observations.
Consciousness and non conscious
Nice one !Thanks
Love your videos, Arvin! Keep 'em coming!
Thanks so much for this video. Finally, this makes sense to me.
I wished you were there when i was in school, 14 years ago, probably i could had become one those deep thinkers. Thank you for your passion. You have a permanent subscriber.
Nice! Thanks my friend.
I think you have had explained the confusion between abservation and measurement very well but beyond well. Using measurement instead of abservation really Changed the entire conversation about the abserver.
Clearest explanation yet! I finally understand this basic problem.
Thank you. I finally get some common sense and clear explanation of this consciousness matter which didn’t really convince me.
The world needs more of this
You did an excellent job explaining quantum in the ten minute time goal you set. Of course, there's a lot more to this subject matter, but you did a great job.
you deserve so many more subs dude... your videos are awesome. thank you so much!
As anybody else in the world you have your detractors but for me you're one of the best educators on TH-cam.
Thanks Arvin.
Very lucid decription of the Copenhagen interpretation. There are alternatives to that. "Many Worlds" and "Pilot Wave" offer different ideas on the wave function. Since this was so well done, I'd love to see your video on those. But understanding the Copenhagen interpretation is good enough for most people to begin to grasp the concepts behind QM and be able to move on to all the strange things that it implies. I've studied this for 25 years and it still is hard to grasp.
One of the best explained videos I've seen. Than you!
Maaaaaaan this video helped me understand better some of my most perplexing questions about this topic. Amazing!!!
Finally someone explain observation to me.. Thank you 😃😃
Arvin, another precious one 👌
Thank you Arvin. Another outstandingly great video. Thank you for clearing up some misunderstandings about quantum physics.
It seems that Quantum physics is the reason there is chance and why there are variables in life. I agree it has nothing to do with consciousness and that the physical universe will be here whether we are or not. Thank you very much! 👍
I like you, i cant find any interesting facts whilst i watch that you dont suddenly make comments about. also, ""These are packets of waves" he said" is a nice way of making a statement your own (at first) but then turning it into a quoted reference for credability; i liked how you did that. ive subscribed. good work!
That was so enlightening! You dispelled the most common misconception that light behaves differently when it is observed. That was worth my precious time and it's no misconception that time is precious.
rwarren58 Unfortunately the delayed choice quantum eraser experiment was not discussed which shutters the notion that an observe or consciousness is not required to collapse the wave function.
@@OSFSCANNER no it doesnt. How? Like, how in the slightest? It deals with whether which-way information is retained. Not the same thing.
@@jorgepeterbarton umm... yes, I'm afraid it does.
@lasest2 I believed it until this video. It went right to the nature of reality and the concept that the universe is a living thing. The latter may or may not be true but at least one truth as been revealed.
Thanks for explaining "observation". It was always hard to understand.
What a clarifying explaination.. Mind-blowing and fantastic!!
Today I learned what it really means by observation in physics. Thanks Arvin. Keep it up.
I am confused about the fact that, how he generated a single photon?
Same here.
There are lots of ways now. I think at that time he did it by generation like 1000s and 1000s of protons and sending them inside a box where they bounce of the walls and get absorbed. But every few seconds a photon pass through a pin hole. Now you just need to turn off or block photons after first photon pass through. And you have single photon.
@@lalit5408 So does this mean you are/were observing or measuring that very photon - which leaves the photon source - already once before it reaches the double slit and later on hit the screen?
I doubt the way we were told how the experiment really works and what influences the behavior of those photons. Perhaps there are more effects to take into consideration than we imagine to understand the results/patterns on the screen.
George Blau I’m a curious mechanic and I’ve always wondered the engineering on a “single” photon or electron. I bet it’s just like a bundle of water molecules making a wave, it’s a bundle of photons and electrons that the experimentalists don’t care to mention due to funding blah blah blah.
You can do it by decreasing intensity of light until it shows the intensity is minimum which marks a single photon.
This produced a huge leap in my understanding. Thanks.
Well to the first one i would like to know that too. So basically any interaction of the photon would be a measurement and collapse it's wave? Maybe you can elaborate on that a bit. Thx
@@darkfireeye Personally, my misunderstanding was "How can we know that 'observation changes the state without first knowing the state'". Now I see that they are two distinct things. IF I have this right, the particle does not actually exist except as a wave of probability until it interacts with something else.
Arvin, thanks so much for doing these. Very interesting.
Excellent. I always had question of measurement. You cleared it really well and it’s easy to understanding.
The delayed-choice quantum eraser experiment completely contradicts the assertions in this video about what observation means. It is not physical interaction. The electrons in this experiment travel along mirrors and prisms, and the paths that reveal logically the which-way path show particle behavior, and tha paths that do not reveal logically the which-way path show wave behavior, even backwards in time.
Wow, what a great video clearing up some major misconceptions that people attribute to quantum mechanics. Please make more like these! For instance, showing that the Copenhagen interpretation is only ONE of other possible interpretations. I think you did an excellent job choosing your vocabulary and metaphors. Great job!
Super informative, thank you.
Thank you. I finally (kinda) get it! The measurement explanation helped immensely!
Thank you so much. Your explanation about the meaning of the basic quantum equation has been the best ever heard.
I appreciate you making the distinction between observation and measurement; I feel that is often the stumbling block when discussing quantum mechanics, since observation implies a living conscious. Great explanations, thank you!
Thanks. Yes, the word "observation" is very problematic.
Thanks Arvin. I am enjoying your exploration. Perhaps there is a different interpretation of the reason the double slit experiment changes. You mentioned that there doesn't need to be a conscious observer and it is really just measurement that collapses the potentiality wave. What if we remove the identification with ourselves, thinking we are a separate special bit of consciousness and see the fundamental nature of everything as the same consciousness. Then consciousness would be just interacting with itself in measurement or observation and collapsing the potentiality into a new expression of life/matter, consciousness in the form of life constantly blossoming itself. It doesn't need a special bit of identifiable consciousness called a human or even an animal to affect it. We as human expressions of consciousness just have the beautiful capacity to be aware of our awareness and thoughts, which gives us a sense of separate importance, and ultimately the doer somehow responsible for what we perceive. Perhaps we are fundamentally the same consciousness as is the fabric of the materially known and potential universe. This just takes it back to everything as potentiality until consciousness interacts and it collapses into matter and removes the illusory subject object causal definition.
Arvin, You simply are “A GREAT TEACHER”.
Thank you Arvin! This video helped me fill a little more comfortable with my small universe.
Decent video Arvin! The 'observation vs measurement' distinction was enlightening. Now please go down the quantum eraser rabbit hole, where the 'measurement' is made well after the photon/electron/atom/buckyball/etc has passed through the double-slit, but yet the wave function behaves as though it was collapsed before the particle (or in the case of buckyballs, even a somewhat largish molecule) has even passed through the double-slit. Does the measurement somehow reach backwards through time to collapse the wave function? Thanks for your great work on this subject!
Yes, that is a rabbit hole indeed. As I said in that video, I don't understand it. It is known that entangled particles share the same probability wave, so I have no issue with collapse occurring simultaneously. The wave, apparently, is shared in both space and time. Exactly how this happens is a mystery to me. I am hopeful that some new insight or equation will solve this riddle.
I'm going to make a playlist of my favorite Arvin Ash videos.
Please do. Thank you.
thankyou for clearing up "observation".
i've always sensed that this was a vague definition, misleading, and would ask about a precise definition, but everyone seemed to not give satisfactory answers and didn't care.
you're a great teacher.
Observation is irreversible energy transfer. Five words are enough. You don't need an entire video for this triviality. If nobody has been able to explain this to you, then you have always been talking to the wrong people. ;-)
Thank you so much for the clear and concise explanation of the double slit experiment. The confusion with the "observer" effect is now gone. Since quantum mechanics began with this experiment I would love to see a video explaining it and all of its variations in its entire evolution (from the original to the delayed choice quantum eraser, etc) to have an overall understanding of the quantum world. Thanks in advance!
Quantum mechanics began with Planck's formula for black body radiation. It was then followed by Einstein's explanation of the photoelectric effect. The double slit did not play any role in the development of quantum mechanics whatsoever. It's not even a quantum mechanical experiment. It's pure wave optics and it was in 1801 that Young explained his observations with a scalar wave theory of light. It would take another 125 years before QM as we know it would be fully developed.
The double slit bullshit seems to come from Feynman's really crappy undergrad textbooks. :-)
Hi Arvin. When you said an electron bouncing off an atom is a measurement (8:36), did you specifically use an electron as an example there or would it be the same for a photon?
P.S. Love all your videos! Been binge watching them since I found your channel.
The reason I used the example of the electron is because it can be measured without destroying it. Photons or their energy can often be absorbed by materials.
One of the best explanations ever
thank you so much for making a complicated subject enough simple and clear for people like me.
Using the word measurement instead of observing is a very important idea to talk about, thank you soooo much.
Best explanation ever 💓💓
I have a question about collapsing wave function. If a photon has been measured, is the fact that its wave function has been collapsed, stays as a property of this particular photon? And the photon carries this property with it? It's how I understood your example at 10:03 of the video. Does it mean that some photons have their wave functions collapsed, and others - not? And the photons "know" about their wave function state? Now the main question: does this mean that if a photon that came to use from the deep space has interacted with something during its journey through the space, and its wave function has been measured, it will stay measured forever, and if we manage to get a bunch of the photons measured this way, we will have the two lines in the test even though it wasn't us who measured it?
Also, an additional question: what if we manage do measure all photons in the test with different detector, will it show two lines or many lines? I just though, what if all those photons with collapsed wave function that show two lines as particles, are actually united in a system because they have been measured by the same detector? And if it was different detectors, the photons would have been measured but still acted as a wave, because they are not a part of the same quantum-interacted family anymore?
No. There are no photons with collapsed wavefunctions flying around. That would be very weird! It is the problem with the Coppenhagen interpretation, which is a very old view, and considers this collapse to happen. No such collapse happens, it only seems that way from our perspective.
@@pszotter Then it's strange that when photons in double slit experiment are being observed, they switch interference picture to "particle dispersion" one. How to explain this if there's no wave function collapse stored in photons?
It is called dehocerence. The propapilistic nature of the photon, electron, or other particle dissapears for thos objects (observers) that interact with it, meaning they get information about which slit it passes through. But the wavefunction does not collapse it is just expressed in terms of different bases. And you cannot treat the particle separately, you also have to consider the states of the observer. Either: |observer not knowing which slit observing interference pattern> and 1/root2|photon left> + 1/root2 * |photon right> two independent parts of the universal wavefunction
Or: 1/root2 |observer seeing photon left> * |photon left> + 1/root2 * |observer seeing photon right> * |photon right> decoherence because observer received information about particle or photon, but can only observe one possibility at a time. The other possibility is also real, therefore no collapse.
pszotter how do we know we are sending one photon? I doubt we know enough about that
@@redneckrevolt1 Search for single photon light source. One atom getting excited then de-excited, one photon is emitted.
I've watched videos and read about the particle/wave duality in a few places, but your video was the one where it clicked on my head. Thanks!
Thanks. Glad it helped!
A Brilliantly understandable video of a highly misunderstood topic. Bravo! Subbed.
I’m always leery when humans talk about these things, I feel like it’s monkeys discussing how Chevy V8s are designed.
The understanding of physics is entirely based in mathematics. So it’s not say a field like biology (no shade) where there is more just knowing a fundamental process, everything is explained fundamentally with math.
@@CraigCsintalan biology, my friend, is physiology. Cut an animal into pieces and you can actually SEE the parts. Your point doesn't hold, or even compare. (No shade ... really.)
Why are you skeptical? If ALL math in the Standard Model were wrong, you wouldn't be watching TH-cam and replying to this video.
How do we (humans) know how to do that, then?
"The understanding of physics is entirely based in mathematics." It is true and that is what is wrong with physics today. Too much mathematics and too little physics. That is why physics today is so speculative and should not be trusted.
Aleksandar Ignjatovic bruh . BRUH WTF.
Great video. Also be ready for the Delayed-Choice-Quantum-Eraser-Experiment because people are going to say measurement is not necessary to collapses the wavefunction. but in this experiment is also Not necessary a Conscious Observer to collapse the wavefunction. What really collapses the wavefunction is the AVAILABILITY of the which-way path information and It doesn't matter if this which-way path information is stored in an atom and no one observes it. It still does Not require a Conscious Observer to collapse the wavefunction, just the availability of the which-way information recorded in some medium.
Exactly, some people still use this experiment as a proof for a Conscious Observer to collapse the wavefunction when this is not the case at all in the DCQE
Yes, excellent summary! Thank you.
As I understand, in the DCQE-experiment, the choice to measure or not is made -after- the electron has already gone through the double slit. And depending on whether the choice was "measure" or "not-measure", the electron's wave function will turn out to have collapsed when it went through the slit (or not).
Essentially, the making of the measurement determines, retroactively, that the wave function collapsed at the time it went through the double slit (or not). That seems consistent with the idea that a measurement is needed to collapse the wave function -- all it changes is that it is not required that the measurement to be made immediately.
But if measurement "at that moment" is not a requirement, how can you determine whether a wave function can collapse without a conscious observer?
It seems reasonable to me, btw, that a conscious observer should not be required to collapse a wave function. I'm simply wondering how that could be proven to a conscious being that this is the case.
After all, whatever experiment you do, the wave function of the entire experiment as a whole (including whether or not the electron's wave function collapsed independently, etc) could only collapse when the conscious observer observes its results, and in that collapse writing its own history retroactively, including whether or not the electrons wave function collapsed and thus what the result of the experiment was.
It seems to me as if the only way to say with certainty whether or not the wave function collapsed on measurement or on observation would be an experiment which is not observed, only measured, but the problem is that to determine the outcome of the experiment, someone has to observe it, at which point you can no longer be certain that it didn't collapse just now.
Clearly I'm not understanding something yet, so my question probably does not make sense, and if it is dumb, please feel free to ignore it, but thanks for reading anyway ^_^
@@Mercurius314 DCQE-experiment still doesn't need a Conscious Observer. it only requires that the which-way-path-information is available and not destroyed to collapses the wavefunction. the which-way-path-information can be stored in some medium and it doesn't need the observation of a conscious being
Truly the best and most understandable explanation of this phenom I've ever seen... thank you.
Glad it was helpful!
Thanks this understanding is the most clear and succinct explanation I have seen
The measurement interupting the wave makes sense.
Excellent Arvin.. Much of the woo and general confusion might have originally been avoided if OTHER terminology had been adopted to describe the collapse of the wave function.. Maybe like, interaction instead of measurement or observation... The show was done with beautiful Simplicity as always Arvin.
If it were that easy to explain by using a magical word such as "interaction" then why would we need such complex interpretations like the Many Worlds or the De Broglie Bohm🤔????
@@AlexTorres-qv3hv Odd, nobody suggested it would make it EASY to explain, Just that much of the unsupported woo interpretations might have been sidestepped...
@@AlexTorres-qv3hv maybe that's magical to you..
@@billnorris1264 its cause there's no such thing as "OTHER" terminology....even Einstein who was troubled by entanglement had no other way to call it but spooky.....there are contradictions between videos of this author, here he states it's interaction the cause of collapse but then in another video of a more advanced experiment specifically designed to rule out physical interaction by the detectors (DCQE) he simply states having no answer to explain the results which happens to be exactly the same as in the standard DS.....
Thanks for the video, keep the good work up❤👍
I like the way , you extract pulp of interpretation without going into rigrous mathematics.
I received a lot of questions regarding how the delayed choice quantum eraser experiment fits with this interpretation because some claim that this experiment "proves" the requirement of a conscious observer. Here's my answer to that: (And here is my video on the DCQE in case you don't know what it is: th-cam.com/video/0ui9ovrQuKE/w-d-xo.html ). First, you have to remember that the key to collapse is the recording of the which-path information. If the which-path information is not known, the wave will not collapse. The question is whether a consciousness has to "know" about this which-path information in order for it to collapse. This paper outlines such an experiment with the DCQE. When information regarding the path of photons was detected by measurement but not read by a human, the photon still collapsed into particle form. This suggests that consciousness did not play a role in the photon coming into existence as a particle. This Danko/Nikolic experiment outlines this: www.danko-nikolic.com/wp-content/uploads/2011/10/Yu-and-Nikolic-Qm-and-consciousness-Annalen-Physik.pdf . The one flaw with the paper may be that the authors did not precisely define what "looking" at the data means. I am not saying that I can explain everything about the DCQE experiment. I can not. But I am reasonably confident that consciousness does not play a role. We know that the entangled particles share the SAME probability wave, so when one particle collapses, the other collapses instantaneously. My opinion (purely my opinion) is that the entangled particles, linked through the sharing of ONE wave function, are connected in both space AND time through a process we don't yet understand.
Very well put. I think one thing that most people forget is that when we are talking about elementary particles, the normal newtonian laws of motion simply don't apply. Any macroscopic object behaves in the way that it does because the culmination of all the various wave functions of its constituent particles average out in clear predictable ways. Think of blowing on a dusty object and seeing all the various motes fly about. While that's not an accurate description of what's happening at the quantum level it's still closer than thinking of them as tiny marbles.
And once again Arvin, thank you for the video. To quote my favorite turtle from saving Nemo, "You totally rock dude!"
Bravo.
I think a common issue here is people's a priory definition about consciousness. The idea that it is somehow exclusively contained in the human body gives it this mystical property because you wonder how it then can interact with the physical world.
The "specialness" of the observer/measurement becomes completely redundant, when you consider consciousness as a fundamental property of the universe. In the sense that if atoms "touch", then both need to be "conscious" of each other. Of course there is nothing there that touches, but there is an awareness which is apparent in the strength of the interacting forces.
A radio can only recieve the signal of it has an antenna that is capable of being "aware" of the wave, capable of receiving the information. If nothing is aware then nothing can be transmitted, so "things" would pass through each other completely unnoticed.
So in that sense the measure instrument is a conscious observer. There is no fundamental difference to the human observer.
thanks a lot arvin for this video!.... but i have a question - you mentioned that when the detector is placed before the slits, the wave function collapses and forms a particle pattern but what about the delayed choice version in which we place the detector after the slits? in that experiment also, we will observe a particle pattern but how does the particle know that it will be measured at a later time so it must pass through the slits as a particle?
@@amaankhan8436 First let's be clear, there is never any "knowing" by any particle. As long as the wave function collapses BEFORE it hits the screen, it will always show up as a particle. Our presumption that the particle somehow has to "decide" what it is going to be before it goes through the slits is not the correct way to look at it.
Thanks for kicking the woo to the curb with this. You have saved me many moments of frustrating argument; this video is now a resource I direct people to when necessary. Besides, now I can give up my nerve-wracking belief in magic.
Excellent! Yes, please share because too many people falsely believe things that science does not support.
The only argument you brought was "there is no science". This isn't really a strong argument. Fact is, as long as we don't know what conscoiusness is, we can't say if anything is related to it. But it's also a fact that everything in the body depends on electrical signals, every thought and every desicion. It's stupid to say that we can "collapse the wave function on a specific point" that we want it to (or is it?), but it's also stupid to say that there is no chance that quantum physics may play a role in how consciousness works.
This is excellent. Thank you very much for your content.
Thank you, Arvin Ash. Thank you for your teachings.