Why Did Quantum Entanglement Win the Nobel Prize in Physics 2022?

Why Did Quantum Entanglement Win the Nobel Prize in Physics? PBS Space Time 2.78M subscribers Subscribe 37K Share 1.2M views 1 month ago Help Us with the PBS DS Survey Here: https://to.pbs.org/2022survey PBS Member Stations rely on viewers like you. To support your local station, go to:http://to.p … 3,562 Comments rongmaw lin Add a comment... ludvercz ludvercz 1 month ago Going against both Einstein and Feynmann, I guess they were super determined 4.2K Reply 137 replies charles mcdowell charles mcdowell 12 days ago Quantum mechanics feels like those math questions you got right as a kid, but when you showed your work, you were going about it wrong. 58 Reply 1 reply John Galt John Galt 7 days ago (edited) I admire you a lot for being able to explain complicated things and not be condescending about it. Thank you good sir. 13 Reply Karim Moubayed Karim Moubayed 21 hours ago I’ve been researching quite a bit about Alain aspect and quantum entanglement since I have an assignment to do and my brain is now completely fried every time I think I got it they would introduce a new idea I’m honestly thinking of failing it by now😅 1 Reply ProfessorMarvel ProfessorMarvel 18 hours ago Was wondering if you could explore the relationship of this to the quantum eraser. The double slit experiment fails to be predictable due to a worm hole between the entangled particles whereby time is irrelevant? Reply Joseph McGowan Joseph McGowan 9 days ago I really appreciate that you're bringing the remarkable work of these scientists to the public! But I do feel obliged to point out that Alain's last name is not pronounced like the English word "Aspect" but more like "Aspay", long e on the end and silent ct. :) 6 Reply Blue Jay Blue Jay 1 month ago I just want to say this is the only channel thats getting better with age, thanks for not underestimating your viewers. 1.1K Reply 19 replies kirk001 kirk001 2 weeks ago "Say the Lagrangian in front of a mirror 3 times..." I love these kinds of jokes... laughed so abruptly that my coffee went up my nose. LOL Thank you! 7 Reply Wim Woittiez Wim Woittiez 1 month ago Man, you're good. I have a master's in physics, but haven't been working as a physicist for a long, long time. You single-handedly revived my interest, updated me on more recent understanding, and helped me understand certain concepts that I should have understood at the time but didn't. 404 Reply 18 replies Silh S Silh S 12 days ago 1:58 I've heard about "quantum leap" but hearing "quantum balls" is an interesting articulation. 10 Reply 1 reply Christopher Perisho Christopher Perisho 2 days ago I'm with Einstein on this one. I have a hard time accepting there isn't a hidden variable somewhere. Reply GodOfTalesYT GodOfTalesYT 3 days ago So what your saying is if we can figure out how to make things be una indecisive state then we can control the information on the other place at the speed of light. This also proves how everything truly is connected and shows an almost similar structure to Bluetooth in my opinion. Reply Tato Arg Tato Arg 1 month ago (edited) As a non-physicist, I feel I won something whenever I can follow your videos all the way to the end. 715 Reply 25 replies Kunal Shukla Kunal Shukla 10 days ago Great explanation, at 3:04 the coefficients of the basis states at the RHS needs to be square root. Reply ChocInspired ChocInspired 3 weeks ago What a time to be alive. I'm 8 mins into this and clueless but just happy at the strides science has made. Incredible. 41 Reply 2 replies DStecks DStecks 3 days ago Doesn't the very notion of a physical process being "instantaneous" throw a wrench into relativity? For something to occur instantaneously, that would imply two events occurring truly simultaneously, and that would seem to imply a preferred frame of reference? Reply Abhishek Soni Abhishek Soni 11 days ago Awesome explanation 👏 1 Reply darron pattel darron pattel 13 days ago The real mystery is why they would give people like Ben Bernanke and Alan Greenspan Nobel prizes.... 2 Reply Chip Gruver Chip Gruver 1 month ago It blows my mind that in one hour you have 25,000 views about an obscure problem in quantum physics. I am glad to be in the company of my nerd brothers and sisters. There are more of you than I suspected. 515 Reply 34 replies Extremeredfox Extremeredfox 8 days ago The biggest issue with the scientific community is the strong willingness to cling to dogma and ostracizing those that challenge the status quo. Scientists are human, but we have to put away hubris and be open to challenge and the testing of everything. This needs to be the case even if it results in previously established hard work being sent back to the drawing board or us being proven wrong. It's chilling the number of brilliant scientists whose monumental contributions were only acknowledged, not by practical analysis by the scientific community, but said individuals being extremely determined to go against conventional wisdom and prove their worth. Who knows how many scientists that were brilliantly on to something, but backed down from pursuing it, as result of ridicule and negative support by the scientific community. For those that do preserve, and their findings demonstrated as plausible, it's a bit irritating that all of a sudden, the scientific community supports and backs these individuals, pretending as if they were unbiased, and never demonstrated unnecessary ridicule or blatant disdain, during the initial process. 1 Reply Roy Fritz Roy Fritz 1 month ago How Matt can infuse humor into these extremely technical episodes as he did in the last Q&A answer is truly brilliant. 33 Reply This Can Be Pronounced This Can Be Pronounced 9 days ago 9:03: I think the quote you wanted is "Difficult takes a few seconds. impossible? A few minutes." Or maybe I'm thinking about different wormholes. ;) Reply Lochvast Lochvast 2 weeks ago What does this mean for determinism? Are we still ruling out these logical loopholes before we are certain? Or has it really been proven that non-locality for these entangled objects is reality? Reply 1 reply Reginald Neale Lasala Reginald Neale Lasala 12 days ago Congratulations to this years nobel prize winners. brilliant work. thanks for adding to the universe's entropy! to more disorder! cheers! 9 Reply Waverod Waverod 1 month ago Thank you for pointing out that Bell's Inequality and the experiments honored by the Nobel Prize only rule out local hidden variables theories. I'm not saying I'm necessarily advocating for pilot waves or any other non-local theory, but it's been annoying seeing videos discussing this topic completely ignore that they may be disproving locality rather than hidden variables. 261 Reply 52 replies Farmer John Farmer John 1 day ago Super determinism makes sense if we live in a matrix. Maybe spooky action is really a glitch in the matrix. Reply Schmitzelhaus Schmitzelhaus 1 month ago This is legitimately the first time someone actually described fundamental quantum mechanics in a way i could at least get somewhat of a grasp of the concept. You´ve definitely earned a subscription! And you´ve earned it the hard way since i´m not all that clever. 😅👍 48 Reply 3 replies Gaisma Tevi Gaisma Tevi 9 days ago I'd say that our own perception defines the state of the ball Reply Fred Planatia Fred Planatia 1 month ago I love PBS Spacetime! This episode puts together so many of the elements that give me pleasure. Thank you Matt and team for another informative episode enlightening us lay persons on the sometimes weird world of physics, including the right measure of whimsy to make it digestible. 8 Reply 1 reply Frederick Lynch Frederick Lynch 12 days ago No different than Schrodinger's Cat - the observer does not know which box has the white or black bowl, and he can't know until they open the box, therefore, they too are in super positions - it is the same as entanglement Reply Kris Cadwell Kris Cadwell 1 month ago The episodes where you describe experiments and how conclusions were drawn from them are my favorite. Please do more. 151 Reply 2 replies Jacob Saint-James Jacob Saint-James 8 days ago What are prevailing attitudes on (a) whether the entangled pair are truly two separate objects or merely appear so to mind and its instruments; (b) whether the arrow of time can be violated with information being imparted teleologically, such that the observation (or a greater/universal superdetermined moment) is causal to the preceding quantum state Reply Tragene Tragene 1 month ago My education is in business but my love is physics. I admit I do not have the brain to understand the in-depth aspects of all the branches of physics. This channel is awesome in helping me understand on my level. Thank you particularly as I have a really easy time understanding you and staying attentive. 11 Reply Indrajeet Singh Indrajeet Singh 13 days ago Whenever an idea thrown out by so called theoretical physicists isn't understandable, give them Noble. 1 Reply Robert English Robert English 1 month ago I love watching these! Especially the parts where my brain gets entangled, and then untangles a bit as the details are shown. I call it the "Neuro-quantum antistupification effect". 8 Reply 1 reply Robert Edgemon Robert Edgemon 2 weeks ago My guess, is because the people giving out the awards, don't understand quantum entanglement Reply juan cuello espinosa juan cuello espinosa 1 month ago 4:11 I appreciate you using phrases like "dogma" and heretic when referring to how the debate around quantum entanglement developed. It reminds us that even if science holds at its highest ideal that truth is what matters, it's a system acted out by humans, whom can easily lock down thinking that falls outside the accepted narrative 205 Reply 12 replies Ivan Ooze Ivan Ooze 12 days ago in the simplest, most basic form: what is an observer? what are the qualifications to be one? it kind of sounds like an observer has to be alive, and something about that rubs me the wrong way Reply blueckaym blueckaym 1 month ago Bell's Inequality is really complex, and while Bell himself tried to cover all possibilities (given that it was just ideas and not actual experiment yet) he still could have missed alternative explanations, like super-determinism and non-locality (and how know what else ... perhaps that assuming that hidden variables would be exactly corresponding to classical understanding, on which after all is always based the generally accepted conclusion that "there are no hidden variables"). While all ideas are interesting at least to consider and compare to each other, I don't think super-determinism is the explanation. Not because I believe in free will (Free will only need not knowing that something is impossible or inefficient :)), but because I think it will lead to ridiculous paradoxes as the conscious observer or retro-causality that the dogmas of the standard model lead to. I've been following the randomness-determinism / local-variables topic for years now, and have to say that most of them just repeat the common interpretation "hidden variables don't exist", and only few (I can think of 3 at the moment) that consider the other alternatives. And one of these alternatives is non-Locality, which as Brian Greene put it "Locality is dead". I'm grossly oversimplifying of course. Bell's inequality theorem doesn't kill Locality on its own, but when you consider also the experiments showing that sometimes it doesn't work you should at least consider that so far we've only seen a sub-set of reality and laws of physics in which Locality works, and that perhaps it's one of those classical ideas that we need to finally put to rest (or at least test very very much). As you said in this video, Locality can be described as the information/factors for a particle behavior encapsulated in that particle itself, which is indeed the classical thinking (which works fine for large non-quantum balls :)), but today we know of example where fields give birth of particles, or particles behaving like a wave (beside being quantizable as particle) ... So we should at least consider that what we observe as particles are just excitations of a field (which by the way is the official definition of a particle!), and as such it's actually very likely that that field determines (or at least influences) the particle behavior. We know of at least one field that is apparently an actual physical thing rather than just an abstract idea, and which sometimes behaves (stretches) faster than light, and breaks the 1st principle of thermodynamics - the Space-Time. Is it that difficult to think that we're just scratching on the surface of theory of fields? Even when we can see demonstrations on macro-level (ie non-quantum) of many otherwise quantum phenomenon? For example the walking droplets on a surface of (usually silicone oil) we can see that the pilot-wave is at least a macro-world phenomenon. But also we can see that the resonance (in combination with other factors like surface tension) can lead to stable configurations, like having several drops move in formation, and at exact distance from each other - like in crystal structure; or that small droplets can bring stability to large ones that would be unstable on their own. What I'm trying to point out isn't just that if we can see it on macro-level then it much happen on quantum level - that would be logical fallacy on its own. But that these phenomenons are result of geometry and wave theory ... but of which are valid for the quantum world and we should at least try to find (or disprove them) on quantum level. There is no theory or field in science that benefits from keeping assumptions as dogmas, not matter how practical are they in the real-life. There should always be a strive to UNDERSTAND Reality deeper, rather than just "shut up and calculate". Otherwise we'll see videos like "Bell inequality experiment shows local variables don't exist" for decades to come ... There are just too many unanswered question to consider the subject closed! 2 Reply Rahooligan86 Rahooligan86 8 days ago best channel on youtube! Reply AR Tech AR Tech 3 weeks ago Whether you understand it a little or a lot I just appreciate the opportunity to see more information on the nature of reality. There is so much we don’t know and so many ways to tease it out of the universe. The next couple decades are going to be wild. 1 Reply I'm Better Than You I'm Better Than You 4 days ago most replayed part is the end LMAO 1 Reply Radar Radar 1 month ago I think I'll dress as a Quantum Entangled Particle for Halloween this year and tell everyone I'm causing spooky actions at a distance. 139 Reply 9 replies Sickmanfudo Sickmanfudo 1 month ago These videos are always super dense and I've been watching them for years. But it wasn't until I became a nuclear engineer, over the past few months, that I came to really value and appreciate the science covered in these videos. They cease to amaze me! 1 Reply 1 reply Cosmos Cosmos 1 month ago I really love how you go in-depth into the comments at the end of the videos. Really stellar teaching there! 4 Reply 1 reply GodOfTalesYT GodOfTalesYT 3 days ago Why is it when u open the box that it forces to choose, wouldn’t they both be still in that state of undecided Reply Daniel Crespin Daniel Crespin 10 hours ago Planck, Einstein, de Broglie, Schrödinger and many other brilliant thinkers stubbornly opposed quantum mechanics. And they were absolutely right. Reply Vishwanath Veerni Vishwanath Veerni 7 days ago Be so great that proving you wrong gets you a Nobel 😂 Reply ThePostApocalypticTrio ThePostApocalypticTrio 1 month ago Dr. Quantum Entanglement has been working very hard in their field for years without the recognition they deserve. I personally congratulate Dr. Entanglement for their deserved Nobel win 215 Reply 17 replies Clay Farris Naff Clay Farris Naff 1 month ago Great stuff, Matt .... as always. The comment-responses alone were worth the journey! Reply GrandeTaco GrandeTaco 1 month ago (edited) When I first heard of Quantum Entanglement I was blown away, the more I learn about Quantum Entanglement the more I'm convinced that it's just two marbles of unknown color, in two boxes. Reply Rate N'Review Rate N'Review 1 month ago Rating you guys 10 out of 10 and as per my review, Awesome! Always have been and always will be and I HIGHLY recommend. haha. You guys always make this stuff illuminated and tangible. 1 Reply 1 reply James Lyons James Lyons 1 month ago Amazingly I was able to follow your descriptions of these developments and am very thankful for the work you put into it!!! 1 Reply 1 reply Mahrai Ziller Mahrai Ziller 3 weeks ago Proper feels for the shout out to Aleksander at the end. Sounds an inspirational person with a love of science, and a lovely tribute. Reply Luke Phillips Luke Phillips 1 month ago Taking my undergraduate physics classes can be just a constant state of confusion with a few moments of satisfaction attained by comprehending a concept that are quickly squashed by a new even more complicated concept to understand. These videos give me a fun, easy to understand dose of physics that is still new and exciting for me. 84 Reply 4 replies Ruben Hart Ruben Hart 1 month ago Waow. One of the best (and deepest) videos on this channel...! Matt O'Dowd is a beast in Physics. Thanks for making such advanced topics easier. Reply 1 reply Mike Anderson Mike Anderson 3 weeks ago I am just so amazed by the knowledge of the physicist. To understand these principles, write the formulas, explain something that you don't see, etc. Even if you simplify the explanation, the ordinary viewer like me will never understand this. Reply 1 reply Janus Last Janus Last 1 month ago Great episode. I'd love more episodes that start with a theoretical concept like "delay the measurement" and show how that is done in an experiment. 3 Reply 1 reply Chase Modugno Chase Modugno 11 days ago This wizardry is beyond my comprehension Reply Maarten Keus Maarten Keus 3 weeks ago (edited) What a sweet message for Alec and his family. Rest in peace my man 2 Reply p g p g 1 month ago As usual PBS Space Time does an outstanding job explaining complicated subjects like quantum entanglement - makes me want to study Physics - keep up the excellent work! Thank you! 55 Reply 1 reply Judd Roberts Judd Roberts 1 month ago Wonderfully focused and delivered with grace and humor. Luv the t-shirts! More of this! Thank you PBS Reply 1 reply Eddie Davis Eddie Davis 1 month ago I really think that given the proper math you could say it is basically an anti-form of the original, such that you are actually seeing the same ball from a different perspective in spae-time Reply Danish lau Danish lau 4 weeks ago Entanglement getting more weird I think. Even going through the polariser after the switch over by the Crystal,why can’t we take a couple of snap shot (pictures) at the same time and check the pictures individually by different person (very important)and see if the entanglement still explainable. Reply inigmatus inigmatus 1 month ago (edited) Dear PBS Space Time: is it possible that gravity waves could interact with themselves at great distances vs their source matter, in such a way as to explain the effects we attribute to dark matter? I wonder if there is a gravitational refraction effect taking place at a distance from other sources of matter, one that would create an amplification point to where the effect affects stars at the edge of a galaxy as if something else were physically there when its not? 2 Reply Matt Richardson Matt Richardson 3 weeks ago With the black/white quantum balls experiment, would it be possible to flip the state of the particle after the measurement has taken place? If so, the other should flip back right? Couldn't you send morse with that alone? Reply Ryan X Ryan X 1 month ago I hope that broad and long lasting impact of this channel on humanity will be remembered in the annals of physics history a hundred years from now. Wonderful job, all. 69 Reply 2 replies inigmatus inigmatus 1 month ago (edited) Wouldn't it be interesting if we were to use a supercluster to view a planet at the other end of the universe via gravitational lensing... and even more interesting, discover that we were looking at a rather familiar planet - that we were in fact looking at the back of our own planet via one incredibly weird effect of a looped but expanding universe? Reply David Lloyd-Jones David Lloyd-Jones 3 weeks ago Alain Aspect is one of those strange cases like Einstein after his boffo publication outburst of 1905: everybody knew that they had to give him a Nobel, but they weren't sure what for, or which one, and maybe some part of the whole thing was wrong. 'Course this whole Bell's Inequality thing is going to be with us for a while yet. We're just in the opening rounds -- again rather like the situation with quantum mechanics after Einstein's 1905 photon seemed to be the ring to hold the wrestling match in. Reply Sean Caceres Sean Caceres 13 days ago Why wouldn't we be able to drop signal repeaters along the journey out? Reply Tomasz Kostyra Tomasz Kostyra 1 month ago It's an excellent show and you are an excellent presenter! 2 Reply 1 reply Dubstepspl Dubstepspl 4 weeks ago Thanks man. How we can find particles that have quantum entanglement ? I know that is possible, but how we can do that ? Can we connect this particles to a bigger matter ? Can that particles travel throw another dimension or time ? Thanks for answer ! Reply Kathiriya Keyur Kathiriya Keyur 1 month ago Just wanted to say thank you for working this hard for people like us who are not necessarily scientists or someone important but just bunch of nerds(i say this very respectfully) who wants to learn more about the universe and its mysterious ways without getting to technical about the maths behind it.. I have got bachelor in physics and i have been watching this chanel since i was in grade 11.. to be honest you guys are a big reason for me choosing to go for a physics degreee..and i am thankful for it.. i liked every second of my studies just because of the curiosity that you guys put into me..thanks very much.. 28 Reply Muso Master Muso Master 1 month ago You’re a better science explainer than many I’ve seen. Reply 1 reply Ramen Vermicelli Ramen Vermicelli 1 month ago Would it be possible to launch a spacecraft toward Voyager that could act as a sort of signal booster between Earth and Voyager? The signals would still take the same amount of time to reach us, but because this craft would be closer to Voyager than the Earth, it could amplify and relay the signals from Voyager once Voyager's signal is too weak to reach us on its own. Reply Vietnam Czyk Vietnam Czyk 2 weeks ago So particle is entangled to particle, group of them is entangled with each other and how can single particle determine whole group and bum how it was before and ? detection method is one way of describing of what we are ready to see. thats why we cant find antimatter beacuse its maybe somehow "filling" the gaps between "dimensions" and at the same time cannot affect any of them or .. Its inside our universe or outside of it? Where, how and when universes hapen? Are all of them right now but without observer? what if its not pulling particles like gravity instead pushing particles like ions ... anyway... how does that affect electrons? do they have more dimensions thats why their spin is "weird"? like leaving its trace behind? or we humans are just able to see "past".... how does "feeling" of touch works .. bring back Einstein it was simplier :D Reply John L John L 1 month ago Well done Matt on your fluent descriptions. I have one question regarding Quantum entanglement and the principle of instantaneous action at a distance. Assuming the two entangled particles measured by Alice and Bob, are each taken in their spaceships going in opposite directions at speeds that create some measurable time dilation; when the instantaneous action happens, do Bob and Alice see the effect happen at the same time, or is the ‘instant’ measured as being at the relative times of each? If the latter is true, on one objective perspective, the action takes place at a future time relative to the other and creates an interesting dilemma. If the former is true (ie at a time agreed by the observer to be the same (not sure how), then Alice and Bob measure the ‘instantaneous action’ as taking place at different times. 1 Reply Ravinz Grewal Ravinz Grewal 3 days ago quantum entanglement behave exactly as Mirroring technique. Reply Yavor Tch Yavor Tch 1 month ago (edited) Matt, I love your series! One comment - Sabine posits that Einstein's "spooky action at a distance" is in reference to the instantaneous collapse of the wave function everywhere and not to entanglement. I'd be curious to hear your thoughts on that. BTW it'd be fantastic if you would collaborate on some videos together! 55 Reply 9 replies Zia Steele Zia Steele 1 month ago (edited) If the the universe is a simulation, could the programs encoding the laws of physics be a kind of nonlocal hidden variable or superdeterminism? Also, can you do a video on testing the simulation theory? Or conversely, if it’s impossible to properly test, could you explain why that’s the case? 2 Reply 2 replies simon6071 simon6071 11 days ago I have just learned that "If you influence one of the entangled photons, rotating its polarisation direction, the direction of polarisation of the second photon stays uninfluenced." In that case, I doubt if the pair of photons are truly in a state of quantum entanglement. 4 Reply 3 replies Randy Scott Randy Scott 1 month ago Wonderful summary. Superb clarity (on a subject that really isn't at all clear). Great graphics. Thanks so much. Reply 1 reply Sebastian Fiel Sebastian Fiel 3 weeks ago 1:24 I'm no physicist but I can assure you this is 100% accurate Reply m m 1 month ago If you can prove Einstein wrong in any way, you will win the Nobel Prize in Physics. 2 Reply michalchik michalchik 1 month ago I remember reading about the Bell inequality and the epr experiment when I was a kid and I'm really glad people went through and did the experiment. One thing that has puzzled me though is why took that experiment to convince people of non-localities/ indeterminism. The thing that really convinced me and frankly it was shocking and very disturbing was the first experiments with single Photon and single electron two slit diffraction. To this day I'm unclear why a careful examination of that seminal experiment isn't as clear an illustration of non-locality/ in determinism. If anyone wants to explain how you can get single Photon and single electron to Slit diffraction patterns in a local/deterministic universe, I would be interested. 24 Reply 2 replies Sunlight Swift Sunlight Swift 1 month ago Now finally my coworkers will understand why I've been so excited by quantum entanglement over the years. Reply Alex Bowman Alex Bowman 1 month ago This means it may be possible to send an instant message across light years (perhaps aliens are communicating this way) and not only will the receiver know the question before it is sent but the sender will know the answer before they send the question. 1 Reply 1 reply Gabriel Fair Gabriel Fair 1 month ago I would love all these videos organized into a playlist ordered by increasing complicity so new ppl can get started 3 Reply 2 replies Ted Toal Ted Toal 1 month ago I’d like to be able to understand the proof of Bells theorem. Is that virtually impossible without having a PhD in quantum physics? Another thing I’m curious about and would like to do if possible. Could one write a program for a quantum computer that would essentially demonstrate the same results as the Alene experiment? Perhaps it wouldn’t include the demonstration of faster than light correlation, but could it demonstrate the violation of the hidden variable inequality? Reply Feradach mac Tralin Feradach mac Tralin 1 month ago I agree with the formula being helpful. I know I won't understand the the math but it gave a great sense of what goes into the math and therefore what makes up our universe. Reply 1 reply Rob Babcock Rob Babcock 1 month ago I'll chime in with support for episodes like the previous one! I'm nowhere near good enough at math to comprehend it all but seeing these kinds of things explained does at least give some insight into things in broad terms. While I don't really understand them I'm glad someone does.😁 27 Reply 2 replies ruben martinez ruben martinez 1 month ago I'm no scientist by any means, I'm just an IT guy with a passion for physics and I just want to say thank you to you and everyone in the YouTube science community for bringing the joy of science to a layman like me, once again thank you ❤️ 13 Reply 1 reply Mark Campbell Mark Campbell 1 month ago Quantum entanglement is usually referring to the entanglement of energy in double bonds to the point of electrons and the bond breaks or the election spins off the halogen or transition metal nearby. The superposition and spin flip issue is the functional quality of the NMR or MRI imaging system. They appear to be mixing their metaphors. Reply Felix Reith Felix Reith 1 month ago Recently discovered This Channel, this is just amazing. You always ecxite thoughts in my head how beautiful and mysterious Our universe is. Thank You for that, Keep Going Reply SpazzyMcGee1337 SpazzyMcGee1337 3 weeks ago I need to know more about Bell's hidden variable metric, because I still can't convince myself that hidden variables in the form of a very tiny random number generator is not an option. Reply B2 Mark B2 Mark 3 weeks ago I wish the science surrounding neutrinos got more funding/attention, I really think it’ll lead breakthroughs that’ll change what we think we know 😅 Reply Noah Ollington Noah Ollington 1 month ago I loved how you stepped through the progress made in good timing, and being engaging. Love watching the vids! Please don't stop 😅 24 Reply 1 reply Mia Harfe Mia Harfe 3 weeks ago Basically, this is new and isnt something we learned back in highschool/college... Mindblowing stuff 🤯💦 Reply C Colborn C Colborn 1 month ago I have a feeling Feynman wasn't just "blindly following dogma", but probably had a deep, intuitive, and fundamental understanding of the underlying physics Reply 1 reply Luis DJ - Intecnogy Luis DJ - Intecnogy 1 month ago What a brilliant and clear explanation of quantum entanglement! 1 Reply 1 reply Gursagar Singh Gursagar Singh 1 month ago Another great video by the pbs spacetime team. I have just one query, in the wave function that was used for the example of superimposed back and white ball states, shouldn't the normalizing factor in front of the two superimposed states of | w b > i.e., first ball white and 2nd back black and |b w > i.e., first ball black and 2nd ball white be 1/(square root 2) instead of 1/2. The normalizing factors in front of the superimposed states when multiplied with their complex conjugates give the probabilty of finding the system in that state when observed. In our case, assuming the system can collapse into the two superimposed state equally likely, the normalization factors should be 1/(square root 2). That would mean, that on observation, the superimposed entangled system has 1/2 probability of collapsing into | w b > and 1/2 probability of collapsing into | b w > and the sum of both probabilities add to 1 as it should assuming there can be no other way for the superimposed entangled system to collapse into. For the normailzation factors of 1/2 shown in the video, the probabilities of the sytem to collapse into either | w b > or | b w > would be 1/4 and hence the probabilies won't add to 1. I am certain it was a typo and as I said amazing amazing video and keep up the good work. Reply 2 replies UFVA UFVA 3 weeks ago Thanks, now I have 2 things I would never understand: Theory of General Relativity and Quantum entanglement 😅 Reply Zatarita Mods Zatarita Mods 1 month ago (edited) I've always wondered if quantum physics issues arise because we're 3d creatures trying to understand multidimensional objects. What if entangled particles share a higher dimensional coordinate. Like how polynomial equations can have two answers, entangled particles intersect our 3d reality at multiple locations. So information isn't traveling "faster than the speed of light" but instead it's basically just one system connecting the two points in 3d space. This could also explain the weird shape of atomic orbitals and stuff in chemistry too. Those might be "perfect shapes" in higher dimensions. 13 Reply 13 replies Andrew Andrew 7 days ago How is it possible to gain knowledge faster than the necessary information would take to get to you? Reply 6 replies Gatito Dura Gatito Dura 1 month ago (edited) I think Einstein new that quantum entanglement was right, but refused to accept it, and the reason behind is that Einstein was a very spiritual person and really wanted to prove that there's some consciousness guiding or directing everything from behind, not a totally random "spooky accion" as this latest nobel's price winners had shown. Thus, even if he knew the truth, didn't want to give up in his spiritual quest. But in my modest opinion he was trying to prove spirituality in the wrong place. I admire him so much. Reply 1 reply creedstat creedstat 1 month ago In the astral my particles became temporarily embedded in a glass windshield I had to peel myself out off of it it definitely felt real and really weird Reply qmurec qmurec 1 month ago When a photon passes through a vibrating crystal as mentioned in the video: how does one know that the photon leaving the crystal is the same as the one that entered it? Reply The God Emperor The God Emperor 1 month ago I like how this can be possibly how cross universe communication works in various Sci Fi :P 1 Reply 2 replies Zapped Guy Zapped Guy 1 month ago I realise that most universities have limited budgets and so a head of faculty will deny research funds to scientists who are bucking the favored theory of the day but I love how many discoveries have come from people who refuse to give up on their own theories.It's what science is all about. 14 Reply 1 reply First name Last name First name Last name 1 month ago If one particle can affect another instantaneously over any distance, it sounds like the two are linked in some higher dimension. Reply Liann Black Liann Black 3 weeks ago Lot of people wanted to prove this before and even with free energy through resonance. Sadly we have lost a lot of budding physicists. Stefan marinov to say the least. R.I.P died trying to tell the world about this and the quantum state Reply Christian Corralejo Christian Corralejo 1 month ago With this experiment, does it make quantum communication more possible, less possible, or the same as before? I’ve seen a video before about how quantum communication is ultimately impossible and was curious if this changes anything. 1 Reply 3 replies Andrew Wright Andrew Wright 1 month ago Can we have a video on how various theories of everything like string theory answer the question/paradox of spooky action at a distance? 1 Reply 1 reply Sponge Arcade Sponge Arcade 1 month ago (edited) I have a good question for @PBS space time what happens if you induce a material imbalance in a bar magnet , i.e a weight or Density change in the material of a bar magnet and then magnetize it, will it mimick an altered magnetic field centre, or even extrude a permanent magnet to induce an altered centre through density variation. If so than yes my yo-yo overunity engine works, as a magnetic field always finds the centre of a mass so to induce a mass variance will it mimick a change in polar centre, I say mimick as the magnetic field will still be centred but at a alternate measurement due to the density change across the material. This comment and the theory and technology and my Yo-Yo generator are all copyrighted ©®™ Reply 0089 Satwik Padhi 0089 Satwik Padhi 1 month ago I'd like to hear Feynman's explanation on why he thought that quantum mechanics was always right. That would be a very informative session. 8 Reply 3 replies Keyboard Warrior Keyboard Warrior 1 month ago Soul goes from 1 body to another after death. Is a kind of similar concept, where conciousness gets teleported into diferent matter through Quatum entalgment. Now it would be fun to figure out if one could guess the teleported particales new state or location, besically guessing the rebirth or respawn location. Hacking matrix haha ! XD 1 Reply 1 reply murf murf 1 month ago The one thing that never made sense to me Is that how do you know the two particles are entangled to begin with if you can't measure it without the wave function collapsing? Reply 1 reply Sh Ko Sh Ko 1 month ago (edited) Is entanglement a higher dimentional connection between quanta? If one of the entangled particles is relatively stopped as much as possible and the other(or the other inside a box) is accelerated to the speed of light. And then they meet together after a random period of travel(one spun more and the other spun less - we assume that it really spins). At the moment will they maintain the entangled state? If so, the experiment shows that entanglement is not deterministic and partly time-independent. Reply TheBussaca TheBussaca 1 month ago So my premise is, they've basically created a digital communications device that will work instantaneously, any where in the universe as long as the communication devices are a matched atomic set. by flipping one the other flips at the same time basically transmitting a 1 or 0. computers at both end decode the flips and you should be able to send data/voice instantaneously at whatever speed the computers can talk to each other. Reply Charon ME Charon ME 1 month ago is there any way (even theoretical) of checking whether the other entangled particle's wavefunction collapses at the same instant the first entangled particle is measured? And if it does indeed collapse at the same instant would this be a violation of the relativity of simultaneity? Reply 1 reply Scott Wilder Scott Wilder 1 month ago I'd straight up tell Rich he's less than a scientist if he opposed my testing him right/wrong. That's exactly what being a scientist is. Always testing things right and wrong hoping for the most accurate outcome. 14 Reply 4 replies ChrisBrengel ChrisBrengel 3 weeks ago (edited) What was the experiment that used distant star light to make sure there was no way local information could interfere with the experiment? Reply The Ether The Ether 1 month ago After watching this i kinda feel like we can travel anywhere in world with anywhere door but with a little bit predefined information for all the places. Reply Samuel Rodrigues Samuel Rodrigues 1 month ago Hi Matt, guys.. what happens if u throw one of the entangled particles into a Black hole and measure the other from the outside of the event horizin? And what if it would be possible to measure first the one from within the event horizon? (Can the info actually "escape" the BH?) 1 Reply 4 replies HughEMC HughEMC 4 weeks ago I think its amazing Einstein can conceive a concept in theoretical physics "think naaaw I really don't agree with that" then have his concept proven correct decades later. I doubt Albert would mind being wrong about this one. Reply Varun Sharma Varun Sharma 1 month ago That person was so right in being in awe of universe trying to understand itself Reply 1 reply JS 2K JS 2K 1 month ago Love that you guys do tributes for people in the community! 11 Reply 1 reply twicebitten thasme twicebitten thasme 1 month ago The suggestion of Hidden Variables still existing despite an inability to determine their existence reminds me of paywalls for research documentation. One can be absolutely certain that without special permissions, whatever is hidden will remain hidden until a suitable workaround has been initiated/installed. This workaround wouldn't necessarily affect any data yet to be discovered however, interference can not be ruled out entirely. I'm certain other analogies are more accurate and succinct but this was the first image I imagined. As always, more food for thought. Thank you for sharing! 1 Reply 2 replies Dance Doctors East Valley Dance Doctors East Valley 4 weeks ago (edited) For the thought experiment to work with the balls and boxes, don't we need light to determine the color of the balls, and that speed affects the results no? If the objects were different shapes and we opened the earth box in the dark...we still are measuring at the speed of electrical impulse from the brain, so that's slower than light. Well good job you got me thinking this morning. Reply Ami Loh Ami Loh 9 days ago What are the practical application of this Reply No Good No Good 1 month ago Doesn't the atom releasing the photons see a particular polarizer at the time of creation back through the calcium crystal regardless of which one it is directed to for measurement? You still are affecting the creation of the photons even if you arent doing detection in the same state that the system was in when you generated the photons. If that is the case with his setup that is and the path from polarizer to exited ion beam was not opaque. Reply Lenny Newball Lenny Newball 1 month ago Coming from a very basic understanding. Is this how you would communicate over long distances instantly for example like in Star Trek when they're talking to Starfleet via video communication instantly what other practical applications could something like this be used for? Just some ideas I had while I was writing this communication from Earth to Mars from Earth to the Moon with no delays? And thanks in advance for all the answers or suggestions Reply 1 reply Zachary Wong Zachary Wong 1 month ago Fantastic video as always, Space Time team! Superb explanations here, and the boxing at 3:50 was very clever! 6 Reply Norman Goldstuck Norman Goldstuck 1 month ago This work was done so long ago and known to those of us with only a basic physics degree, you have to wonder why the Nobel committee took so long. In the interim there have been many apparently more mundane awards. How about a video on that. Reply 1 reply M.K. Wallner M.K. Wallner 3 weeks ago Once we can totally understand the physics behind entanglement, instant communication with alien worlds will be possible. I venture further to say that this will also lead to reaching instantly any place in the universe without having to travel the distance. By then we will also be able to transfer our "self" into artificial bodies, making us virtually immortal. Unfortunately though, all of us alive today are still evolutionary garbage. But future generations will live the dream and populate many of the infinite worlds this and other universes are offering. 1 Reply 1 reply Zachariah Drown Zachariah Drown 5 days ago Thank you alex ! Reply Charles Vincent Charles Vincent 1 month ago Wouldn't the entangled pairs identity have been determined locally before the split? Measuring one doesn't change the other, we just now know the difference which combined equal the whole. Reply Midgard Midgard 12 days ago I'm so glad I found this channel you are fantastic to listen too 4 Reply Matt Graves Matt Graves 1 month ago For some reason, this year's Nobel prize has really grabbed my attention and ever since I've been watching videos on quantum physics, quantum mechanics quantum entanglement quantum fields... And quantum computing because I'm a software engineer. I'm like obsessed with it for some reason, I'm not sure why. I think the more videos that I watch I'm going to understand it all the sudden any more than physicists understand it already which is ...not as well as I would like. 9 Reply 2 replies Михаил Мищенко Михаил Мищенко 1 month ago 5:01 I'm not an expert in physics, but are you sure you wrote Bells inequalities correctly? Shouldn't there be a modulus sign also at the end of left parts? Either way, thanks for the great episode! Reply 1 reply Man in The Moon Man in The Moon 3 weeks ago I'm wondering whether this 'puzzle' is rendered more difficult to 'solve' while words like "quantum balls" are floating around. Reply Douglas Engle Douglas Engle 2 weeks ago The main question is whether quantum entanglement can be used as a faster-than-light signal and that answer should be addressed in these public forums. If there are two entangled particles when one is measured does the other particle indicate it has condensed into a known state such that if one particle was measured on one side of the universe and some device monitoring the other entangle particle on the other side of the universe would instantly see that the other entangled particle had been measured? If the requirement is that the second particle has to also be measured to determine its quantum state that would have of course cause it to loss its entanglement canceling the ability to have instant communication. This would still allow for faster-than-light communication. If the particles were separated by light years with particles than could maintain their entanglement indefinitely then a monitoring point of some time less than the light years between them could be chosen to determine the entangled state that would result in faster-than-light communication. 2 Reply 4 replies Jake Wright Jake Wright 1 month ago (edited) If you had a 100 light year long hockey stick and twisted it at 1 end, the other end regardless of it being 100 light years away would instantly twist too. Yet if you observed it with a telescope the further you looked back nothing would happen for a long time. ... Think about it Reply Andrew Befus Andrew Befus 1 month ago (edited) Would be nice if they could determine whether a quantum state was collapsed without collapsing it. Or, even if it did collapse, determine if it was collapsed by the observation or by it's entanglement before being observed. Reply 1 reply Ed Sumpter Ed Sumpter 1 month ago Great episode. Thanks for explaining simply (well .. as simply as possible for this type of subject). Survey only took 7 minutes and I hope next season comes soon!! 5 Reply Gabriele1979 Gabriele1979 3 weeks ago So... If a particle falls beyond the event horizon of a black hole, is it entangled with one left outside? Reply Erotemic Erotemic 1 month ago I'm sure this thought has been explored before, but: what if entangled particles are connected by small wormhole, so locality is not violated? This seems to be difficult to test, but is this a possible alternate explanation? Do string theorists have anything to say about it? Is there a way to create entangled particles without initially bringing them close together to "establish and stretch" the wormhole across a large spatial distance? Reply 1 reply Travis Bewley Travis Bewley 1 month ago Now, I only teach Middle School science but the thing I can't seem to wrap my head around is the causal relationship between observing and the reaction. Like, how is it that my brain interpreting the information my eyes took in had any more impact on what's inside the box then the light ricocheting around the box and hitting any non-living matter. Am I taking this all to literally? What counts as a observation? Reply Anarchy Antz Anarchy Antz 1 month ago Now that Einstein has been proven wrong about nothing can go faster than light and has shown that causality was not affected. Does this mean we can finally seriously start looking into FTL communication or even travel without it being classed as "fringe" science? I was also surprised at Feynman's reaction given he has often been shown to buck the trend of convention which is really the only way we can now try and break the dead end we have seemingly painted ourselves into. Reply 1 reply Ram Kz Ram Kz 1 month ago (edited) Not a physicist but love those videos. I was wondering could the information be traveling in time instead of space ? As in when we make the measurement on one end the information is affecting the particles cross time as in "Backwards" in timeline? So basically our decisions not only affecting the future but on quantum level also the past ? So collapsing the wave for a particle in present collapses the wave of that particle thru time ? Or maybe i am just talking out of my ars xD. Reply 1 reply Class Ofrass Class Ofrass 1 month ago Could the Entropic Uncertainty principle be used for the double-slit experiment? What do you think the results would be if light particles were able to be tricked into giving up more information? 6 Reply LearningUser LearningUser 1 month ago “I would rather have questions that can't be answered than answers that can't be questioned.” ― Richard P. Feynman Apparently that was a lie. 2 Reply 1 reply Aikani Kuluksi Aikani Kuluksi 1 month ago (edited) Has quantum entanglement been experimentally verified with subluminal particles, such as fermions, or have all experiments involved photons? In other words, has it been experimentally verified to be a potential property of any particle system, and not only photons? Reply 2 replies J Pin J Pin 1 month ago This is what being human is all about - coming together and discussing things that are so [seemingly] beyond human understanding. Looking at these things from different perspectives is extremely important and can be held we advance as a species. I know we're trying to avoid philosophy in these discussions. But how can we overlook intelligent design in this entanglement discussion? Is it also possible that intelligent design created a system that keeps us in the dark? Can the ENTIRE universe be PURE Chaos ( a game of chance)? And only when we try and take a snapshot will it look like something that's in balance? Or is every single Atom a self-contained entity that is able to pair up with other atoms in order to create life itself? Reply Steve Nesbit Steve Nesbit 1 month ago I got my BA in Physics in 1972... One thing hasn't changed.... We know Quantum Mechanics is correct because the Mathematics for it is always correct in its predictions. Reply 1 reply af2600 af2600 1 month ago I'm going to file this in my brain in the same compartment where I left calculus... lol. Seriously though, thanks for explaining this Reply M Ormsbie M Ormsbie 1 month ago 19:41 LOL For real, it was a relief to hear it takes 10 years of coursework to learn the Lagrangian because that video was a trip, one I immensely enjoyed despite my very mathematically repulsed brain. Love your work. 9 Reply Jake Bunch Jake Bunch 1 month ago So if we have the ability to invert an entangled particle’s spin and the ability to measure the other particle changing spin in response, does this mean we can relay information, bit by bit, faster than light? I’m assuming you would have talked about this if so, so maybe a better question is why can’t we do this? I’m assuming the very act of measuring the spin of the “receiving” particle would somehow ruin the information being relayed, but in what way? Reply 1 reply Jeffo-wup Jeffo-wup 1 month ago (edited) If the probability function of a particle (like an electron) allows for it to collapse at any point in the universe, albeit a very nearly zero chance outside the boundaries of the atom, does this chance also include the possibility of manifesting in space beyond the observable horizon? Reply 1 reply Yanna Mama Yanna Mama 1 day ago Am I the only one who doesn’t get it ? He says in the first example that by finding out the color of one ball you immediately know the color of the other ball, No travel of information needed. I don’t understand how the second example is any different and I’m trying very hard to 😩 Reply Ben Skala Ben Skala 1 month ago So does this explain how the teleporter on the Enterprise worked? Reply Marc Cheung Marc Cheung 1 month ago The passing of a current through a vibrating quartz crystal was pretty genius. Does quartz refract light the same way a prism does? Reply 2 replies Andrew Connell Andrew Connell 1 month ago I was moved by the tribute to the young man who was a sponsor of the channel. RIP Alex. 🙏 11 Reply 1 reply PotatoJunkee PotatoJunkee 1 month ago Very off topic, but has anyone thought about what kind of wave function a pre big bang (or at big bang) universe COULD have? Reply 1 reply Vlad Drakul Vlad Drakul 1 month ago Matt looks tired. He needs a well deserved vacation! Great stuff of course! 1 Reply 1 reply Zippidee Doodah Zippidee Doodah 1 month ago If there's a link between twins and quantem entanglement that could explain why their bond, or communication patterns are so tight. Reply 1 reply Johnny Repine Johnny Repine 1 month ago Have you tried reciting the Mobius equations into the mirror to teleport like Harry Keogh from Brian Lumley's Necroscope series? 1 Reply 1 reply Sean Smith Sean Smith 1 month ago When two entangled particles resolve their respective entangled properties, it’s supposed to be simultaneous. But what if the entangled particles are not in the same frame of reference? To what observer would it be simultaneous? Reply 1 reply lystfiskerlars lystfiskerlars 1 month ago Biggest criticism of Zeilinger is that he always makes it more mysterious than it needs to be. 64 Reply 10 replies chucku00 chucku00 1 month ago Imagine being named Aspect (it has the same meaning in French) and dedicate your life to finding new ways to describe the universe... 1 Reply william godfrey william godfrey 1 month ago I did my BSc dissertation on exactly this subject. It's so interesting. Reply 1 reply ExaltedDuck ExaltedDuck 1 month ago So an idea struck me years ago, and I'm curious what people more travel ned in the subject matter would think... Since photons travel at c and what we know of relativistic effects is that time would dilate infinitely at c. So from the perspective of a photon, no time passes. This would necessarily mean that from the photons perspective, no time passes between emission and absorption. It is simply energy in one system's local then immediately energy in another system's locale. So the idea is that this could then imply that a photon cannot be emitted unless it is also absorbed. Since no time passes in it's frame of reference, it cannot decay. But can it be emitted "into the ether" without an absorbing partner? Is the universe an open or closed system? Can a photon intended for one target actually be intercepted by another target? Or would it have known its destination even before that destination received the impulse to be in its path? To that end, is the concept behind the experiment described in this video even sound? Or are we just arrogantly assuming that our apparent free will might be a little illusory than we usually want to believe? Or to tie it back to the emitter/absorber framework, is that photon the cause of excitation in the absorber, or excitation of the absorber the cause of the photon? Reply Bryan Schmidt Bryan Schmidt 3 weeks ago PBS has always been one of America's greatest creations. Reply Jules8386 Jules8386 1 month ago Would love to see the math on this theory. 1 Reply 2 replies DarkPortal DarkPortal 1 month ago This, has consistently been the most in-depth youtube channel when it comes to science. Other channels talk about how weird quantum mechanics is, without explaining anything. They just talk about strange stuff without the history and without the interpertations. This channel talks about alternate explanations and some mathematical reasons as to why we believe quantum mechanics works the way it does. Bravo! 7 Reply 1 reply Matthew Exline Matthew Exline 1 month ago (edited) Since there are actually 10 dimensions and space-time is curved, maybe quantumly entanged particles actually are not far apart from eachother, when viewed from the correct multi-dimensional point of view. Thus in a sense they are not acting upon eachother "at a distance" at all. Reply doctormoobbc doctormoobbc 1 month ago What happens if you "observe" the information about the ball on earth (therefore instantly knowing about the entangled ball on the moon) BUT all of the data is then deleted and the memory of everyone involved is wiped. Has the wave function still collapsed or does it go back to a state of superposition? This sounds more like philosophy than physics. Reply Joe M Joe M 1 month ago Hi i have a question if anyone could help, so in regards to the 50/50 black and white ball box example, can it be truly 50/50 black white when you include all the hidden variables like who packed the box, right or left handed, positioning, entrance/exit location things like this? So is it then an invalid term used as nothing can truly be 50/50 without some sort of variable influencing one or the other even if its infinitesimal? Thanks Reply 1 reply Parthasarathy Venkatadri Neo Vlogs Parthasarathy Venkatadri Neo Vlogs 1 month ago Does that mean we can finally in some future have devices that lets us communicate to far reaches of the universe at a speed faster than the speed at which we thought causality could travel. Reply 1 reply Steven Arvizu Steven Arvizu 1 month ago While I know scientists vastly smarter than I will ever be have come to the conclusion that string theory may be the answer to these long thought problems, the inner me hopes that some Einstein 2.0 comes along and finds out it’s not so difficult and indeed we were just missing something small that explains quantum physics more simply. Mostly because it’s hard for me to keep up with how the universe works when it requires math to understand it 😅 Reply Markus Pfeifer Markus Pfeifer 1 month ago I think it more likely that the universe is local, but there’s no hidden information. When Alice measures particle A in instrument configuration theta, all she knows about particle B is that if Bob measures it in configuration theta or -theta, it will definitely have the opposite (resp. same) value. In all other configurations, the result is known only up to a probability predicted by the wave function. As far as Alice is concerned, the configuration of Bob’s measurement instrument has become entangled with Bob‘s particle. 3 Reply 1 reply Matt Tirado Matt Tirado 1 month ago What it means is that the Universe in itself is a field, and every point in spacetime is accessible instantaneously. Reply Horney Kane Horney Kane 1 month ago Suggestion: Do an episode on whether humans will be able to -- instead of travelling at near light speed to Earth like planets -- live in intergalactic near vacuum & near absolute 0 space indefinitely at slow speeds. Ideally, using E=mc^2, we would harness maximum energy from interstellar atoms to sustain ourselves. Reply 1 reply Andrew Greene Andrew Greene 1 month ago is it possible that entangled particles may have a different location in spacetime but actually reside within the same location in the quantum world? Reply Peter Kelley Peter Kelley 1 month ago Thia is one episode where everything went over my head. Tries to pull Dr. O'Dowd back down to the level of the rest of us. Reply 1 reply TheExplodingChipmunk TheExplodingChipmunk 1 month ago So, I recently rewatched the video "Is Gravity caused by Time?" and had a thought. Couldn`t this theory also explain what drak matter is without the need for any aditional particles or exotic forms of matter? If gravity is a result of mass and time interacting and the theories about more than three spacial dimensions are correct, couldnt dark matter just be normal matter sperated from us in those other spatial dimensions but in the same time dimension? So that the dialation of time by its mass causes gravitational effects in our three spatial dimensions despite them being seperated? Reply Red Nomster Red Nomster 1 month ago Question! Is there a fundamental limit on how large an entangled system can be (not counting super-determinism)? Matt mentioned particles and molecules for size scale -- I don't necessarily mean physical size of each entangled piece, but rather how many particles/molecules can be entangled at once. I'd love to hear if that is a field of research that's growing, or if that's not a relevant possibility due to some maths principle I/we haven't heard of just yet. Thanks! 14 Reply 8 replies poker bruh poker bruh 1 month ago Also, if everything is connected it would make things like communication through "psychic" abilities seem obviously possible and that actually could be communication faster than the speed of light? Wormholes seem like more of a possibility if everything is connected. Am I just way off with all this? Reply Mark Dimirco Mark Dimirco 1 month ago Okay I understand that as of right now the hard rule is that even though these influences can occur instantaneously, no actual information can traverse space faster than light. Is there any possibility that this can be theoretically worked around without causing reality bending paradoxes? I feel like humans can figure this one out, like a form of sub-light channel communications from Star Trek. If a ship set out with a communication "bank" of trillions of particles entangled to their counterparts in a quantum computer back on Earth that there would be a way to manipulate those particles either way to send some kind of usable signal across huge distances without any delay? Reply 1 reply HiZ RedShift HiZ RedShift 1 month ago We’re clearly missing a big piece of the puzzle and I know it sounds silly but could something like Star Trek’s subspace actually exist? It was amusing when Picard was having a back and forth conversation with someone light years away but the evidence keeps piling up that information can be transferred faster than light. If civilization is still around in 200 years I wouldn’t be shocked if we’re somehow taking advantage of spooky action at a distance :) Reply XiEpsilon XiEpsilon 1 month ago could quantam entanglement be used for communication? for example, instant communication with and control of drones/rovers on Mars? Reply 1 reply strato stratorunner strato stratorunner 1 month ago The basic phylosofy of this is so profound that we can now say , that there is a ''present'' where ever you are or looking accross the univers. Not in lightyears , but in real time. Meaning these distants new discovered galaxies from 13B lightyears from us interract in some ways , by Entanglement with eachothers and with us. Sorry for my poor english ! Mc. Reply Bjowolf2 Bjowolf2 1 month ago Even though their spin states of the two entangled quantum particles are undefined before the measurements, they could still be in opposite states ( counter phase ) - so it's like they are connected through other (higher) dimensions, like the two ends of a twisting rope. 26 Reply 1 reply Skyhawk Heavy Skyhawk Heavy 9 days ago Are you going to cover the first ever created wormhole? Door opened to prove ER=EPR! I m glad to be alive to assist those awesome experiments. 1 Reply Kevin Malone Kevin Malone 1 month ago I've had an idea for a sci-fi story where FTL is achieved by determining a distant planets' quantum signature, and then harmonizing your ships quantum signature to the planets', there-by entangling the two signatures. Then the laws of gravitation take over, and the less massive object is instantly pulled to the more massive. Is there any scientific merit to this idea, or is it just magic? Reply 1 reply F40PH-2CAT F40PH-2CAT 13 days ago But but....trust the science! Reply Diego Marti Diego Marti 1 month ago You sir, are smart. Great episode! Reply 1 reply Patrick Sullivan Patrick Sullivan 1 month ago This question has been bothering me for a long time. So the waveform collapses and the quantum state of a particle (/wave?) is defined when measured. What is it about measurement that collapses the waveform? Is the collapse a side affect of the measurement apparatus? Or of the person knowing specific information about the quanta? To put it another way, would the waveform collapse in the same way if nobody ever examined the results of an experiment? The reason this freaks me out is that if there is a relationship between the quantum state, and the observer themselves (as opposed to the quantum state and the measurement equipment), then our very consciousness would therefore have an effect on physical world. Reply 2 replies Belathor Belathor 1 month ago while I don't fully understand every topic you share with us on thew channel I appreciate that you don't shy away from talking about the more difficult to understand subjects 7 Reply daniel rodrig daniel rodrig 1 month ago When the experiment uses the quartz crystals to divert the photons directions, could it be that the photons are absorbed in the crystal, then a new photon is released and therefore it's no longer entangled , which makes the result of the experiment invalid? Reply 1 reply Martin Lombardi Martin Lombardi 1 month ago (edited) I follow Matt since the very first day and i have to say that this is the first video i watch in this channel that leaves me very confused. I always appreciate the carefully thought information you share with us. But in this case, i am a bit uncertain if this episode nailed it... It is my understanding that bells inequality assumes non-locality and statistic independence....what has been proven is that things are non local o statistical dependent (we rule out the second one because if it were true we would be in a real mess in science)....so this has nothing to do with hidden variables. Its not a prove that there arent any hidden variables...this only proves non local effects...(if the experiments were done meassuring spin, it does not rule out other variables that are "hidden" or in other words, variables we do not know of)...Matt mentions this rules out local hidden variables very briefly so a supose the statement is in the video, yet i beleive it´s not conveyed as it should. I´m an amateur, not a expert by any means, so i could be very wrong... 1 Reply 4 replies Angel Roman Angel Roman 3 days ago It's good physics. Reply Eric Matthews Eric Matthews 1 month ago Thinking about the idea of non-local hidden variables. Could the hidden variables be related to the holographic principle? If the universe were holographic in nature, then the hidden variables could be part of that 2D surface, infinitely far away, that is storing all the information projected into the Universe. Reply 1 reply Ethiopian space science Ethiopian space science 1 month ago Well deserves 👏..... the problem of quantum entanglement was one of the biggest obstacles in our scientific journey. Reply 1 reply buttercxp draws buttercxp draws 1 month ago Oh wow! I got it!! Such an excellent explanation of quantum entanglement. Thanks 😊❤ 7 Reply 1 reply kablamoman kablamoman 1 month ago Stupid question, but one thing I’m not understanding is how the experiment rules out the spin being pre-determined by the measurement by using fast switches to change the measurement after the photons are produced. From the photon’s frame of reference, because they’re moving at the speed of light, is there even such a thing as travel time? Isn’t the concept of before and after not applicable to the photon itself? From their POV wouldn’t the polarizer be measuring them at the exact instant they were created anyway? And so, wouldn’t it be conceivable that the measurement method could still influence the result, despite the switching time delay in our meatbag frame of reference? 2 Reply 1 reply Alkeryn Alkeryn 1 month ago couldn't the photon change polarity as soon as the polarizer is known ? i mean by that point, couldn't the polarity be all possible states at once until it collapses like most QM things ? Reply Nafrost Nafrost 1 month ago 3:08 I'm now in the middle of QM 2, and pretty sure that each of those halves need to be inside a square root. Reply Yan Yan 1 month ago I love falling asleep to this man his voice is so calming Reply Bob Bob 1 month ago So if hidden variables are someday squashed. What are some current theories on how the two entangle particles exchange this information instantly or much much faster than light? Yes we can't use to for FTL communication but they can, whats their secret? Reply 1 reply Rafa Allegretti Rafa Allegretti 1 month ago I'd like to see the topic of quantum computing expanded if possible. Love the channel! 3 Reply 3 replies MarmaLloyd MarmaLloyd 1 month ago To entangle any particle it has to physicly interact. Looking at the result of that interaction it is hardly surprising that the other did the opposite. It would be more confusing if it didn't Reply 2 replies Menace312 Menace312 3 weeks ago If the photon can somehow magically know how the polarizers are set up. Then it is not a stretch to assert, that the photon knows the entire system of polarizers, quartz and numbergeneraror... 1 Reply inigmatus inigmatus 1 month ago Dear PBS Space Time: has anyone posited that time and gravity are symmetrical to the point of perhaps being the same thing caused by the same source - an illusion of the motion of matter that is merely the result of the quantum observation of two or more different planck levels of reality, as one does a flip book? 2 Reply WYS by Adam Lash WYS by Adam Lash 1 month ago This is crazy and spooky. What a time to be alive. Reply 1 reply Martin Malloy Martin Malloy 1 month ago fantastic job as always.. Reply 1 reply Watch Cat Watch Cat 1 month ago (edited) I have one of the most annoying unanswered questions about electromagnetism and the lorentz force. Knowing the orientation of two factors will determine the direction of this force (via the right hand rule and associated math). But there's the rub: What 'causes' this direction? When you consider two fields in perpendicular directions up-down and forward-backward, the left and right sides should be equal to each other and any forces produced as a result of their interaction would be additive (basically the sum of all forces in all directions) or random (either left or right from the up-down and front-back fields, with 50% odds). But this doesn't happen with the lorentz force. The direction is always the same. Is there an inherent 'spin'-like property of electrons and other electric force carrying particles, that causes a directionality in the associated magnetic field around said particle? Everywhere I searched for an answer I would always get non-answers that describe the math or how the right hand rule works, or something about convention that if you change the signs you change directions, but that doesn't explain the true origin of the asymmetry in the first place. UPDATE: ANSWER FOUND. MOVING CHARGED PARTICLES INTRINSICALLY HAVE A CIRCULAR MAGNETIC FIELD AROUND THEM, WITH THE DIRECTION OF THIS FIELD DEPENDING ON THE CHARGE. The difference in interaction with an external magnetic field between one side of the disk and the other is the direction of the Lorentz force. This does not explain /why/ this intrinsical property depends on both charge and movement direction, but that's a different question. 26 Reply 25 replies J Decker J Decker 1 month ago (edited) Entanglement isn't a white ball and black ball; nor is it a lot of white balls and black balls. It's a set of balls, of N*2 in length (so every Option1 has an Option2). these balls have a distinct number written on them, and the other ball has that number+N (if more than 2N subtract 2N) written on them; these are in pairs. At the time you open the box, you have 2N boxes, arranged in some way ahead of time such that they agree with the shape the other person is going to use (or not; as long as you know the rules). Then when you take the ball out of its box, then you count and find the right box N to put the ball in. Half of the boxes 1-N are 'up' and the other half (N+1) to 2N are 'down'. if you rotate the order of the boxes, your odds of it lining up appropriately change; at 120 degrees of separation you have a 50% chance that the box the ball ends up in is the same as the box the other guy's ball landed in; this is what bells theorem predicts, and a simulation doing this finds the same result. Reply 1 reply David Delgado David Delgado 3 weeks ago Considering the extra luminal assumption of the effect, neutrino may be the prime suspect. As the experiments don't seem to include neutrino detection, maybe? And if so, only adds to our ignorance of all its properties. Reply Alexandre Avrane Alexandre Avrane 1 month ago A question on entangled particles. Their spin is aligned in opposite directions. What would happen if one particle is moved to a location where spacetime is curved, eg. just above the event horizon of a spinning black hole ? When measured, would their spin still be opposite in 100% of cases ? Reply 8 replies q3dqopb q3dqopb 1 month ago What if during the act of measurement these particles send signals back in time, back to the moment of their entanglement? Sir Roger Penrose thinks it is possible. And if any interaction can be a measurement, does it mean that all the particles are always moving both forward and backward in time? And we just happen to notice particles moving forward in time, slower than light, because we happen to experience the ever-growing entropy. Because we move in this direction in time. If the measured particles send their back-in-time counterparts, would these counterparts be like theoretical tachyons? Could we detect them, the way some physicists hope to detect tachyons? 1 Reply 2 replies Billy Te Billy Te 1 month ago To a photon, its life is instantaneous and it travels no distance. So what does locality mean to a phonton? Can you even really consider two photons traveling in exactly opposite directions to be different particles? Perhaps there's a spooky relativity aspect to this instead of a spooky action at a distance. Also I was really hoping you would go into deBroigle-Bohm theory's treatment of entanglement, since it does contain hidden variables and concrete particle information. It also seems like it would have been an apt time to remind people that not only is Pilot Wave Theory a theory that does not respect locality, but also that standard QM also does not respect locality. Reply 1 reply Fallen Star Features Fallen Star Features 1 month ago The point at which the spin of entangled particles is determined is when the wave-function of the measurement device becomes entangled with the wave-function of the particles. It doesn't matter which particle is measured because both entangled particles share the same wave-function. The crucial point to understand is that these wave-functions don't travel through physical space-time, they propagate instantaneously throughout Configuration Space, a complex-valued domain of potentially limitless numbers of dimensions where the wave-function is defined. No information is transmitted between particles in physical space-time, all entangled particle properties derive from their entanglement with the measurement device in Configuration Space. Thus, there is no information that travels through space at any speed, hence nothing that exceeds the speed of light. What we observe in relativistic space-time is the quantum mechanical projection of events that evolve deterministically in Configuration Space. Such events appear randomized to us because the projection into space-time is probabilistic rather than deterministic. In short, the universe we observe exhibits non-local realism, exactly as demonstrated by Bell Inequality experiments. 4 Reply 2 replies samo sibella samo sibella 1 month ago Imagine being an observer trying to measure the stuff of the observed universe before it's being observed. By observing it. Lol. This is genius. Reply Damien Vasse Damien Vasse 1 month ago To rule out the problem with determinism, can we not exploit what you explained in previous videos about space-time cones formed by events? Making sure there's no common history between the creation of the entangled particules and the moment of choosing the "orientation" of the filter mechanism. Reply 2 replies Maria do Rosário Leal Maria do Rosário Leal 3 weeks ago Love this 👏👏👏 yes, I'm definitely a nerd 😃 Reply Jon Watte Jon Watte 1 month ago Have you made an episode on the a Penrose interpretation? From what I heard about it, it sounds like a plausible alternative to Copenhagen. Reply 1 reply dave miller dave miller 2 weeks ago So Hidden Variable theory and Superdeterminism are at least as unlikely as spooky action. They aren't any better. As far as I have seen, all attempts to discredit quantum theory and spooky action are born out of someone who is actively looking for any way to prove spooky action wrong because they are sure that it just can't be true. That seems to be pretty biased from the beginning. Good reason to distrust all theories born from that attitude. Reply 1 reply andola jackson andola jackson 1 month ago From phantom-matter/dark matter, to now quantum entanglement man has this last 5 years to decade been very refreshing to see. 8 Reply Trayfen O'Donnell Trayfen O'Donnell 1 month ago I have a question. Since the act of observation causes the waveform to collapse. Does that mean we are causing wave forms all over the universe to collapse using our telescopes? Are we, in effect, influencing the evolution of the universe in subtle ways by making our observations? Reply Eric Gorlin Eric Gorlin 1 month ago Entanglement isn't weird under Many-Worlds. There isn't any violation of locality or faster than light information. You just figure out whether you're in the up-down branch or the down-up branch. 1 Reply 1 reply power driller power driller 1 month ago (edited) I´m for non-locality !! The two entangled particles keep synchronized all along because they rub space-time through all their trajectories causing space-time to produce virtual photons that carry the hidden variable information for a short distance before delivering it to a next virtual photon, as a baton given in a relay run race. 1 Reply 1 reply Radosław Poprawski(YourFriendlyNeighbourhoodExcel) Radosław Poprawski(YourFriendlyNeighbourhoodExcel) 2 weeks ago What about teleportation, for a long time there were scientific issues, but with quantum computing and quantum entanglement we are closer, so the question: how exactly (deep real science) does the QE fits with teleportation? Reply 2 replies MG MG 3 weeks ago Matt , you're awesome. Reply Sam Sam 1 month ago (edited) By my count, this is the second or third time someone won the Nobel Prize for proving Einsteing wrong. The 2011 prize was won for cosmic inflation. Heisenberg's prize was not directly for his disagreements with Einstein, so that's where you could argue. Mach also proved Einstein wrong on the Steady State Model... but he never won the Nobel Prize. I think Mach holds the distinction of the only time Einstein was proved wrong without resulting in a Nobel Prize. 3 Reply Thomas Mandry Thomas Mandry 1 month ago Hello, I see another loophole not mentioned in the video: all these experiments used entangled photons. But photons proper time does not change and they are as sharing the same position as per Relativity theory. An experiment with another particle like electron would worthily dismiss this loophole. Reply MKDSLeone MKDSLeone 1 month ago Einstein didn't call entanglement "spooky action at a distance", that was him talking about "how does the wavefunction in the double slit experiment 'know' it 'collapsed' at this point on the screen and therefore won't 'collapse' somewhere else on the screen?" Very common misconception. Reply 1 reply Eric Eric 1 month ago I think a better analogy is that the particles go out and you can measure if the ball is Black or white, Green or Red , Blue or Yellow. You can’t measure more than 1 of the 3 . If you measure white the other is black when you measure the same way but if you decided to measure for GR or BY same thing. That’s what’s really spooky Vs the BW situation which is hidden variable situation. Reply 1 reply Joe Morris Bray Joe Morris Bray 1 month ago Is it possible for overall decoherent wavefunctions to have parts that are still coherent that could influence eachother? Reply 1 reply Tmb Brand Tmb Brand 1 month ago If you suggest a particular outcome to an observer, (tell them that they will observe a particular outcome), how often does the outcome correspond to the observers expectation? Reply 2 replies Basic Common Sense Basic Common Sense 1 month ago This is the same with entangled (married) people. Whenever I make a decision, my wife instantaneously decides the opposite! 3 Reply Sangmoo Hwang Sangmoo Hwang 1 month ago How do you prove the information of you opening a box is transmitted instantly, with the speed infinitely faster than the light speed, to the other box? Do you actually measure time that takes for the transmission? Reply 1 reply Funding Zen Funding Zen 1 month ago Correct me if I am wrong, but you shouldn’t be able to keep particle entangled from earth to the moon. In my mind, the resonance frequency with respect to space time will differ based on both the gravity/time of the moon vs earth as well as time dilation cause by traveling through space/time. This should pull the two particles’ resonance out of symmetry. Just seems like if it remained entangled, then Reply N.S.Y.Abeygunawardhana N.S.Y.Abeygunawardhana 1 month ago Day by day,ur videos are getting better..! Reply 1 reply Christian Domenech Christian Domenech 1 month ago “Now imagine these are QUANTUM balls with entangled quantum colors” Yeah, ok thanks Einstein. Reply Aldo F Aldo F 1 month ago An idea, what if there are a quantum field for this entanglement information to travel faster than photons and this field has gravity (dark matter) Reply 1 reply Damiaan van der Heijde Damiaan van der Heijde 1 month ago I always thought about it this way. You have one black and one white ball. You put each in a box and mix them up. Send one to the moon and the other stays with you. To know, without opening the box, the color of the ball you have, someone needs to open the box on the moon and send you that information. It’s not about knowing what’s going on elsewhere that matters. It’s about knowing what’s going on in your own frame of reference that matters. 5 Reply 1 reply Dextrous Kid Dextrous Kid 4 weeks ago Will enough development with quantum experiments allow us to escape from the influence of space-time fabric, gravity and constraints of mass outside quantum? Reply Cat Woods Cat Woods 1 month ago If opening quantum box 1 results in entangled box 2 far away being forced into the opposite state, couldn't that convey information faster than the speed of light? Maybe not as well as Ursula Le Guin's "ansible," but still, you could give an instantaneous signal to people in a faraway colony, couldn't you? I saw a Leonard Susskind lecture where he said no, information can never travel faster than light, but I don't understand why this wouldn't work. (Except the practical problem of having to send the entangled box with the colonists in the first place. Still seems to me you'd be able to send one off/on type of signal later.) 1 Reply 3 replies Cat I Cat I 2 weeks ago Won!!! Reply Patrick Pease Patrick Pease 1 month ago I dont get how einstein didn't grasp "spooky action at a distance" photons do not experience time because of their relativistic speed. As far as the photon is concerned it is enormously long and connected to both it's starting point and its ending point simultaneously. If this is true, and its twin particle is also experiencing the same effect then the particles have never lost contact and can influence each other until one or both are destroyed. Im clearly a lay person so please don't abuse me for how dumb this sounds if im wrong 1 Reply James Ruscheinski James Ruscheinski 1 month ago (edited) why does observing quantum particle / state cause the wave function / probability to update from 50/50 to 100%? Reply Karla Karla 1 month ago Congratulations Mr. Quantum entanglement on winning the nobel prize 3 Reply The Math Tutor The Math Tutor 1 month ago This is why we like Physics. Reply Lucca Q Lucca Q 1 month ago In 100 years its going to be embarrassing how wrong we’ve been about our understanding of quantum mechanics. Reply Like icecream Like icecream 1 month ago I don't think quantum particles "travel" in a sense people think they do ie. spacetime. So when they observe them in different positions correlating instantaneously they're not really in two different positions, they're in a state of omnipresence. Reply buttegowda buttegowda 4 weeks ago (edited) The real dilemma to answer about the experiment is : If ball on earth chooses to be 'White', and when Simultaneous an experiment is made on moon to find out the color is an impossibility to begin with . If I open the box and see the ball to be white, it does not prove that at that time the ball on moon is black. It is just as good as state 'not known' which is fine. In quantum mechanics, each and everything is a possibility, not a certainty Reply Graeme Fern Graeme Fern 1 month ago Quantum entanglement melts my brain. Reply MetaSamsara ∞ MetaSamsara ∞ 1 month ago (edited) Regarding seeing the Lagrangian model laid out in full I personally can't read it as an operation, but i very enjoy when you dive into the logic of why this variable is combined with that variable, vectored, etc. Don't need to understand the full background to explain that we calculate speed as distance*velocity, etc, and it gets us close to really understanding the inner workings of the theories without having to grasp them in their entirety if you focus on one or two bits of it at a time. that's personally how i looked up shrodinger, and started looking into the meaning of its symbols outside of the math, the logic of their workings, and i found a lot of flaws that im not scientific enough to fully expose on my own, but i still "*know*" better. cognition can take a lot of forms, scientific rigor isn't what kept life alive on earth you feel? most humans dont even begin to grasp which extent. 6 Reply Tempestive Tempestive 1 month ago I think challenging the status quo will always be an important tool as a species. However, how to question has some depth to it - there are bettet and worse ways, and it's not innate knowledge. Reply 1 reply John Bauer John Bauer 1 month ago So answer me this Batman, if we observe one of the entangled pair, does the other stay in a superposition until observed or does it change before? Is there a way to test this? Sort of measure without looking?🤔 1 Reply 1 reply Jack Martin Jack Martin 1 month ago What if everything exists in every single location and every variable possibility and it is just the observer that changes its vibration and electrical charge to observe what they choose? Reply Kim Jones Kim Jones 1 month ago What if the first guy to see inside the box, then close it back up again, without telling anybody what he saw. Then, someone else opens the box. Is he going to see the same thing the first guy saw? Or, since he is unaware of which object is in the box, is it possible that he would see something different? Reply 3 replies Khilorn Khilorn 1 month ago You just made me understand wave function equations in 3 minutes holy crap Reply 1 reply clearnightsky clearnightsky 1 month ago I think Einstein made that mistake because he imagined (as we all did) that one particle must somehow influence the other. It seems this is no longer the case. 4 Reply Азис Мразиш Азис Мразиш 2 weeks ago If two particles can be made entangled, does it mean that any particle has its entangled counterpart in universe? Reply 1 reply Daniel McKim Daniel McKim 1 month ago If you have two entangled electrons, one spin up the other spin down. You measure lateral spin of the down election, can this change the up spin state of the other electron? Reply Narfanator Narfanator 1 month ago (edited) It's been awhile since scientific proof has left me in awe; it could be its explanation though ;-) Reply 1 reply Dakota Dalton Dakota Dalton 1 month ago Could we appeal to a higher dimension for quantum entanglement? Light can only circumnavigate the globe in a given amount of time, but a neutrino could pass through it in a smaller amount of time, seeming to travel FTL from the perspective of someone stuck on the surface who could not perceive the additional dimension. I’m curious if this is a viable answer to non-locality. Reply 2 replies Milos Djuric Milos Djuric 1 month ago (edited) I would really appreciate answer to the next question: If we agree that speed of causality applies on this entangled photons (c), we can tell that the event of creating two entangled photons for each measuring instrument happens when it reaches boundaries of this instrument. So there is no way to say that someone changed the angle of the instrument BEFORE the entangled photon was created (!?) Please correct me if I'm wrong, but doesn't this seriously endangers the very methodology of the experiment? The event of creation of the entangled photon occurs for a point A (1.measuring instrument) as a reference point "after" the speed of causality c passes the distance between the source and measuring instrument. Reply 1 reply Anders Anders 1 month ago Great Nobel Prize choice! Quantum entanglement shows some kind of nonlocal connection in the universe. And actually, reality must as I see it be one wholeness at the most fundamental level. 3 Reply Adam Reynolds Adam Reynolds 1 month ago can you entangle two particles and measure ones momentum and the others position? breaking the uncertanty principle? 1 Reply Kareza Alonso Kareza Alonso 3 weeks ago If quantum computers were used in any of these calculations and simulations, does that mean the results were biased? Reply Dan Rossi Dan Rossi 1 month ago (edited) Quantum internet coming to us sooner than we think. Which requires photonics switching and fibre. They already experimented teleporting matter over fibre. Reply Gryphon Connor Gryphon Connor 1 month ago My question about spooky action and entanglement is where do we see it in nature? If the universe is full of entangled particles that don't seem to need to obey causality, what impact does that have on our universe? In other words what else do we observe in nature that couldn't be true if spooky action at a distance didn't occur? Reply 2 replies Ronald Jordan Ronald Jordan 1 month ago I love this channel and I love my "The heat death of the universe is coming" t-shirt 😎 Reply 1 reply Gabbie Wolf Gabbie Wolf 1 month ago You're right that the infinities don't belong there. I'm currently studying the prerequisite maths to understand QFT, but from what I've read there's a formulation of perturbative QFT that doesn't require any hand cancellation of infinities, formal deformation quantization 5 Reply rfvtgbzhn rfvtgbzhn 3 weeks ago Non-local hidden variables are not really a loophole. Bell's inequalities where always just described as a test for local hidden variables, not for hidden variables in general. It can be proven that non-local hidden variables can in general not be ruled out within the known logical frame of physics. However non-local hidden variables are already non-classical. Reply Afilon Afilon 1 month ago Speaking of Einstein and Quantum Entanglement... is it possible that quantum entanglement and Einstein-Rosen bridges are somehow connected? Reply 1 reply William Lyons William Lyons 1 month ago There is a new realm of physics that gets confused with quantum entanglement. It deals with instantaneous transport. it also needs not to be confused with quantum transport; again different. Reply Lim zah Lim zah 1 month ago Awesome video ! So happy to announce that I have gained financial freedom by investing in digital currency. Now I know that multi creation of various streams of income is the ideal Principle for financial sustainability. 18 Reply 25 replies Hainet Korea Corporation Hainet Korea Corporation 1 month ago Congratulations on the Nobel Prize in Physics and Quantum Communication. Quantum biology. The nine colors of physics, the coherence of the quantum colors of living creatures in quantum biology and the colors of quantum coherence became the decisive evidence that announced the birth of life on Earth. In other words, the origin of life is chemical synthesis, change and evolution. Marine algae (green seaweed) Cellulose is a living cell. 1 Reply 1 reply 0mn1vore 0mn1vore 1 month ago My condolences to any of Aleksander'd friends and family who might be watching. This was a really nice way to send him off. 4 Reply Mark Campbell Mark Campbell 1 month ago An electron emerging from the halogen nearby is still spooky. Reply Chris Dewayne Chris Dewayne 3 weeks ago So what happens if you make a measurement of both ate the exact same time!? Reply Robert S. Robert S. 7 days ago Waaaa scientists.. they showed who they are in the past 3 years. Reply Norwegian Smores Norwegian Smores 1 month ago thanks to quantum entanglement we have the theoretical basics for instant transfer of digital communication. one could "quantum skype" someone on the other side of the universe with zero delay assuming you could keep it entangled Reply 1 reply lal senrath lal senrath 1 month ago Being humans we try to enforce our perception abilities outside us, that is environment around us. If you think deeply enough, simple thing like distance between two objects, or monument of objects is mind blowingly complicatedl. Reply 1 reply Noah Spurrier Noah Spurrier 1 month ago So the programmer of the universe uses global variables? Very hard to debug that kind of code. 15 Reply 6 replies gapster77 gapster77 1 month ago Potentially could one particle be manipulated in a set manner, to have the other move in respect to it, on a whim? Could manipulating the movement of one in a coded way be directly decipherable in the movements of the other, and if so could this be the basis for instantaneous communication across unlimited distances? Could this be a way of communication that any crafts leaving Earth, to somewhere else within our own system, or to another system, could use in the future? Reply 2 replies Bob nob Bob nob 1 month ago That's the first time I've done the survey. Didn't realize PBS did so many other things Reply 1 reply Aku Aku 4 days ago We are also entangle to our future self. Reply Bryan Bartlett Bryan Bartlett 1 month ago Slightly off topic, but I got a burning question. If we take as fact that Gravity travels at the speed of Causality (the speed of light in a vacuum) and that for an object to be able to affect us we have to be in its future or past light cone (where speed of causality marks the borders) Does this mean that the gravitational effect from one object to another is not based on where the objects are, but where they were? (Earth is pulled to where the sun WAS 8 min ago) Reply 6 replies Joseph Shawa Joseph Shawa 1 month ago (edited) Things only happen one way. At least in my experience. That being the case, it seems evident that everything would, at least mathematically, be all part of one equation. It's so simple I can't see it any other way.... The results are already in. It only happens one way and here it is in all it's super deterministic glory. Reply 1 reply Geodesic Interpolation Geodesic Interpolation 1 month ago (edited) This is awesome work. Once again PBS spacetime knocks it out of the park with explaining things. 5 Reply Dirayya Dirayya 1 month ago Wait, the fact that we turn the vibration switch on or off. Even when we create a randomized switch, don’t we create a function to create random measurements, which itself is a measurable thing. I wonder, the whole thing of superposition looks like a self-typewriter of the universe, accumulating all information happening in the universe. The whole idea of measuring distorts our measurements because it this information is also simultaneously recorded into the universe. Aren’t we just breaking the wall to find another one beyond? Reply Cross Platform Adventures Cross Platform Adventures 1 month ago So then non-local hidden variables could exist? Is that the "wave function of the universe" they talked about in the Andromeda TV show? Reply 2 replies Bhadra Parekh Bhadra Parekh 1 month ago Watched many videos on this topic but this was the one I was looking for. Reply 1 reply kyzercube _ kyzercube _ 1 month ago Wow! I actually thought Clauser already won the Nobel for his work on entanglement years ago! All 3 of them are overdue imho. GJ! Reply 1 reply Thomas Poczontek Thomas Poczontek 12 days ago Mat you are a legend 1 Reply Philip Murphy Philip Murphy 1 month ago Congratulations to Quantum Entanglement on winning the Nobel Prize at least. 41 Reply 1 reply Jon Tucker Jon Tucker 1 month ago Frustrating thing about this video is the Nobel recipients here absolutely didn’t “prove entanglement” to be real, not in the slightest. They proved that our universe is non-local. That’s a subtle, but extremely important difference. The result actually supports austere QM theories (many-worlds). Reply 1 reply Clark Kent Clark Kent 1 month ago 10:10 but cant electricity ALSO not move faster than light? if a photon gets created, and then after the switch is flipped, could the switch being flipped influence the photons since this will lead to the electricity vibrating the crystal ? (determinism) since if a photon is created and the polorize is rotated then it automatically knows what rotation the polorize will be at (determinism) Reply 1 reply ispirovjr ispirovjr 1 month ago Is it just me or is there a typo on 3:10? The normalization constants should be 1/sqrt(2), because their squares should add up to 1. I might be wrong. 1 Reply 1 reply PMgn844 PMgn844 1 month ago You have broken my brain. Again. This one will need to be watched a couple of time to get it. So Feynmann didn't want to move outside the fixed paradigm? Looks like Thomas Kuhn's description of how science advances is still pretty accurate! Reply 1 reply Hyil Poulle Hyil Poulle 4 weeks ago By non-locality do you mean that we may be living in a simulation and the variables are living in some computer's memory? Reply Andre Almeida Andre Almeida 1 month ago (edited) Could it be that information actually "travels back in time"? In our time at least. If a sentient photon does not perceive time from it's perspective, it already "knows" everything in it's existence from creation to annihilation. It is ourselves that perceive it travelling through our time, so the concept of decision is completely ours, the photon simply exists. 3 Reply 2 replies Antrix Pathak Antrix Pathak 1 month ago How are two particles entangled in the first place? How do we determine that the particles which we are entangling are not already entangled with some other paricles? Reply 1 reply GeneticJen GeneticJen 1 month ago It still feels like a major misunderstanding when people say Einstein’s “spooky action at a distance” refers to entanglement but everyone seems to do it. I’m not convinced he couldn’t believe in correlations. Reply 2 replies Hedgpig Hedgpig 1 month ago Somehow I missed the "Why" in the title first time I read it, and thought nobody was sure if it won the prize because they couldn't observe it Reply 1 reply Kan Solo Kan Solo 1 month ago It's funny how your videos start out with high school level understanding and then ramp up to Ph.D.-level language. Halfway through I'm like wtf! Reply 1 reply David Rojas David Rojas 8 days ago Thank you Reply John Mullane John Mullane 1 month ago Can’t believe Feynman said no. I thought he was more open minded than that 10 Reply 3 replies Johnny Wagers Johnny Wagers 1 month ago If all of this pans out, we will travel beyond all, we will know all! Whether it be bad or good. There will be no speed limit nor boundary! Speed time space! It could I’ll be irrelevant one day! I love this stuff! lol Reply 1 reply Cmdr Bacid Cmdr Bacid 1 month ago Can quantum entanglement be involved in the mystery behind the double-slit experiment? Reply 1 reply Lauren Doe Lauren Doe 1 month ago (edited) To me, superdeterminism means that absolutely everything in this (and every other) universe has already been decided. We are just actors in a pre-written play; there is no free will, there is no such concept as "random." Unpredictable, yes; random, no. Reply 1 reply maxpower252 maxpower252 1 month ago Then there is hope for the theoretical physicists like Maldacena and those guys to win this Prize… Reply 1 reply A A 1 month ago (edited) How does entanglement explain the time shifting of a clock as it moves through a gravitational wave? And This would imply that everything has a duplicate negative clone equally distanced from their point of origin. This makes the universe look like a mandelbrot illustration from the outside. Kind of validates the old theory of duality too. It's also implying that for a person to carry the box to the moon there will have to be another person carrying it to an inverse moon if the pair are linked, or are humans just built different? 1 Reply Jose Martinez Jose Martinez 1 month ago (edited) Matt, isn’t there a problem with using a random number generator to randomize the polarizer position, considering that true randomness is impossible? Or am I missing something? 3 Reply 5 replies Michael Jones Michael Jones 1 month ago Assuming the audience lives in the same universe as I do I can accesss that the state of matter actually has a 'wet state' and a 'dry state' simultaneously yet when it quantumfies its acted upon by anti-matter of each of these states which will draw down its marveleous state to a hour glass effect to then emerge into the opposite states of dry-wet to wet-dry matter but while this is not changing its characteristics it is simply repositioning matter in a time state and this can occur a multitude of times which also can produce more matter as time proceeds so that in the long haul what is observed is not a simple element but rather a multitude of elements that can then reposition themselves as well to rematrix a mass. If you can see this occur in space you might think that the explosion out your portal of that planet has been infleunced by this quantum reaction. Also akin to observe that a slate stone can become entrapped in a water fall on the boottom of a pond and forced to rotate thus creating a hole at the rock bottom and the slate rock composition will enter a quantum spin to its interior creating crystalline structures in its center core over years of rotation and heat transfer never achieving a melt down temperature and maintaining its state of matter except for the c4rystalline structure that grows inside this slate stone that is discovered by someone whom can see holes at trhe bottom of the water fall in the bedrock and a slate rock in the bottom now not rotating because the stream on water has decreased to zero but to retrieve the rock will take some engineering feat since there is more than one hole to deal with. We live here, we observe here and we can breath withy honor that we knoow thee thibngs do happen in nature without mankind causing them to occur as it will always be in space as well. Thanks, I hope you have envisioned this phenomena mentally, I could show you the location specifically. These stones wil become as shaped as a UFO not perfectly a round ball, note that slate does not have crystal in its center normally and it is not a dinosaur egg. Reply Stephen DeVore sadsongsishere Stephen DeVore sadsongsishere 1 month ago (edited) If quantum entanglement is real across great distances, then it seems that there's something seriously missing in our understanding of how that could be possible: What exactly is it that is "communicating" or entangling faster than the speed of light? And, What can we do with that? (And for the many: Which videos can we watch to make all of this crystal clear to us, without it sounding like nonsense or fiction?) 1 Reply 1 reply Tan Chun Aun Tan Chun Aun 1 month ago I think the wave function equation at time 3:13 has missing square root Reply Din Noel Din Noel 1 month ago What evidence do we have photons maintains their original characteristics (spin in this case) after going through crystal (or air for that matter) ? especially when there are additional photons hitting crystals at the same time (the ones that arrive with electricity to control path of the tested photons) ? Any, no matter how small, change in photon spin induced by other elements would violate Bell inequality and produce entanglement look-alike Reply 1 reply HenryManson HenryManson 1 month ago True question is: could we "uncollapse" a wavefunction & use the same again?! how would we know its not a new one, but the same?! Reply Down The Rabbit Hole Down The Rabbit Hole 1 month ago I'm a little surprised. Although I can't at the moment remember WHICH video it was, I can say I've seen at least one that did a MUCH better job of describing the experimental setups that were used by these prizewinners. I expected to see such information in this video, but the details of the actual experiments were absent here. 3 Reply RustyBoysGaming RustyBoysGaming 3 weeks ago quantum entanglement could lead to an infinite range communicator based on binary or a morse code like system Reply 1 reply Ryan Jerles Ryan Jerles 1 month ago Survey done, ty for all the content over the years Reply 1 reply Brian Parnell Brian Parnell 1 month ago Please Help With This Question If Able; It seems that in QM the terms "know" and "choose" are used quite often. To my simple mind these seem like things exclusive to living creatures. Rocks don't "know". Photons don't "choose". We talk about a possible exchange of information at TSOL which might violate Causality but I have to ask...What information is being transmitted/sent/divined between the two entangled items in question? What form is it in? What method is used to encode/decode or make sense of the data by a particle without the capabilities of discernment. Basically, how does it know what it's supposed to know? If we can't say what is passing between the two, how it's being done, and how these "choices" are made then that all seems to support the Hidden Variable Theory. Reply ooPapa Smurfxx ooPapa Smurfxx 1 month ago (edited) PLEASE make a video on Non-Local hidden variables!!🙏 2 Reply 1 reply Tim Bucks Tim Bucks 1 month ago As a layman, I have always intuitively thought that Quantum Entanglement makes sense if you assume that reality is more like a Mandelbrot set: all things are repeating patterns of basic reality, because the idea of separateness of physical objects, is an illusion. We have 'spooky action at a distance' because objects are the same thing. Literally. It's an illusion to think we can separate ourselves from other people, from the universe. No need to violate the speed of light, because not only is time universal, meaning time is the same everywhere. So is localism...everything is literally part of the same locality. No need to go anywhere, worry about the speed of light between objects because all objects are one thing. This means all information exists everywhere, equally. What is information? Numbers. This means numbers are all equal. Every number, in some way, is the same as every other number. My basic formula for reality: 1 = 0 = infinity If you shoot a light into space, the space is curved, it will return to the same spot, because it never left. It's an illusion to think it left. Locality and separateness of objects is an illusion. All distances are the same, since distance is an illusion. All times are the same, since time is an illusion. How are times and distance measured? By numbers. This means all numbers are the same. This means: 14 = 0 = 6 = 3 = 1 trillion etc. It's the same time, everywhere. There is no past or future. Only now. Consciousness and life create an illusion of separateness. We are born, the miracle of life is convincing us we are separate from reality. We are not. Reply 1 reply Gabriel Velasco Gabriel Velasco 1 month ago I believe in a "hyperdeterministic" block universe where the entire past and future are fully realized and always exist simultaneously. It is our consciousness that is traveling through the time dimension in this static, fully realized, fully existent "block" universe. 3 Reply 1 reply Chris S. Chris S. 1 month ago Got to wonder, based on the episode on 13.01.2016 , would this experiment hold if the emitter were in a tall building shooting from the ground floor to the roof (past to future) or vice versa on the roof (future toward past)? Was this experiment always carried out horizontally? An explanation of the 2022 Physics Nobel Prize Adi Armoni 140 subscribers Subscribe 241 Share 19,891 views Premiered Oct 7, 2022 The theoretical background of the 2022 physics Nobel prize, awarded to Aspect, Clauser, Zeilinger. Discussion of the EPR gedanken experiment and a detailed discussion of Bell inequality. 48 Comments rongmaw lin Add a comment... Suffering For Pleasure Suffering For Pleasure 2 months ago We need more youtube teachers like you. 2 Reply Adi Armoni · 1 reply Airi Airi 9 days ago A brilliant piece of content. Thank you for the explanation! 2 Reply TheWiseApe TheWiseApe 2 months ago (edited) Amazingly clear explanation- it was only through this video, after watching and reading up on this for the past 2 days, that I feel like I'm getting a grasp on what was going on with the science behind this Nobel Prize. I never thought that my semester of gen chem learning about filling in electron orbitals would help me understand this years later! 5 Reply Adi Armoni · 1 reply Chiu Hung Wong Chiu Hung Wong 2 months ago Thank you sir. After many days of self learning I finally grasp the idea with help of this video. Thank you so much. 2 Reply Pattreeya Tanisaro Pattreeya Tanisaro 2 months ago Thank you sir. I got a better idea of Bell Inequality and its contradiction now. 3 Reply hasan alatrash hasan alatrash 2 months ago Great video.. but What about the communication in between two particles at a distance? does that mean the information do spread faster than the speed of light? 3 Reply Adi Armoni · 2 replies Sumangla Kapoor Sumangla Kapoor 2 months ago Thank you so much! Reply Ultimate Seeker Ultimate Seeker 2 months ago Thanks sir🙏🙏 Reply Йордан Панталеев Йордан Панталеев 7 days ago (edited) I'm probably watching 5th video about this and not a single video or in the comments I got an answer to my question. Let me explain my question. Supposedly local hidden variables theory is incorrect. Let's say we have Alice And Bob measure one of those particles. Bob is much closer to the source, so he gets his measurement first. He knows what Alice will get, therefore the particle that is still racing towards Alice knows that as well. And it will know it all the way until it reaches Alice's detector. Now the question: Where the particle keeps that information if there are no local hidden variables? Do they suddenly appear? Or the information is not local, but instead available everywhere? Reply 1 reply Peter Eirich Peter Eirich 2 months ago This is a brilliant presentation. The handwriting, however, is first grade level. 4 Reply 1 reply Karissa D Karissa D 2 months ago Very nice video too💓~~~>💓°•○☆💕 1 Reply Juan Pachel Juan Pachel 2 months ago and thus nature is probabilistic 1 Reply RoboticusMusic RoboticusMusic 1 month ago It sounds like to me spin isn't something that happens like rotating the hand of a clock, rather the clock is more like a potato chip shape. This explains the nonlinearity "S" curve, no? 1 Reply 2 replies Odin Odin 4 hours ago Sorry but why do we assume the two spins are related Reply Joseph Harris Joseph Harris 2 weeks ago What are your opinions of the vast disagreements on this measurement / entanglement debate?? It's not lost on me why this would appear that the universe is probabilistic. But my intuition tells me that this experiment rather reveals that a "constant" or, The Universe, is intrinsically aware of quantum effect outcomes, in a way that disregards the speed of light, and that the wave function rather acts as an approximation of what's perhaps an unknown constant. To me, I feel particle physicists are incorrectly seasoning this observation with "multiverse" theories and "faster than light communication" because they can not reconcile the these observations. In my mind, what's being "observed" is that two entangled particles seem to know where to go, in a way that is congruent regardless of speed. That also does not violate the other constants which have been very well proven at this point. Also I give you big credit for pointing out that Quantum Mechanics is moreso an apparatus for approximating reality, and that Bells inequality only points out that the characteristics are not yet well confirmed. I feel it's important to note that Theorists may using math to reconcile our observations rather than using math to make a prediction. I tend to agree with Einstein in that there is no 'spooky action' between particles, but rather that the experiment is revealing that there is a chosen outcome preordained by nature or an unknown constant. In my mind, these experiments and observations seem to verify deterministic nature, and I feel that the wave function equation has unfortunately become reliable enough for Physicists to believe that it's how nature functions. It is actually somewhat frustrating that we observe 1 outcome when measuring, and a universe full of matter, yet Quantum Theory predicts undefined characteristics & 50/50 matter/antimatter ratio but they resist not admitting that there is a degree of both inaccuracy, and incompleteness, in Quantum Theory. Sorry for all the venting, I hope you see this but if it's too much to reply to I can't blame you! Happy holidays! Reply Lauren Thomas Lauren Thomas 2 months ago 69 likes. That makes sense. Ya know, yin/yang. 🤷‍♀️😊 1 Reply Joel D Joel D 1 month ago there are of course 11 dimensions. to talk x and y, is of course crazy Reply Karissa D Karissa D 2 months ago Random : Who remembers that episode of Criminal Minds with the Rosen Bridge joke?! Huh,??huh??~~~~>💓°•○☆💕Rubberbabybuggybumpers~ Reply crazieeez crazieeez 2 months ago Communication is faster than the speed of light. It is the intricate correlation between the entangled particles that has faster than light communication. There is a physical process that goes on. We all know space time is subjected to bending, curving, twisting, and all sort of geometric configuration. I think Suskind is working on a paper describing how wormhole work at subatomic level. Saying Einstein is wrong is like saying Newton is wrong. Whatever new theory that comes out will need to satisfy Einstein General Relativity as a special case for large scale object and satisfy quantum mechanics at the small scale object. 2 Reply 10 replies Tom Edward Tom Edward 2 months ago Little suggestion for viewers - run video at 1.5 x speed, talking was too slow for me. Reply Blackbeard2003 Blackbeard2003 2 months ago (edited) EPR was not disproven by Bell. J.S.Bell made a mistaken assumption. Here is why: In the video at 17:04, P(2*) is NOT EQUAL to 2P*, (*=theta), this assumes 2 dimensional thinking, and our world is NOT 2 dimensional. Actually, P(*) is the probability of the axis of spin being oriented such that it falls into the angle * when observed in the direction of travel. In other words, the 2 dimensional derivative of a multi-dimensional vector. None of this has anything to do with "hidden variables" or "superposition". It is simple multi- dimensional math, and misunderstanding by people thinking in 2 dimensions. Bad assumptions, not "spooky action". Bell did not disprove EPR, he just mistakenly misled the physic community. Bell's Inequality Debunked! Bell's Inequality DrPhysicsA 310K subscribers Subscribe 3.7K Share 294K views 10 years ago Quantum Mechanics A basic introduction to Bell's Inequality which shows that there cannot be hidden variables (a form of inbuilt DNA), as postulated by EPR, to explain how entangled particles behave. 785 Comments rongmaw lin Add a comment... Jose Moreno Jose Moreno 2 months ago The only explanation that allowed me to finally understand in what way Bell's inequality enlightened modern physics. Real gratitude. 7 Reply Khyatee Atolia Khyatee Atolia 4 months ago Hello Sir, Thank you so much for this explanation. I have searched a lot of sources but no one has explained it in the concise and clear manner that you have. I felt like the conclusion was absolutely a natural consequence of your amazingly well laid arguments. You are a great teacher. Thank you for igniting more curiosity in me about physics and the strange nature of quantum particles. Keep doing your amazing work sir!!! 9 Reply AKASH ARUN AKASH ARUN 2 years ago A big thank you...i was struggling to grasp bell inequality and its role to eliminate the hidden variables theory. Beautiful and lucid explanation👍 12 Reply Arnold Kim Arnold Kim 9 years ago Thanks for making more clear what Bell's Theorem is all about. I've been struggling to understand what this is about for some time. Even though this is not a rigorous formalized presentation, I now can try to take on the more technical discussions with much more ease. Thank you once again. 4 Reply PJ PJ 2 months ago This was an extremely clear and unambiguous explanation, thank you! 2 Reply Michelle Spremich Michelle Spremich 3 years ago Thank you so much. I have been trying to understand Bell's Inequality for awhile outside of a formal academic setting). This is by far the best explanation especially for a non-scientist! I appreciate you! 16 Reply 3 replies Rafael Nogueira Rafael Nogueira 2 years ago OMG! Thank you soooo much! I watched so many videos and couldn't understand why the hidden information proposition were not the right one. Such a good video! 2 Reply Galahad Garza Galahad Garza 2 years ago Thank you for the excellent explanation of Bell’s Inequality and how it ostensibly proves that there are no hidden variables—as the EPR Paradox asserts. 7 Reply windlesSpice windlesSpice 4 years ago Bravo. A great explanation even without fancy graphics. Thank you. 2 Reply XTheDentist XTheDentist 6 years ago (edited) Hi, thanks for these great videos on physics very much appreciated. Now I've been trying to figure out what entanglement is for some time now & i think I've made some progress so if someone can help me out, just please dont bite my head off :) So, starting with the double slit experiment, a single slit produces random dots as would be expected of particle behavior whereas a double slit produces an interference pattern suggesting wave-like behavior..ok fine. Now, placing a detector at the slits, the interference pattern disappears & QM theory says that the "wave function" collapses as a result of the measurement effectively eliminating the superposed states etc. Now, if we generate a pair of entangled photons, A & B, and measure some property of A along an axis we shall have random results as would be expected, but when we measure its entangled partner we have 100% correlation with A (ie NOT random) implying that measuring photon A, and thereby collapsing its wave-function to a definite state, causes the wave-function of its partner, B, to ALSO collapse presumably instantaneously. According to Bell experiments all local hidden variable theories have been rendered useless, we have Bohmian non-local hidden variable theories which work as a valid interpretation but doesnt really advance our knowledge of QM. Now I have to ask this not because I think its correct but because the fact that im thinking it means theres something im not understanding. Why isnt the process of generating entangled particles the problem? I mean, during the process they simply acquire correlated polarization or whatever other property, why does there need to be this mysterious hidden variable or "pilot wave" or faster-than-light communication? Is there some experiments that have been performed that rule this possibility out even if we couldnt observe this process directly to tell for sure? Are there natural processes that produce entanglement? How do we know for sure that the entangled pair have not already experienced state-collapse as a result of whatever produces entanglement? 6 Reply 1 reply Ozymandius G Ozymandius G 8 years ago This is a GREAT presentation of the material. It makes the main points accessible to non-mathematicians. I do have one question - what if all of the 8 rules are not feasible or, more realistically, do not apply to the photons in equal percentages? That would explain why the measured outcome is less than 1/3 2 Reply creighton jones creighton jones 6 years ago Has it been experimentally demonstrated/determined that, for an individual photon, the three possible polarization states that you chose for example each have equal probability of being measured? In other words, are individually emitted photons statistically weighted towards having a particular direction of polarization or another? Is that important to know for this example you have given? With that said, is it correct to say that in QM experiments and theory, that a single quantum element will have a different probability of producing a particular measurement than it will were it to be measured as part of a conjugate pair whose partner has been measured? 5 Reply liudas5377 liudas5377 2 years ago Fantastic lecture. Great, easy to understand explanation... 2 Reply arlie arlie 6 years ago Thank you very much for this video. Very well explained. Bravo. 2 Reply Leonhard Doerflinger Leonhard Doerflinger 4 weeks ago 2022 here... and this is finally the one video that lets me understand what this year's Nobel prize was all about. DrPhysicsA has always been the best. Brought me through a third of my exams as well. Reply gk89 gk89 9 years ago Nice video! I still have a hard time understanding the Kochen-Specker addition to Bell's theorem. If you take any request for video's I would like to see you explain the KS theorem. 1 Reply Marcio Pocciotti Marcio Pocciotti 10 years ago Very Nice Video. Although there were some "bumps" on the road, still it was very clear. The best one I found on the web to explain well Bell's inequality. Thanks. Reply Exalted Citharode Exalted Citharode 1 year ago (edited) Crystal clear explanation. Thank you. 1 Reply Juan Green Juan Green 9 years ago Thanks this is a very clear explanation, I think I'm beginning to understand it, must watch again. 1 Reply Sherlock Holmes lives. Sherlock Holmes lives. 3 years ago Thanks for these truly intelligent lectures, Phil! I love your knowledge but I don't understand the vast majority of your information! I wonder, just out of curiosity, if you know also Goethe's 'Theory of Colours', I think I can grasp that. Although sometimes it seems my mind is so slow I only understand in science Plato's 'Wax Tablet Hypothesis' and Aristotle's 'Theory of Everything'. Lol! 3 Reply EnDotter EnDotter 6 years ago Hey! I got a question since i am "a bit" confused. When A and B are doing experiments on entangled photons using random slits (/, \ and |). How come can the 1st line of the table be all true (T)? If one photon can pass through |, it means other one will certainly pass through | and maybe pass through / or \. I think i understood this enough to say it's fine. On the other hand if one photon passes through / i can for sure say other one cannot pass through \ since its 90º rotation and that it could pass through |. Why is there a given case that A and B could register same result no matter which combination they choose? If my reasoning is right, will it shift the probability of getting the same result to be greater or lower than 1/3? 1 Reply ANANT RED ANANT RED 9 years ago I think I understand it now. For any *one* of the eight decision schemes (hidden variable) of the photon pair, the chance of (A and B) getting the same outcome is at least 1/3, since 6 of those schemes give a chance of 1/3 and the other 2 give a chance of 1. I was calculating the probability over *all* the combinations, which is the average (1/3 * 6 + 1 * 2)/8 = 1/2. Thanks. 1 Reply Shayne Murray Shayne Murray 7 years ago Thank You Dr Physics I was struggling to follow the written description of Bell's Inequality and until your most enlightening video! 3 Reply Rika Bernar Rika Bernar 2 months ago This's amazing. Love it so much. Reply Peter B Peter B 3 years ago A brave attempt. Another good explanation can be found in Brian Greens book: Fabric Of The Cosmos. One questions what percentage of results differ from predicted results, further on what distance and expected time variables, factoring in the limits of accurate measurement and possibilities to improve on this (at least theoretically!) 1 Reply Krish Rao Krish Rao 2 months ago Wow, what an explanation! Thank you very much. Reply Voss Malone Voss Malone 4 years ago Thanks Doc - easily the clearest explanation on the web - and I have spent an afternoon searching - now I might go back to Prof Susskind (who was not so clear) Reply Matt Bruce Matt Bruce 7 years ago Thank You, this is the best video on Bell's Inequality I have found so far! Reply Alberto Prats Rodríguez Alberto Prats Rodríguez 4 years ago Great explanation! Thanks! 1 Reply DrPhysicsA DrPhysicsA 9 years ago I shall do another video on this shortly during the series on quantum mechanics concepts. In essence, Bob can certainly get a result from such a measurement that since the entangled state of the two spins has been affected by Alice's measurement, Bob's result is not a true result that he would have got if Alice had not made her measurement first. 2 Reply 2 replies Tavo Moneqz Tavo Moneqz 6 years ago i really fell in love with your videos, thank you, you made my modern physics student life easier. 2 Reply The ReaL LisT The ReaL LisT 9 years ago I have a huge grin on my face because I understood! Thank you :) 2 Reply Sheriour Sheriour 9 years ago Excellent video! I would just like to make one thing clear for myself. The "same" result is in no way priveleged in comparison with "different"? What I mean is that the 0.25 probability applies regardless of whether we focus on getting the same or different results? Reply VirginiaL H VirginiaL H 5 years ago This helped me quite a lot, thank you DrPhysicsA. 6 Reply Nishanth Sasankan Nishanth Sasankan 1 year ago I had a question, what about the cases when alice and bob picks the same polarizers (1,1) (2,2) and (3,3)? isn't that a key part of testing hidden variable? Reply Michael Hutton Michael Hutton 4 years ago Again, thank you for the wonderful videos. I love your style of presentation. However, I do think maybe this video could be redone? There are a few mistakes which could add the the confusion with a very conceptually difficult subject.... (and I do think I have no real place to criticise!) 1 Reply 2222 Malayalam Electronics 2222 Malayalam Electronics 1 month ago Hellow Bob! 10 years ago.. and 10 years after... thank you for the simplified explanation ❤ Reply Rusty Sim Rusty Sim 4 months ago I think this is the best explanation for Bell's theorem Reply INNOVATION & INITIATIVE Diy INNOVATION & INITIATIVE Diy 4 years ago You are best teacher of both maths and Physics :) Reply Valariegoose Valariegoose 7 months ago Best explaination so far...for years and I am surebfor years to come!. Thankyou! 1 Reply Pen and Paper Science Pen and Paper Science 2 days ago Great video. One question: What does it practically mean when you say that "Bob can't measure spin in the horizontal direction when he's told what it would have been in the vertical direction". Will the measurement outcome be undetermined? Reply Free Rehab Free Rehab 5 years ago I've watched so many videos trying to explain this. None made sense and I got lost. This was clear and easy to follow. Reply Philip R. Baldwin Philip R. Baldwin 3 years ago I think this is very useful, but a little confusing, due to the "typos". Any chance, DrPhysicsA, that you could redo it? Again, very valuable 1 Reply huddy buddy huddy buddy 5 years ago u r the best sir.. how easily u r describing.. 1 Reply Liliane Dubois Liliane Dubois 2 months ago Excellent presentation. The other explanation is that the 2 electrons do not communicate with each other but are both canceled immediately by an outside reactive force. Reply pritam roy pritam roy 1 month ago dear DR physics, six year back i started to watch your videos, then i was doing my Bsc. now I'm doing my phd , and still watch your videos for better clarification whenever I need in any of my research topic. thanks Dr physics. you really cured my 'lack of control on physics ' diseases .🧖🧖🧖 Reply Lawshorizon Lawshorizon 3 years ago The original two photons that spit off don't have the "same" polarization angle but polarization angles of 90 degrees to each other. However, in reality, they're in quantum limbo before registration so their polarization angle isn't established until they have something to have an angle in relation to (e.g. the polarization filter). Reply sudip patra sudip patra 5 years ago Thanks DrPhysics...but is there any reason that why the result is always less than 1/3? if you please explain... 2 Reply nnd nnd 8 years ago Maybe I'm missing something. Hidden variables theorem should also imply that by definition of entanglement, possibilities for both particles are not independant - 2 and 3 should be mutually exclusive. S probability should be zero for combinations (2,3) and (3,2). What do experiments show? 9 Reply 2 replies Grow Pot Cheaply Grow Pot Cheaply 5 years ago I want to point out that no matter what random numbers you assign to each section in the Venn diagram, it will always hold true that A not B + B not C is greater than A not C. You simply labeled them as 1, 2, 3, 4, 5, 6, 7, but some viewers might not see that it is true even if you change those numbers to anything you want. Let's try to make A not C larger than A not B + B not C. Is it possible?> I want to first point out that A not B cannot include the big half of C you labeled 7, because we are dealing with sets, so A not B means it must include A. 7 doesn't include A. Or another way to see A not B is the only place on the diagram where B is not part, but A is part, is section 4. Anyway, so now we have 1 not 3, which is the same as 1 + 4, and B not C is 3 not 7, which is the same as 3 + 2. Using the diagram, we want these numbers to be small, but the problem is A not C is the same as 1 + 2. 1+4 + 3+2 greater or equal to 1 + 2. If we make 1 = 20, and 2 = 20, and everything else in the diagram equal 2. We get. 20+2 + 2+20 greater or equal to 20+20. It holds true. 44 is greater than 40. No matter what numbers we place in each section, A not B + B not C will always be greater or equal to A not C. I only wanted to clarify this in case someone was thinking that there is a possible number combination that would make A not C greater. There is not. You can visually see that A not B + B not C is almost two circles, and A not C is almost 1 circle, if you shade them in. Basically A not B + B not C includes A not C, plus two more numbers, thus must be greater. Reply Suroj Dey Suroj Dey 7 years ago sir, i like ur videos can u make one explaining how color force works and how exchange force mechanism work(including attraction by virtual photons) sorry if u have already made a video... Reply DrPhysicsA · 1 reply steve Zara steve Zara 9 years ago Thank you. This is the first time I have seen this explained clearly. Reply DrPhysicsA DrPhysicsA 9 years ago I think you have it right. What I was trying to say was that altho Bob can obviously make a measurement he wont get a conclusive result if he measures the x component of the spin after Alice has measured the y component of the spin of the entangled particle. Reply chandan mazumdar chandan mazumdar 1 month ago Amazing, so neatly and so argumentative ly you have explained.. A big hug from me.. Thank 🙏 you Reply Quahntasy - Animating Universe Quahntasy - Animating Universe 2 years ago Who else is here in 2020 and still finds the video the very best. 116 Reply 23 replies DarkerRifle DarkerRifle 6 years ago I am interested in learning more about this can someone link me more information perhaps a more in depth look ? Reply Doug Rosengard Doug Rosengard 10 years ago The inequality refers to the number of elements in the sets. In your example for instance A={4,2,1,3} has four elements, B={b,w,r} has three elements and C={on,off} has two elements. The set "A not B" is the set of elements that are in A but that aren't in B which in this case equals the set A since A and B have no elements in common. Letting "#S" be the number of elements of set S, then #(A not B) = #A =4, #(B not C) = #B = 3 and #(A not C) = #A = 4, which since 4+3 > 4 matches the inequality. Reply Saadi Jalal Saadi Jalal 3 years ago Thanks for you effort sir. I am missing one thing. Why do particles have to have same polarisation in pair production process...is this a postulate? 1 Reply Moh Teeti Moh Teeti 4 years ago (edited) Thanks for this clear explanation. I'm not a physicist but love it. My question is as follows. According to the experiment setting, It seems to me that ruling out the existence of any hidden variables is based on the entangled particles, i.e., quantum entanglement is taken for granted. What would happen if the quantum entanglement itself does not always happen? Could the entanglement phenomenon be also probabilistic? 1 Reply 1 reply DrPhysicsA DrPhysicsA 9 years ago Sorry about the confusion. I should have used letters instead of numbers. I dont use them as population values. I use the numbers as a shorthand for the number of a particular category within each of the numbered sections Reply MrWillvee MrWillvee 6 years ago at the end you said experiment shows that you get the same result in alice and bob's laboratories greater than 1/4 of the time. You meant equal to 1/4 of the time right? great video by the way! very informative. Reply mark robinson mark robinson 1 year ago I think you need to consider an experimental set-up. With a simple polarizing filter, how do you know that there was a photon if it wasn’t detected? One experimental set-up has half transmitting/reflecting mirrors with detectors for both transmitted and reflected photons to detect each photon in place of the simple filter/detector in the 2 sides of the experiment. If you have near simultaneous detection in both polarizations of 1 photon the result is discarded as it is assumed that here happened to be 2 photons. Also if only 1 side of the experiment (Alice or Bob) detects a photon then this is also discarded. Problem is, if you consider that a photon can be a polarized magnetic wave that triggers a step change in energy level of an electron you get the same results. I think but don’t know that this might be called the fair sampling loop hole. Reply alun101 alun101 1 year ago Great explanation. I now get it. Reply Adam Rosillo Adam Rosillo 5 years ago Good explanation. just one question. Which A-Level syllabus is this in? I'm learning about it in the final year of my undergrad. It seems very difficult for A-Level students. 1 Reply DrPhysicsA · 1 reply Riadh Al Rabeh Riadh Al Rabeh 7 years ago There is a video under 'real time imaging of quantum entanglement' on utube and pdf by the same name on google that everyone should see. Online change in the polarization of one of a pair of entangled photons and shows the corresponding determined, repeatable and timely changes on the second of the pair. This does not need the Bell's inequality to accept and denies clearly the 'pair of gloves' or hidden variables argument. The easiest explanation to this is that action and reaction and the conservation of momentum are instantaneous and not affected by distance. There are two solutions to Maxwell equations. A dynamic one where photons travel across space at c, and a static one responsible for the static electric force (and the same for gravitational force), which is instantaneous and does not respect distance. QM being a good representative of nature must show these two effects- using a different route. Note that it is also 'probably' correct that no information can be carried by this method as energy travels only at c. 4 Reply 1 reply Chris Abela Chris Abela 1 year ago I can count twelve 'S' from twenty four possible {S, D}, therefore the probability of obtaining an 'S', if all the combinations (1 to 8) occur with the same frequency, should be exactly 1/2. I suppose that as we cannot establish the probability of the individual combinations, we have take 1/3 as the lower limit. Thanks for the clear presentation. 1 Reply Wouter Serryn Wouter Serryn 7 years ago Maybe space is bendable, and are these bends all around, but not perceivable by us. So there could be a 4dimensional bend/tube/wormhole, which keeps both positron and electron at exactly the same place, where they entangled in 4dimensional space, but doesn't in 3dimensional space. So the 2 entangled particles are still one object/form/energy. 8 Reply 3 replies Michael Lean Michael Lean 3 years ago This intro has been THE BEST explanation of the EPR paradox I've watched!! (and I've watched quite a few!!) Thankyou 6 Reply 1 reply Michael Harris Michael Harris 3 years ago (edited) This is very good. I'm just wondering did you need to put numbers on the areas, could you not have left it just with the letters. The numbers threw me because numbers are an amount but in this case they just represented different areas and had nothing to do with amount. But I've only just got some grasp on this. Tell me, did they need numbers? I know it's 7 years later so will not be surprised if not answered. Maybe someone else? Nearly forgot, thanks for making this video for all the amateur people like me who want to know everything. Reply Z. Pai Z. Pai 7 years ago Thank you, sir! Reply dlaxmcm1414 dlaxmcm1414 5 years ago (edited) I think the problem is in describing the spin of an entangled particle at 2 different locations. The experiment is set up to determine discrete characteristics (spin direction ><, /\ \/) of 2 distinct particles (e-, e+) at any given moment, as they pass through the polarizers. The idea that they are "communicating" is sort of a bad term, because those polarizers are moments of a collapsing wave function. If they have a momentum, and we try to describe discrete characteristics, then we must render their location irrelevant. Which is to say that they cease to exist in a wave, and collapse into both e- and e+, displaying spins that correlate. The 2 particles are only identifiable in 2 different locations, if we remove their momentum. That works in a thought experiment, or a video even, but not in real life. We can see the "shadow" of the spins they have as they interact with the polarizers, but the measurement of spin only matters in a 3 dimensional "slice" of 4 dimensional spacetime. Spin is only relevant to spacial dimensions as a direction of potential angular momentum. But there is no momentum, because we are observing the particle, in a definite location. So if we measure spin, we disregard time. If we say that 2 particles are entangled then we also have to disregard location or the distance between them. Spin is kind of like the shape of the wave in a 3d slice of space time. We imagine it as a "direction", but that direction lacks momentum. The wave function allows for what we would describe as "entanglement" because the wave doesn't give a shit about where the polarizers are. The wave, e-~e+ will always display the same characteristics at all locations. Instead of saying the 2 particles "communicate" faster than the speed of light, they are ALWAYS manifesting complimentary characteristics, because they are always part of the same wave. The particles are entangled because the wave doesn't care about location, and the particles don't care about time. 18 Reply Westsider95 Westsider95 6 years ago Seems to me the trials are not testing spin direction [which is the 50/50 proposition,] but instead identical polarization [which apparently should always be the same]? Also, in many cases [when Alice and Bob pick different polarizers,] the trial is not measuring spin in the same plane, which I thought was a condition for the spins of entangled particles to always be found to be opposite? 1 Reply swami aman swami aman 2 years ago Great explanation Sir ..... 1 Reply VesaVersion2 VesaVersion2 2 months ago I always thought it was about how different bells produced different levels of sound, therefore the name "Bells' inequailty". Reply alan jenkins alan jenkins 1 year ago For the curious the 0.25 probability comes from the equation Cos(120)*0.5+0.5. Substitute any rotation angle you want. 1 Reply 1 reply Larry Makow Larry Makow 1 month ago Great video as all of yours are. I think rather than saying that Bell's Theorem shows that quantum measurements cannot be explained by hidden variables, it would be slightly more accurate to say that Bell shows that quantum results cannot be reproduced if you impose (as EPR proposed) a requirement of locality. Bell acknowledges that Bohm managed to construct a hidden variable theory but points out that it is "grossly nonlocal." Reply aravind sr aravind sr 3 years ago I have watched many videos on this topic and I could not understand any of them... This one hits the right breadth and depth... 1 Reply Hasan Shirazi Hasan Shirazi 3 years ago How can you detect each and every entangled photon? There must be some detection errors which can explain this non locality issue. Reply Alper Duru Alper Duru 5 years ago Thank you for the video. What is the importance of the angles of the polarizers, if any? 1 Reply 1 reply Henry Minsky Henry Minsky 8 years ago There's some thing funny about the idea that the two experimenter's Alice and Bob are really randomly choosing the orientation of their polarizers. It's not like they stepped outside of the universe to do their experiment. They are in the universe, so the notion of 'random' is not clearly defined. Some people have suggested that the subatomic particles are made of some kind of smaller discrete deterministic cellular automata sort of rule, with purely local interactions. If the underlying mechanism of photons and other subatomic particles is deterministic, that would be a kind of 'hidden variables' or state that it is difficult for us to observe. And you would need to regard the experimenters, Alice and Bob, as being linked by some complex but deterministic series of steps of the cellular automata, i.e., you could follow their 'light cones' back to a common position in spacetime. So there doesn't have to be any 'spooky action at a distance', as they have been within communication range to each other at some point in the past. So no information has to go faster than light. But we can't look at the events (photons emitted, alice and bob moving their polarizers) as completely independent. Doesn't answer the question exactly, but shows there's more than just an isolated state in the photons independent of the experimenters. Reply Mohammad Bin Mahbub Mohammad Bin Mahbub 2 years ago But Professor, why did you not take into account the combinations where Alice and Bob chooses the same sets of polarizers. What would happen in that case? Reply 1 reply Chris Abela Chris Abela 1 year ago (edited) Does anyone knows of clear explanation on how quantum mechanics predicts the result of this experiment? Reply DrPhysicsA DrPhysicsA 9 years ago I don't think the experiment assumes that the hidden variables are random. But if they were not, then one would expect to find some consistency of results Reply onehit pick onehit pick 5 years ago (edited) I see the main error here is the assumption that there are two photons. There is just one single phenomena which propagates outward from the source like a pebble dropped in a pond, but only dual-beamed instead of circular wavefront. The measurement processes doesn't send information faster than light, but there are actually precursor ripples of the measurement which start way before the actual declared measurement begins. It's just classical wave mechanics and no mystery. It just requires ample noise. In the low noise approximation without precursors, it appears to be "mysterious". Also, please send me the specs on a polarizer that lets a photon "pass though or not". All polarizers I've encountered will absorb the photon via interaction with electrons and re-radiate a new one or not. 1 Reply Edem Sauce Edem Sauce 7 years ago I found that a version of the Monty Hall problem leads to similar conclusions. I made a video about it. I'd be happy to know your opinion. Thank you! Reply RamanSB RamanSB 9 years ago if the intensity of a photon was 1W/m^2 and you passed it through the arrangment of polarizers at 10:49 would the resultant intensity of the photon that makes it through both polarizers be: 0.5W/m^2 or 0.25W/m^2? Reply DrPhysicsA DrPhysicsA 9 years ago which is why the experiment is often described as measuring the spin of, say, an electron along the y axis. If one electron has spin up the other will be spin down. Reply Zephyr López Cervilla Zephyr López Cervilla 6 years ago How do Alice and Bob randomly select one of the three different polarisers each time? Couldn't it be that the embedded information (i.e., "hidden variables") were being shared with their randomness generators? 1 Reply 2 replies Altern 8 Altern 8 1 year ago (edited) I don't really get the first part about simultaneously measuring "spin in both X and z axes". Afaict electrons only have one spin direction, and if you try to measure it with magnets you have a certain chance of getting that spin or the exact opposite, depending on the previous spin. I.e. measuring with magnets reorientates the electron. In fact spin is just an emergent property of electrons in the presence of measurement apparatus 1 Reply DrPhysicsA DrPhysicsA 9 years ago Yes. That's why I say that at least 33% of the time you would expect it to be the same. 1 Reply azeer esmaeel azeer esmaeel 6 years ago but according to this reasoning, in order to preform this experiment correctly, one needs to cycle through all the options of measurements in orderly fashion (periodic, 9 in total for 2 detectors), and we do this over and over in order to be fair with each arrangement, after that we can decide if its spooky or not, but by choosing the detectors(polarization) randomly, then one might choose one arrangement much more than the other and that will miss up the probabilities. no? Reply teslammvii teslammvii 3 years ago at 20:20 the explanation should be that they are ENTANGLED. Otherwise indipendent photons with the same polarization will independently choose whether they pass or not from the filters and the result won't be the same every time. If for example the filter is at 45 degrees to said polarization then only half of the time the results will be the same. But if they have the same polarization through an entaglement process then it is 100% the same result. (disclamer: I am not a physicist) Reply Jim Hunt Jim Hunt 2 years ago Good explanation. Like it. Reply Yu Zhang Yu Zhang 6 years ago The 3rd case in your light polarizer example: photon goes through Vertical, 45 degree and then Horizontal polarizers. I think this is already a proof of sth weird. If I detect a photon after the 3 polarizers, one can not say the photon ORIGINALY has an polarization in horizontal direction (final one is horizontal), because, it would be blocked by the first vertical one at the beginning. So it seems the polarizer themselves changes the polarizaton of photons. So all experiments done by Alice and Bob are actually interacting with the spins or porizations. So no intrinsic, hidden variables. Can I say this? Reply 1 reply Krzysztof Chris Krzysztof Chris 6 years ago Finally I get it :)Than you for the video! Reply ANANT RED ANANT RED 9 years ago Shouldn't the probability of same outcome in your example be 1/2? I counted 12 S's out of the 24 experiments enlisted in the table. Sorry if I missed something elementary. Reply Matthew Lister Matthew Lister 5 years ago Hi. Thanks for the clear video. When you say Bob can't measure in the x-axis. What do you mean? What would occur if bob and Alice tried to measure x and y spin simultaneously? 2 Reply 1 reply Travelman Travelman 5 years ago very well explained!!! thaanks 1 Reply justhayden15 justhayden15 2 years ago Oddly understood this better than any animation Reply DrPhysicsA DrPhysicsA 9 years ago It is pairs of photons that are entangled rather than beams. But if photon A passes thro a 45deg polariser it would be possible for the entangled photon B to pass thro the horizontal polariser. There's a little more about this in my EPR Paradox video. Reply 1 reply jaxtraw jaxtraw 3 years ago What if the hidden variable is not the polarisation, but the probability? Doesn't that get round the problem? Reply Rathinakumar Visweswaran Rathinakumar Visweswaran 9 years ago Doesn't the experiment assume the "choosing of the hidden variable" to be random across the repetition of the experiment. Is it not possible that certain values like "1-pass 2-pass 3-dont" be of some preference due to the process of the experiment or so ..? Reply jonesgerard jonesgerard 9 years ago That doesn't sound complicated enough, it has no spookiness. But it sounds simple enough to be true. Reply Dale Griffiths Dale Griffiths 2 years ago Sorry DrP but why did you leave out SSS and SSS for row 1 and 8. In total there are 12 S out of possible 24 which is 1/2 so shouldnt you be comparing 0.25 to 0.5? Reply Medaphysics Repository Medaphysics Repository 5 years ago okay so can someone please explain to me how this implies that particles are entangled ? Reply Steinar Grinde Steinar Grinde 10 years ago I'm not sure what you're saying here, in the graph there are intersections between A, B and C. And you're right, the inequality he states there is not very advanced or complicated, it's simply a result of the "size" of category 3 and 4 being non-negative. Reply Leonhard Mayr Leonhard Mayr 6 years ago Out of 8 situations, you consider 6. Those 6 situations have a 1/3 chance of being the same outcome. If you multiply 6/8 * 1/3, this is 3/4*1/3, which = 1/4 or 0.25. Does this not mean anything? Is it really just a big coincidence that it equals 0.25? 1 Reply 1 reply DrPhysicsA DrPhysicsA 9 years ago The polarisers in my example should be 60 or 120 degrees apart. 13 Reply 1 reply CyrilleParis CyrilleParis 5 years ago I would had that French physicist Alain Aspect was, in 1982, the first to do the actual experiment proving that Bell inequality was violated (Aspect found the 0,25 in the end of the video). 10 Reply 2 replies Tulin Howey Tulin Howey 9 years ago nice. I love this stuff Reply 4π or 8π 4π or 8π 1 month ago Can Einstein's hidden-variables idea explain a Bell-type experiment with only two measurement directions? Let’s give Alice and Bob two choices – they can either measure their spin at 0 degrees or 180 degrees. According to Einstein’s hidden variables, the particles have already made up their mind about whether or not they will be measured as spin up or down for each of these filters. Let’s pretend that Alice’s particle decides to be spin up for 0°, spin down for 180°,(and the opposite for Bob). We can write this as UD for Alice, and DU for Bob. For different combinations of measurements, Alice and Bob will find: We can write this as UD for Alice, and DU for Bob. For different combinations of measurements, Alice and Bob will find: * Alice measures 0°, Bob measures 0°: different spins * Alice measures 0°, Bob measures 180°: same spin * Alice measures 180°, Bob measures 0°: same spin * Alice measures 180°, Bob measures 180°: different spins So 2/4 of the time, Alice and Bob make different measurements. So for half of the time, if Einstein is right, a spin measured by Alice and Bob a random direction should be different. This is the same as measured. Isn’t it strange that different measurement angles give different chances of having a different spin measured by Alice and Bob. 1) 2 measurement directions: 2/4 =50% of the time 2)3 measurement directions 5/9 = 55.5 % of the time 3)4 measurement directions 10/16 =62.5 %of the time Kind regards Reply ahacker ahacker 2 years ago Best video on this subject. Unfortunately it could have been a bit better if not for small hiccups. Reply Vap Vap 2 months ago this is so real and true Reply Richard Lewis Richard Lewis 4 years ago I really enjoyed the video which explained the issues very clearly. There was one point towards the end of the video where the two possibilities were discussed and one of those possibilities was that the two particles are in constant communication. There is a third possibility, namely that the two particles must be treated as a single system extended over the space separation and that it is at the point of measurement of one particle that the whole system is affected, thus changing the possible outcomes of the measurement of the other particle. This third possibility explains the results and does not violate the rule that wave transmission in spacetime is limited to the speed of light. It does mean that a measurement of an entangled system can result in instantaneous effects over a distance but this cannot be used to transmit useful information faster than light. Richard Reply 3 replies Aydin Tasdeler Aydin Tasdeler 3 years ago The electron pairs are connected using a "rope" or wave fabric - if I tug on the rope from one paired electron across the far side of the universe I instantly feel the tug on the other paired electron. It's all waves. Reply Ramy Magdy Ramy Magdy 5 years ago It's a great video but i want to ask two questions first why we try to explain the polarization by saying that light consists of photons ? because we explain interference of light by consider it as a wave not as a beam of light and second if we explain polarization by QM , by doing the measurement , the wave function is collapsed when you draw a vertical , then tilted then horizontal polarizers in the same order you explained it by saying that a photon may be a vertically or may be horizontally polarized until it enters the polarizer and then find out say it was vertically after passing through the first one how when it passes through the second polarizer the wave function arises again after it being collapsed ? or precisely , Is their a wave function that describe the photon that exist only when the photon is not observed , and hide when the photon is observed ? 1 Reply Eric Reiter Eric Reiter 6 years ago I was trying to find Suskind's video where he shows the result of Bell's ineq. Could not. Please can you send or show a link? Also, my understanding of Heisenberg's uncertainty principle is not about dimensions of x y and such, but rather is about position * momentum