Your Daily Equation #21: Bell's Theorem and the Non-locality of the Universe 

This video is just the best for someone like me, an amateur physics enthusiast, trying to understand the 2022 Nobel Prize. Thank you Professor Greene! I remember when I first saw The Elegant Universe on Nova in my bedroom as a kid in high school. You opened my mind to the beauty and wonder of the universe. It truly changed my life. I've also recently read The Hidden Reality. You are a treasure to humanity. I didn't expect to suddenly be gushing your praises, but you really have done so much for me when I think about it. So, thank you very much!

Professor, I just wanted to say how much I enjoy your presentations. I'm not a student or physicist, I'm just a retired automotive tech who has read all your books plus those of Lisa Randall, Leonard Susskind and Stephan Hawking and others. I can't do the math but it's a wonderful thing to listen, read and ponder the world around me. Especially these days. Thanks very much professor.

I've seen lots of attempts to explain this with fancy graphics but it never really clicked for me. Then this guy comes along and calmly explains it from his living room without any whizbang graphical aids and it all falls into place. Bravo, professor!

Wow thanks professor Greene, this is the first time ever that I have heard an explanation of this subject that I could get my head around. Have not missed one episode so far. Your Daily Equation is the best thing to have come out of this corona crisis for sure!

Professor Greene that was amazing! I have never seen or read a better explanation of Bell's Theorem than you have just given. Very clear, very passionate. It is a joy to share your joy of physics.

Dear Prof. Greene, Thank you again for this wonderful series. Like the previous “commenter”, I have not missed a single episode. And I also think that Your Daily Equation is one of the best things that have come about since the start of the Corona virus pandemic. I would also like to say that, although I am a Science graduate, unfortunately I have never been very good at Math(s). However, this last episode of Your Daily Equation (21), is the first time that I have ever managed to understand Bell’s Theorem. Thanks again! One small point that I would like mention, is that - during the Quantum Mechanics episode of the NOVA series : The Fabric of the Cosmos; you equated the EPR Entanglement proposal as being more like a pair of gloves, set in advance as left & right, rather than the standard QM picture of “Fuzziness” until measured. I thought that the pair of gloves analogy was an excellent way of putting it. I am only surprised that you did not mention it in yesterday’s episode. And I still maintain that The Fabric of the Cosmos episode on QM is one of the very best explanations & visualisations of aspects of Quantum Mechanics, from Probability Waves to the Entanglement pair of gloves. I am going to re-watch episode 21 of Your Daily Equation, to make sure that I can still understand Bell’s Theorem. Many thanks again Prof. Greene. with best regards, Paul C.

Being able to bridge the abyss between the formulas and the easy to relate to observable reality is truly a gift, which often, as it did in this case, brings understanding and happiness to the audience. Even to, as in this case, someone with a PhD in elementary particle physics. Thank you!

Dr. Greene's ability to explain complex phenomena in simple, understandable terms is so powerful it's akin to having your cognitive ability grow exponentially in the space of one hour. Watching his videos in various forums including this one is a treat to be cherished. How fascinating life has become with scholars like Brian Greene filling the internet with truly interesting, meaningful, and mind expanding information. Thank you, thank you, thank you.

Wonderful ! I love these none formal lessons where I understand everything

Finally understood Bell's inequality. Thank you.

Your video, your explanation is the best! I finally understood what's really going on with EPR and QM and Bell's Inequality. Thank you so much. You needed every minute of this video to explain it well, and you did explain it well.

Hi Dr. Greene. What a great explanation. Your ability to communicate complex physics in a way that's so graspable to us lay people never ceases to amaze me. In a future video, do you think you could give us a primer on what a "light cone" is? Thanks so much for these videos.

The best presentation/lecture I have ever seen. And great graphics.

Thank you, Brian. I am slowly working my way through these so that maybe I can understand them better. I very much appreciate your efforts.

Great intuitive, yet rigorous, description, of a complex physical phenomena, or in simpler terms, great teaching! Thanks for your time and effort in putting these explanations out in public.

Best video of the series. Your passion, enthusiasm, and intellect ooze in this one.

A wonderful, non technical explanation of one of the profound insights of quantum world. Have been a great admirer of your clarity of thought ever since I read The Elegant Universe and The Fabric of Cosmos. Thie admiration only grows after watching such videos. Keep sharing.

I am not sure whether you still read the comments, but I want to tell you that you are great!! I am a yoga teacher and I don't know much physics but I like to read and here and there read and saw videos about Bell's theorem but never understood what they are talking about. You made it so clear and simple, and showed how the ideas behind it are just mind blowing and wonderful. I loved it!!! And I want to thank you for taking time and explaining these beautiful things. I feel like adding, I cannot believe it, I cannot believe nonlocal causality, it is spooky :-). Thank you from Israel - I go through the daily equations one by one - really love it.

So far I ve watched so much of videos & read about Bell's theorem ,but description given by you sir is remarkable,now fully understood where the Einstein & Bohr world was conflicted .

BRAVO!!!!!!!!! To me, the layman that I am in your incredibly interesting field, you Professor Greene are an outstanding teacher enabling someone like me to understand in simple terms that which is complex and deeply non-intuitive. Thanks for doing this.

Professor Greene with all due respect, my head almost EXPLODED !!!

Your Daily Equation is the best thing to have come out of this corona crisis for sure.

Thanks Professor Greene. I have tried to grapple with the Bell's inequality theorem for a long time. Your video was the first one that I've seen that explained everything so clearly. I'm down with Covid right now but I feel lucky to have used this opportunity to come across your video.

Good series. Really enjoy them. When is the classes available?

This channel is the only one that I watch live, above working or parenting, because I simply can't wait a few hours and watch it later.

This is the best episode till now... Can you make an episode on quantum eraser problem too!! Please 🤩🤩

Thank you for making this subject clear it brings metaphysics to mind for me

gotta love this guy. i feel like i gained a lot of progress in my understanding of bells theorem although i still don't have the math figured out but that takes time. even still, it was a fascinating watch and i love his enthusiasm

Very appreciated, thank you. Clearest explanation I've seen yet.

Complete, simple, understandable, amazing explanation of the Bell’s article.

It's absolutely scandalous that Jon Bell didn't win a Noble prize for this 🤯🤯🤯

Thank you very much Dr. Green, I am absolutely delighted hearing you (indeed listening this more than one time)

Thank you, Dr. Green, for such wonderful series. We are all grateful for your hard work.

these are solid gold, love these videos so much

This was awesome. Thank you sm!

Dear Prof. please continue your daily equation for eternity , we are all definitely enjoying it.

Beautiful description of more complex ideas in simple words. Thanks professor

I love your stuff so much Brian.

Thanks, Dr. Green! Great video...beautiful explanation of this surprising aspect of science!

Amazing explanation. Thank you professor Greene.

Wonderfully and patiently explained

I was looking at nearly 10 videos to understand this concept and learnt 50% from those videos... With this one video I understood the whole concept and so amazing and gifted Brian greene... I dont mean I understand quantum mechanics which is always strange but the problem associated with EPR and Bell Please continue to make such videos as others only make talks but you talk in mathematical , descriptive and imagery explanations and it is mind bogglingly simple None could have thought that quantum mechanics could be so simply explainable

Need more series like this ❤️

Thank's for a clear explanation about this issue! Very many youtubers and other physicists try to explain it, but Brian Greene had it pretty well done. Thank You!

Thanks Brian, definitely the best explanation and animation I've seen of the test of Bell's inequality. But I think at the end of the video where you committed to a conclusion that the universe is non-local, missed an important concept that you seemed to allude to throughout your video, that being that the observers have free will and the experiments are random. Superdeterminism also still seems to be a clean solution to the entire problem, that being the randomness of the experiments and the free will of the experimenters might not exist. I would love to see a video with your thoughts on Superdeterminism. Thanks again for the great video :)

A very lucid description of Bell's Theorem. Many thanks.

Professor greene thank u for explaining such a wonderful topic. U made my day. Thank u sir.

Professor Greene is way better than I thought reading his books. Cool way to get things across!

Professor Greene, I really appreciate your video very much. It offers the best explanation for this phenomenon.

This goes straight through the head. Can't shake off what I've just learned.

That was a great lecture. Thank you. You’re an excellent teacher.

One of the best explanations of what I have never understood properly

Great video,thanks!

wonderfully explained Professor Greene! I had NDE a few years back, experiencing three flatlines in a twelve hour period, and since recovery, regularly experience the Pauli Effect, as well as much Jungian synchronicity…been a fan of Bell’s inequality ever since I read Fritjof Capra and the work of the Fundamental Fysiks Group, which has all helped me maintain a semblance of sanity since I awoke from the coma!

A very accessible explanation. Thank you.

Thanks 🙏 I was looking for this explanation.

Thanks for your talk. I loved the explanation. Thank you

professor you just nailed this. you are an awesome educator. looking forward to have something on quantum eraser experiment.

My head is ringing like a bell now (pun intended). I'm going to calm down now and ponder. Professor Greene, this is wonderful ! Thank You.

best explanation so far! finally i understood :D ...many thanks 👍👍👍

I think I finally(!), years and years too late, got it :). Thanks. A great presentation.

THANK YOU , Pro Green Great fun you cleared up the entanglement, I did not know that the particles were in flux between spinning up or spinning down .

What an amazing science communicator Prof Green is. Thank you for sharing your insights into this fascinating intellectual discussion that has been ongoing since the last millennium.

Thanks! You ere my best author!! Clear, as usual.

Trying for weeks to get my head around Bell's inequality. This one finally did it for me.

great explanation of this subject

So careful and step by step. Kudos 👏 💐 🥳 🎊

Thank you Brian greene. Great explanation

Wow! That’s so elegant! Definitely an inspiration!

Thank you, Brian.

Excellent! Thank you.

Thank YOU my friend

Great lecture, thanks!

Dear prof. Green your lecture is magnificent , it’s explains the most unintuitive result in such bright way we’re all just speechless. THANK YOU

Thanks, Brian; you’ve just given me an idea how to emulate/simulate a 3-axis spin of my axiomatic virtual particles in my “gedanken simulation” of 3D digital color space… 👍

I love you Prof. Greene for Spreading scientific knowledge in this Trumponian Dark Age. I'm a biology student and you showed me the wonderful world of physics!

Wow!! Best explanation of Bell‘s Theorem and non locality I‘ve heard ever!

Brilliant explanation!!!! Thank you!!

Just watched this thru for the second time, and it really explains the logic and 'dilemma' brilliantly. Where the EPR view could potentially be an over-simplification, I would suggest the underlying nature of entanglement to be as an oscillating dialogue between the pair of particles - as opposed to a single communication or signal prompted by measurement. Either way, of course, the Bell tests as conducted appear to strongly demonstrate against locality and the EPR proposals. Of course there still remain the potential loopholes as covered by you in detail Brian. Of these, I'd suggest the most compelling might be those based around the assumptions or premises of the Bell tests - not all of which may be as reliable or as airtight as our reasoning may appear to demonstrate. Fascinating topic!

Dr. Greene- Uhh WOW. Thank you 👍🏼👍🏼👍🏼👍🏼👍🏼

What a brilliant explanation! Thank you.

Excellent explanation!

🌹🌹🌹 Golden Like - Thanks For Sharing 💖💖💖

Great talk, thanks. I always assumed that Einstein agreed that the two particles were in superposition, but that they were just shown to be in opposite states when finally measured. It’s interesting that Einstein believed they had definite properties from creation.

I am fascinated with quantum physics and am loving your really well explained videos❤❤❤

Thank you. Great explanation!

Brian is so good at this. Great popularization.

I learned so much more about the EPR paradox from your description, than I did from studying the math. I say that grudgingly, but as a compliment. How did you get to the end without playing the super determinism card?

QM, hidden variables , EPR paradox I love them.

this explanation is a gift to all of us, it's as brilliant as Bell's theorem!

More mathematical one, but could you try to do something on the amazing theorem of quadratic reciprocity?

JUST EXCELLENT , THANKS

Totally brilliant presentation. I didn't expect to understand Bell (on any level) anytime soon. I was wrong!

Nice talk!

Well done.. Thank you.

Fantastic! Thanks!

One of the Exellent explaination of Bell's inequalities on RU-vid

I think you're great... every time I dont understand half of what you explain (but it his not on you, it is me) but I can never stop listening and watch the whole thing even if I got to come back to it later. I'll never be a physicist but I love hearing you Greene and Sean Carroll speak... I love the concepts that I understand only half way, but I dislike the math in it, so I take you guys' word for it that all you say has been mathematically and experimentally verified.

Thank you!

Sir could you give lectures related to space relation with time and clear concept of light waves.