> temp > à-trier > bell-s-theorem-the-quantum-venn-diagram-paradox-minutephysics

Bell's Theorem: The Quantum Venn Diagram Paradox

minutephysics - 2017-09-13

Featuring 3Blue1Brown
Watch the 2nd video on 3Blue1Brown here: https://www.youtube.com/watch?v=MzRCDLre1b4

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This video is about Bell's Theorem, one of the most fascinating results in 20th century physics. Even though Albert Einstein (together with collaborators in the EPR Paradox paper) wanted to show that quantum mechanics must be incomplete because it was nonlocal (he didn't like "spooky action at a distance"), John Bell managed to prove that any local real hidden variable theory would have to satisfy certain simple statistical properties that quantum mechanical experiments (and the theory that describes them) violate. Since then, GHZ and others have managed to extend the theoretical work, and Alain Aspect performed the first Bell test experiment in the late 1980s.

Thanks to Vince Rubinetti for the music: https://soundcloud.com/vincerubinetti/one-two-zeta

And thanks to Evan Miyazono, Aatish Bhatia, and Jasper Palfree for discussions and camaraderie during some of the inception of this video.

REFERENCES:

John Bell's Original Paper: http://inspirehep.net/record/31657/files/vol1p195-200_001.pdf

Quantum Theory and Reality: https://www.scientificamerican.com/media/pdf/197911_0158.pdf

"What Bell Did" By Tim Maudlin: https://arxiv.org/pdf/1408.1826

Bell's Theorem on Wikipedia: https://en.wikipedia.org/wiki/Bell%27s_theorem

2015 experimental confirmation that QM violates Bell's theorem: https://arxiv.org/pdf/1508.05949.pdf
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.115.250402

Bell's Theorem without Inequalities (GHZ): http://dx.doi.org/10.1119/1.16243

Kochen-Specker Theorem: https://en.wikipedia.org/wiki/Kochen–Specker_theorem

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Created by Henry Reich

Дима Авениччи - 2019-07-27

Universe: can we have math please?
Quantum physics: we have math at home
Math at home: 15+15=50

Bearded Dragon Man 1997 - 2020-02-15

El Zed cool....

Andrei Pleșa - 2020-02-15

what if the glass don t stop the light but it change it direction ,so if glass don stop the light means we dont see light because it mive on a direction where it cannot pass through the glass ,Idon t understant we cannot consider problem in this form where the angle only go little by little out ?

Jesse Dugal - 2020-03-02

I'll show u a system of numbers that doesn't circle back to zero after nine. It's elementary it should not be worshipped

Viper Gas - 2020-03-20

@Jesse Dugal joke?

Jesse Dugal - 2020-03-20

@Viper Gas ya sorry I'm just kidding

Greg Forgotmylastname - 2020-02-19

God: "It's just a bug."

God - 2020-03-10

Exactly

Joseph Shapkauski - 2020-03-10

@God why have you forsaken me, in your heart forsaken me, in your mind FORSAKEN MEEEE OH

Mister Victorlee - 2020-03-17

The next patch is coming...prepare for a nerf to server population.

Tom Whipp - 2020-03-19

It's not a bug, it's a feature!

Truman Burbank - 2019-10-22

The second time watching this video, I tilted my head 90 degrees -- and forgot everything.

Jason Kelly - 2020-01-30

photons are units, so if I made a really dim light, instead of the light getting dimmer and dimmer, eventually it will just hit in as single photons less and less often. Bell's inequality is sort of how it takes more gas to drive the same distance in less time. When you have three polarizers 22.5 degrees apart, more photons come through than two 45 degrees apart; the photons do not have to change their polarization as much in each step, so it would take less energy, but since photons are quantum, they get through less often instead of having less energy. It is analogous to carrying a pile of bricks, if I asked 100 students to carry 100 bricks 50 yards in a single trip, no one would be able to do it, but if I allow more trips, more people will be able to do it, if there is no limit to the trips everyone can do it.

舞動單車BikeDance - 2019-07-05

i just want to make a "dark" room using those double layers as a wall to make it "black", and then if a person wears another glasses with that lens, he will be able to see outside the room😂

really wanna try that🤣

Yahya Karimipanah - 2020-03-07

@juan marquez I think what you are talking about is "common sense" or "intuition", not logic. It is definitely counter-intuitive but not logical.

Boleslav Hnipirdo - 2020-03-11

It will not work. Try a better spell. Put on polarizing glasses (from 3D cinema - with circular polarization) and try to blink your eyes in front of the bathroom mirror. It will surely captivate you.

Char [GD] - 2020-03-17

but the filter should be between the 2 90 degree separated filters

MP GAMING - 2020-03-19

Good idea

Leo Hao - 2020-03-22

@舞動單車BikeDance
it's called a variable ND filter or variable polarizer filter mostly used in photography and cinematography but I suppose you can use it in glasses

Frank Medrisch - 2019-06-15

There is an 85% chance you will not understand this video if you watch it once, and a 100% chance if you watch it twice

Robert Rudd - 2020-02-11

Frank Medrisch It is called Non-Sense....Then the makers of the video move “on” N-Sense!

William Jeffreys - 2020-02-12

I'm definitely going to need another watch or two.

The Løser - 2020-02-19

So I understand 50% more🤔

Crystal S-R - 2020-02-24

You spelled 15 wrong.
- me a bitch who's always wrong

F0rscher - 2020-03-05

I will add to your observation that a third or fourth time doesn't help..

Baruch Hashem - 2020-01-24

IRS: Your accounts don't balance.
Company: Turn the Balance Sheet 45°

arfumis - 2019-07-23

maybe the angle of the wave changes going through the polarizing filter

HaloVivek13 - 2020-03-03

@Sergey tinldw Why would you think that? What they said seems entirely accurate and reasonable to me.

well, shit - 2020-03-06

@HaloVivek13 well a functioning robot could be a lot more accurate and reasonable than a human

Jacopo Tomalino - 2020-03-09

@ColumbineLegend 420 (almost) 100% of photons, whose waves would have though changed amplitude and therefore energy, being as a consequence less visible. That would lead to a decrease in "light" as we think about it. If you think about what would happen to a single photon going through the filter and you calculate the final amplitude based on that hypothesis, it happens to match with the experiment.
I'm not an expert but I think the flaw here consists in the fact that he assumes photons cannot just lose energy or pass partially through the filter.
I mean, photons are quantized so you cannot reduce their energy for an infinite number of times, because sometimes you're going to reach the lower possible energy, but until you reach that point I don't see the problem with it.
With just a few filters and high energy photons such as the ones used in the demonstration, the number of photons getting to such a state is insignificant among the observable result.
In my opinion, this experiment should be repeated with very low energy photons to see if they would appear to behave similarly or not.
If I said anything wrong please tell me because I repeat that I'm not an expert and I really want to understand this phenomenon properly.

Quitschi - 2020-03-17

Yeah, sure, but that's not the weird part. The weird part is when it's 85% instead of 75%.

Leo Hao - 2020-03-22

maybe the light angle is constantly rotating at a not constant speed and acceleration and jerk and jerk acceleration, and jerk jerk......

VampireJester - 2019-07-20

I love how youtube recommends this to me almost 2 years later.

Asher schmidt - 2019-07-27

It's a trend... I get a few videos seven years recommended.

Atticus Moore - 2020-01-04

Three years now

Me And mine - 2020-02-05

Man: you can't confuse me
Universe: hold my really big beer

Hafiz Azim - 2019-10-21

"that would be crazy" - continues to explain.

George Francis - 2019-09-23

So remember how in the matrix, the guy said that certain things have to be imperfect otherwise we’d know we’re in a simulation

Kyra - 2019-11-08

👌

PokeMageTech - 2020-02-20

Yeah... not physics. I’m now thinking we’re simulated, and the details of objects only exist when we need them to. Have a chair? It’s empty until you go to cut it open.

Electric Sheep - 2020-03-07

@PokeMageTech Why would you cut open a chair?

PokeMageTech - 2020-03-07

Electric Sheep
Because you’re repurposing the material, or you’re destroying it, or you didn’t actually cut it but did break it.

Wes - 2020-03-09

We just live in a simulated universe that's the pornhub for greater deities. xD

Taco-Tanner - 2019-07-06

So it's quantum physics. It is one thing until you measure it and then it is another because you measured it.

Libertarian Leninist Rants - 2019-07-06

isn't it two things at once until you measure it?

Taco-Tanner - 2019-07-06

@Libertarian Leninist Rants yes. I meant one as in a. Not singular. Sorry I wasn't clearer.

Leo Hao - 2020-03-22

Shouldn't it be it's two things at once until you measure it when you discover that it was this but now it's that because you measured it?

Stale Bagelz - 2017-11-25

So when is this bug gonna be patched?

Sanjay Gupta - 2019-11-17

Man , that's funny

AtotheKres - 2019-11-17

@TheMiningTeam so you mean vendor support has expired?

Squidian The Bo Fish - 2020-02-15

So if I have a pitch dark room, and I put 4 bright light bulbs in the four corners of the room, and I encase those lightbulbs inside double layered polarized lenses to make the room pitch dark again, I can then walk around the pitch dark room with a printer paper sized polarized transparent film in my hands and see the pitch dark room fully lit through it?

Bravo Tango - 2020-02-17

We are going to need a bigger boat ..... 😊

Nicolas VERHELST - 2020-02-25

Hahaha 😂😂😂

Kati West - 2020-03-20

"Universe does not obey local realism" is the takeaway, guys!!

wes johnson - 2020-01-13

Amazing 9 out of 10 here think this is about light going through filters. Doesn't the reference to Bell's Theorem in the title make them wonder?

Klaa2 - 2020-03-08

The nature of light though is not intuitive at all.

Luny Cipres - 2019-09-29

Guys I thought minute physics is like "minute" as in small

NoriMori - 2019-07-19

<insert "most ambitious crossover" joke here>

Oat lord - 2017-10-27

I'm sadly not smart enough to even be confused by this.

Ingerecht annon - 2019-12-27

@Lisa there can be a hidden variable if you refuse to see it then if there is variable it would remain hidden even if you can evaluate the results I have an entanglement with this video supos you invent a variable that you can not see does the variablele exist just because you made it? if you made it up it exists is it hidden or are we just not mathematically complex enough x times the square root of negative one kind of complex. I am still hidden

Ingerecht annon - 2019-12-27

@Sean Regehr seems like there could be more to your comment cause at the bottom it says read more but it will not extend is this like a flat quantum versus globe classic physics conflict of information? Send some links to tmovoice "at"gmail "dot"com if youtube comment machine sees HTML links in my comment it kills them thanks in advance for any replies this video is a brain twister thanks again!

Tina H - 2020-02-28

Oat lord Funniest comment I’ve read in ages! 👏🏼👏🏼👏🏼

Jake Zee - 2020-03-08

Matt Kilgore for a short moment they show that the amount of polarized light that passes through a polarizer while already unidirectionally polarized (omnidirectional is most light, polarized in all 360 degrees at once; unidirectional polarization is a specific angle of polarization) is cos^2(of the difference in angles of polarization). If you do the math with 3 polarizers at different angles it will work out. This is a basic principle in photonics. As a photonics student, I’m not sure where the quantum physics come in; to me it’s basic photonics that is not properly explained (unless I’m missing the point because they aren’t giving any explanations).

OP-Gamer - 2020-03-22

Even me

Dat Tilson - 2019-07-05

Hasn't any considered that passing through the filter changes the spin/orientation in some way of the photons, and so the ones that do pass are now realigned with that filter?

WarimUrlaub666 - 2020-02-07

@Rogério Costa photons are not exclusive to visible light. Microwaves do also have photons.
Our visible light is really not that special. It just happened that our cells in the retina have proteins matching this wavelength in size. And therefore creates a detectable interaction - > vision

Evonix - 2020-02-08

That seems to be what he's saying

Dean Su - 2020-02-29

He mentions that very possibility at 8:55, then goes on to show why it doesn't work if you assume no faster than light communication. In the entanglement example the photons seem to be pass through their own separate filters as if the change in orientation of one photon somehow affects the other photon. But they were literally too far apart for hidden signals to travel at the speed of light, so if there was some sort of influence it is FTL

Alexandru Oprica - 2020-03-08

@Dean Su I know how the Bell experiments work and understand them but the language they use in this video very clearly leads to a possibility that they sorta brush over. They call the philters 'polarizING' which just based on this video alone makes me think 'oh yeah. Filter A changes the photons so of course you can't talk about a photon having a hidden variable that lets it pass through A and not C, since after the first pass, it's variables are changed'.
Not saying Bell's theorem is wrong, just that this explanation sounds botched.

Aries Dane - 2020-03-11

Yes, that does make a lot more sense. But don't count on a quantum physicist agreeing with you. Their entire science is built around absurd theories involving light traveling through slits in a box with a half dead cat. It's a joke.

Benjamin Cushwa - 2019-08-12

As a physicist and a photographer, this video was supremely satisfying and interesting.


Thank you both Henry and Grant.

Gumbo Clay - 2019-10-07

"Siamese lenses, connected via the polarizing system, with ingestion by A, passing through B, and excretion by C. The Quantum Centipede, first sequence."

Ritwik Chakraborty - 2019-11-24

I love minute physics, I have beard, and I wear glasses...so I am uncommon of all...😂😂

Gregory Dixon - 2017-09-14

Longest minute of my life

JavaFloof - 2019-06-21

Ponk 80 lmao its a joke

Andrew Heckman - 2019-06-27

Freely Liberal how could he tell which meaning was right. Its not like many people still use the word minute in the context of small. It was more likely to be minute as in 60 seconds. And what does all of this have to do with school

Reuged - 2019-07-17

Time is relative man !!!!

Sahil khan - 2019-12-23

@Ponk 80 he said minute btw😂

PFunk _ - 2020-01-14

Who cares

Matthew Pearson - 2019-07-09

6:17 in the Venn diagram how do some get blocked by b and still make it to c

con ty - 2019-11-29

Exactly

Rain Storm - 2020-03-09

I think it is "would it pass through C" not "passes through 3"

Koalaheikki - 2019-06-27

Sooo... Reality is unrealistic?

ehud kotegaro - 2019-10-27

Yea

Eduardo Wada - 2019-12-11

or it's not local

nck1Dlarrie - 2020-03-15

i love how i didn’t understand any of it

love a little bit of feeling dumb at the end of the day ngl

Yuvanesh Silvanathan - 2019-12-08

That background music makes me take myself even less seriously.

Fizizy - 2017-09-16

Today I learned I am not smart.

Zadron Xion - 2019-04-23

LOL! No one is technically smart because there is always something everyone doesn't understand.

Gibe Mass - 2019-05-11

Today I learned I'm smarter than all of you, I slowed playback speed.

A MAC - 2019-05-30

LOLing!

Same.

Luke Martin - 2020-02-20

It is more to do with accumulated knowledge rather than how smart you are.

PokeMageTech - 2020-02-20

Fizizy
Most people aren’t.

dave john - 2020-03-18

That's as mad as asking: "Do a thousand lava lamps synchronize?"

Stilick Oh - 2019-06-26

minute physics?

more like

more than a few minutes physics

Serendiphia Aesthent - 2020-03-15

yes, i watched the whole thing
and yes, i dont understand a thing

Crystal Hexagon - 2020-03-09

When math and physics come together KA BOOM !!!!

Rain Storm - 2020-03-09

I was about to ask; "What if the filter affects the photons when they go through?" Then they asked just that

game movie - 2019-09-08

It will be fixed in next update.
Large anti-cheat update coming......

Advanced Learning Algorithm - 2019-07-08

Thank you for making this video! Seeing all the questions and discussion in the comments is amazing.

jeffmurnahan - 2019-07-03

A minute of physics in dragon ball z time

realitynowassigned - 2020-03-18

I wamt sunglasses made with these as the max polarization. Several. So I'll always looking only at the light i know i observed

Matthew Egan - 2019-07-13

Umm maybe the photons are not consistently aligned in up or down / left or right.

When it goes through a filter maybe it shifted the alignment. And when it goes through the next filter it shifted it's alignment again.

FLAVIO da Brescia - 2019-07-17

You sir are an engineer, and understand things. Those guys like to NOT understand them.

DesertCow1000 - 2019-07-17

This is sort of what I was thinking ... the polarization changes the state of the photon waveform, altering it's reception by the next filter?
Or maybe I'm just overthinking it
🤔🤨

brandon stroup - 2019-07-17

i have a low IQ, but i agree with this as i thought of it also while they were talking about the photons not being consistent when you introduce b in between a and c. there has to be some kind of alignment shift at b.

Francesco Sarandrea - 2019-07-19

What you suggest is very reasonable, and indeed is considered in the video from minute 8:46 onwards (it's what they call the "dynamical variables" scenario).

Michael Podolsky - 2019-07-21

Of course photons are changing their polarization when passing a polarizong filter. Authors for some reason prefered to ignore this fact in the course of their analysis.

jrdonat - 2019-10-29

“Minute”

Chris P - 2019-10-14

It's called collapsing the wave function via observation.

NeilIsBored2 - 2019-03-16

Have incredibly tiny gnomes been ruled out?

Dr. strange - 2019-07-12

@Yargle Glutton of Urborg here!🙋

Rosie Puplett - 2019-07-15

If I could upvote you a million times for the username/video/comment combo I would. I salute you :D

Michael Sommers - 2019-08-26

@Yargle Glutton of Urborg They aren't yours, they're free.

Bruce Martin - 2019-09-10

I saw one sitting on my window sill. Just watching me sleep. He looked jealous but idk if gnome body language translates

Dean Su - 2020-02-29

They'd have to be faster than light gnomes

Haris Y - 2020-02-20

I love how they failed show it being brighter by placing a text pointing to supposed brighter spot :/

Ken Collins - 2020-03-06

This is exactly what I thought!

I knew it!

tuluks Vui - 2019-07-03

I think I'm part of the 15% who didn't pass through filter A who didn't understand this vid

jismerai verhoeven - 2019-07-08

actually i think they removed the second filter and made 50% of the people get blocked from understanding ;-)

Der Archon - 2020-03-07

Just imagine you have a bottle of water an pour it through a filter and only 50% of teh water passes through. So you have now only 50% of your water after the filter. You install a second filter and the remaining 50% are blocked and you have no water anymore. You install a third filter and suddenly water pours out of the filter. This actually happens with light in this video and now you do maybe know why this is fucked up.

Schema:

|||||| <- Water

_ <- Filter
| | |
_

_
| |

oussa - 2020-02-25

my friend you have a very beautifull voice :D

Continual Improvement - 2017-09-13

I don't normally make diagram jokes but Venn I do...

Ray Hewitt - 2017-09-16

I gave you "Like" number 1,000. I want my "no-prize".

Philip Osborne - 2018-04-04

This is how AI will decide when to laugh or not...

GetMeThere1 - 2018-08-18

Wouldn't it be "yokes," then?

J C - 2018-10-31

Oh no you didint

Fifth House - 2019-03-05

How dad do you joke? I bet you never dad'd THIS hard

Shane Powers - 2019-12-27

Maybe a photon passing through a filter gets spun, and is oriented differently when it gets to another filter.

Rakhu Ramai - 2019-11-18

Fascinating! Though I got lost from the proof part 😁

Gishal :D - 2019-07-04

Physics: Well shall explain reality!
Quantum Physics: maybe. probably not.

Andy Blizzard - 2019-07-06

Maybe yes, or maybe not. I don't care, I am hot!