Quantum Entanglement & Spooky Action at a Distance
ฝัง
- เผยแพร่เมื่อ 31 พ.ค. 2024
- Does quantum entanglement make faster-than-light communication possible?
What is NOT random? bit.ly/NOTrandoVe
First, I know this video is not easy to understand. Thank you for taking the time to attempt to understand it. I've been working on this for over six months over which time my understanding has improved. Quantum entanglement and spooky action at a distance are still debated by professors of quantum physics (I know because I discussed this topic with two of them).
Does hidden information (called hidden variables by physicists) exist? If it does, the experiment violating Bell inequalities indicates that hidden variables must update faster than light - they would be considered 'non-local'. On the other hand if you don't consider the spins before you make the measurement then you could simply say hidden variables don't exist and whenever you measure spins in the same direction you always get opposite results, which makes sense since angular momentum must be conserved in the universe.
Everyone agrees that quantum entanglement does not allow information to be transmitted faster that light. There is no action either detector operator could take to signal the other one - regardless of the choice of measurement direction, the measured spins are random with 50/50 probability of up/down.
Special thanks to:
Prof. Stephen Bartlett, University of Sydney: bit.ly/1xSosoJ
Prof. John Preskill, Caltech: bit.ly/1y8mJut
Looking Glass Universe: bit.ly/17zZH7l
Physics Girl: bit.ly/PhysGirl
MinutePhysics: bit.ly/MinPhys
Community Channel: bit.ly/CommChannel
Nigel, Helen, Luke, and Simon for comments on earlier drafts of this video.
Filmed in part by Scott Lewis: google.com/+scottlewis
Music by Amarante "One Last Time": bit.ly/VeAmarante
"To understand spin, imagine a ball which is spinning, except it's not spinning and it's not a ball."
It is a property of a particle. We do not observe it in our macro world, so we do not have a word for it. So they called it a spin because it was the most appropriate word they could think of. It is hard to explain something you cannot observe by your senses, only the experiments give you information about it.
It’s easier than you may think. Mathematically if particles would have initially coordinate their spins it would give different result as opposed to what happens in reality. Meaning, if you throw a tennis ball on the wall on 60 degrees and the pair of that ball must behave exactly opposite then it should be 60/90 times or 2/3 of the time. If they calculate several possibilities of it like if 75 degrees 75/90 vs 25/90 etc then they compare it with what really happens it gives different result. If expected opposite percentage of spin is not equal to actual percentage measured in different angles of measurement then particles don’t have predetermined coordination. The only argument against thus may be that our math is incorrect, meaning math or probability as we perceive is completely irrelevant in this case. And I think Einstein could argue his case too. If there’s no specific “one” in this case then how can we say what would we expect from particles in the first place if they talked with each other before measuring. One particle can be on different places at the same time. There’s no one and zero in quantum physics, there’s no math here so talking about probability makes no sense.
holy crap !
@@johnphantom Can you make some kind of video or picture explanation of that thing. I am quite intrigued but I don't think I understand it properly. A video or picture will definitely help! Thank you!
@@abdullamasud4278 I think the best way to visualise it would be to model the simple calculator in Minecraft. Unfortunately, I know nothing about that application. I am looking for someone to help me.
i am in a superposition of understanding this video and not understanding it at the same time...
I got collapsed at not understanding it 100% of the time
nvm i get it now
Hahaha
Angular momentum is always conserved in the universe. Fundamental particles have angular momentum. As far as we can tell Quantum mechanics is inherently probabilistic so when you measure the angular momentum of a fundamental particle the result is random. When these two meet it seems that for angular momentum to always be conserved in the universe when the angular momentum of a particle is found another particle must change to be opposite of what it is, other wise angular momentum would change ever so slightly, and this is what we do observe with particles that are Quantum entangled i.e. the pair that change to always be opposites
I just checked and your wave function of all possible states collapsed into a single state: you don't understand it.
I remember watching this video when it was released as a first year uni student. Now I work with quantum entanglement on a daily basis and this video was one of the things that piqued my interest in this field
Quantum physics is the truth of universe and lie of human consciousness saying that it does not need any observer or audience it knows its nature and truth
Specially in quantum entanglement universe is constant it knows what is up or down so where ever the particles go their nature is pre determined its just us making it complicated by knowing it after so many years of evolution
That's awesome
Aye, good for you man. I remembered when I first saw this video I thought to myself how crazy it is that we were even able to test hidden variables vs. quantum stuff. It was so abstract, and yet the experiment basically settles it. Kind of awesome
@@GoodVibes-pj9wd ehm.... What?
I just sat down, listen intently to the contents of this video, and suddenly 9 minutes have passed without me knowing it and the video ends. What a brilliant presentation.
The particles may not be actually spinning but my head certainly is.
Lol
Oooh Boy... It surely did....
If you said otherwise you'd probably be misunderstanding something :p
Another applicable principal to spooky would be "vibes". Ever "vibed" with someone or say the same thing at the same time? That's one other application to spooky.
So what's the use of "spin"?
He lost me when he said "They're not actually spinning of course, they just have angular momentum and direction".
Yeah. I needed further explanation on that one.
Still do.
@Smit Shilpatul
Point objects ? I thought electron radius is on the order of 10^-17 m and also there are no actual material points in physics ?
@@Hexanitrobenzene there are no points kn physics, but there are en quantum mechanics, they're called quarks
I think the difference can be described as the orbit of the earth around the sun and it’s daily revolution. Both are a type of spin; I think he means to say the spin of the particles is more like that of earth’s annual revolution
@Smit Shilpatul so they are like packets of angular momentum?
I remember watching this video when it came out back when I had just finished primary school, I barely understood anything. Now rewatching it, as I'm in the midst of my Quantum Mechanics course in Uni, it's both nostalgic and satisfying finally being able to make sense of these concepts. Amazing video, thank you!
Awww~ I really really really admire QM students 🥰🤩 You're epic~
In 6 yrs you jumped from primary school to university like how?
@@PDBisht in Europe when we say primary school we often mean primary and middle school so from "i just finished primary school" I think he meant something like just beggining High School
And in my country high School is 3/4 Years so it is possible to get into University after 4/5 Years of finishing "primary school"
@@PDBisht at least thats what I've been taught and seen being used
@@itiso1123 ah! I see here primary usually means 1-5 years of school after doing your pre-school and then 5 years of middle school after that 2 years of high school then only you'll able to enroll in college/university..
It's very complicated but I find this fascinating. It's one of those educational video's that you need to watch a couple of times before you start to understand.
Im not understanding :(
for real, how a particle can "give spin up for every measurement direction" by definition.. it's doesn't make sense..
and then try to explain this to someone but fail
Heisenberg and Schrödinger get pulled over for speeding.
The cop asks Heisenberg "Do you know how fast you were going?"
Heisenberg replies, "No, but we know exactly where we are!"
The officer looks at him confused and says "you were going 108 miles per hour!"
Heisenberg throws his arms up and cries, "Great! Now we're lost!"
The officer looks over the car and asks Schrödinger if the two men have anything in the trunk.
"A cat," Schrödinger replies.
The cop opens the trunk and yells "Hey! This cat is dead."
Schrödinger angrily replies, "Well he is now."
HAhahaahha
Very clever QM joke.
@Brett Dawson Cop shoots the cat, Schrodinger sues the City for unlawful death and wins case. Cop becomes lunatic
@fly med I never heard it before! So I'm okay with it. Hey, how about people who were born after the 1960s? They shouldn't hear it because you already have?
And of course, the cop THEN says, "Well, you do have a SPARE cat in your trunk, don't you?"
I understood everything up to 00:01
👌
Lol
lmao
But I Also Understood from last 0:01 sec
Wow, Veritacium teaches so well you understood it by 00:01.
I've always struggled to understand the experiments you mentioned regarding measuring entangled particles, and I found your visual representations to be very helpful.
I like the idea of living in a "probabilistic" universe that just gets concrete when things are measured. So, this entangled particles don't need to exchange any information. It's just the observer who, by measuring the spin of one of them, enters into a specific universe in which the other particle is (and always has been) consistent with the measured one.
Superposition baby
the "spin" is a mathematical ASSUMPTION not based on observation .
this is NOT science , it is invention to fill the gaps in our understanding .
@@sambennett996 I googled what you said for clarification and kept finding results of "babies" and "gender" and "quantum physics"...then I realized "baby" wasn't part of the term. 🤭
@@sambennett996 pls check my comment on this video. thanks
This view isn't as feasible as living in an idealistic world, it's an odd suggestion in favor of materialism that in order to be possible there has to be multiple earths with every single different probability and combination existing on it. But there are billions of billions of humans, with trillions and trillions of cells, all of which go through this same process. Meaning their are billions times billions times billions times trillions of other earths, which is a much more convoluted answer than something that can simply just be explained by idealism which is that reality is a mental construct and doesn't exist independent of observation.
I've watched this explained 50 times, 50 different ways, and I still only understand 50% of it.
And for some reason, it's still interesting.
Still sounds like a telemarketing video trying to sell you some useless product.
You understand it and not understand it at the same time
@@OvoJeGovno shrodinger's understanding
I have been trying to get a grasp on quantum entanglement for a while now, I still don't think I understand any of it.
@@OvoJeGovno thats cos there was one universe in which you understand it and another one where you dont :) you are just superimposed now ;-)
In order to understand that we don't understand entanglement, we should first understand that we don't understand spin.
In order to understand, we must disunderstand.
@@stupidrainbo is this xavier angel renegade?
@@stupidrainbo But somehow, our disunderstandment must be entangled with a "clearly understood" state. Preferably a "charmed bottom" state. Heh.
@@Trollificusv2 Charmed bottom... heh
Understanding how much you don't understand is the first step in understanding.
This video is straight fuego 🔥. Veritasium always explains things so clearly and carefully. I'm so grateful for all these dope science educators on yt so I can keep learning even after graduating. Cheers!
Thank You so much for the short but very clear explanation at the end about why faster than light communication is impossible using entanglement. I finally understand something I have been trying to understand for years.
the spooky thing is, you're using yourself as a particle
Fifi Phoebe That looks very weird
xD
Lol!! Good one
It's time to *s p o o k e*
I really wish there was a good video explanation of what a particle spin is....ive never understood it.
and no one really does... That's the problem. Particles have angular momentum and direction but they're not really spinning like a classical object.
Veritasium I don't suppose you could make a video explaining spin some time in the future - if its possible to explain it.
Mee It is a property of atomic objects which has no (known) equivalent at our "scale". I think calling it "spin" is also confusing because people immediately relate it to our idea of what spin means when it's something different.
TheShreester what do you mean by no known scale? If we can measure this property of "spin" surely its something that can be described in terms of what it is ..
I said "no known equivalent at our (macro) scale" because there isn't one. The idea that particles have spin is an analogy intended to help us visualise what is going on.
Watching this video after the Nobel for Physics got announced. Gives me a basic idea of Quantum entanglement.
INCREDIBLE VIDEO!!!!!!! I knew this was not going to be easy to understand. So I cleared my mind, sat back relaxed, and gave all my brain to understand this and also watched it 3 times, and I am really happy to totally understand what all you said. For me, It was my first video about the Quantum entanglement and you did a perfect job in keeping me enthusiastic about this SPOOKY topic ;D
I totally agree with you man, I’ve watched it years ago and didn’t understand well but I came back more intelligent and now I totally was able to understand him, I had to pause and rewind so many times 😂
"In order to understand it we must first understand spin. All fundamental particles have a property called spin. No, they're not actually spinning." You lost me. (0:41)
I looked up angular momentum in Wikipedia, and it had an still image of a gyroscope, spinning.
I'm also a little confused about how they have an angular momentum without spinning... I thought you needed one to have the other
the problem is that the particle doesn't have a physical form, so it can't really spin, but it still have angular momentum.
They may not have spin, but they are charming.
Why not? The moon will have angular momentum because it revolves around the earth (even if it does not spin around its own axis)
"If you think you've understood quantum mechanics, then congratulations, you've not understood quantum mechanics"
- Richard Feynman
He doesn't give congratulation for not understanding something. Be precise when using quotes.
God, I love that guy.
hehe...is this statement real ?
@@ananyasrivastava5128 It goes like this. If you think you understand quantum mechanics you have not understood quantum mechanics. Quantum mechanics we can do but to understand its weird nature is not easy for our deterministic brain.
Yeah you just made your life more spooky.. like Sir Einstein.
I was literally just watching Only Lovers Left Alive again yesterday and them talking about Entanglement Theory and Einstein’s Spooky Action at a Distance and was trying to look up information on it yesterday but every description I found went over my head.
In sweeps Veritasium to save the day once again!! Lol
You rule bro. Keep it up!!
Thank you! I’ve watched countless videos trying to understand why we can’t just assume they spin opposite from the get go, and finally I understand.
It's confusing no matter how you spin it.
Appleholic1 lololol
xDD
Mind blown 💣
I'll give you one up.
I don't understand any of this, but since it's technically teaching me something, I don't feel bad about not starting my paper on Shakespeare.
+Polly The Parrot that's what I call productination!
+Veritasium how is this paradox different in principle from spinning a coin and immediately knowing the other side is tails/heads? Or spinning two coins with only one face each and looking at one of them?
+beefcake It's different because there is no way you can pre-assign the spin of each particle to get the experimental results for all possible orientations of your spin detector. If the detectors were always in the same direction you'd have a valid point. But they are not. When you "do the math" you end up with the Bell inequality. If the inequality is violated, hidden variables (the pre-assigning of the frequencies of all possible outcomes for all possible detector orientations) are ruled out. Experimentally it's violated, which means it's spooky. And QM correctly predicts the results.
+Polly The Parrot at least you are educating yourself about something that passes most people by without notice instead of learning about old texts that have no real need in today's modern times
Brunneis Ursus Hey, careful what you say about Shakespeare. I wouldn't say there's no need for his works in modern times. Most are antiquated and boring, but he's the father of entertainment. If you're going to study acting or playwriting, you need to understand the origins of the field (That apples to screenwriting, too).
I had studied physics and did not receive such a good explanation during studies. In particular the bell experiment and why there are hidden constants. In the video it is a bit fast (should watch 75% speed 2 times and pause and ponder) but still extremely good. It is not easy, but essential, and the explanation is to the point.
i did a high school project about this exact thing last year, this video came to a better conclusion and was far more understandable than any of the reseach i did over a couple months. thanks for explaining the thing i was meant to explain myself some time ago, i finaly have at least some grasp of how this works now, because even after the project i was still completely clueless on the logic behind it all.
The thing to appreciate is that you tried
I have no idea what this guy is saying. This must be how my mom feels when I try to explain how her iPhone works.
Derek Dufon 😂
He is bad
D E D
Exactly, he contradicted himself at the end
🤣🤣🤣yar.
Particleman... Particleman... does whatever a particle can. Spins around...up or down. Gets entangled. Traverses town...
someone give this man a trophy
+Gabriel Oliveira HOW CAN YOU JUST ASSUME GENDER LIKE THAT
+Kyle Groh Feminist.
+Spassky - Agar.io How is that feminism?
you forgot so look ooooooooout he is particleman
I think if you substitute the word synchronized for entanglement and the word possibility for superposition, it is much easier to understand.
I agree. Some time ago I took to calling them "synced particles."
I was thinking the same thing. The world "entanglement" is misleading.
@@SimplyBergman True, it makes it sound like it is a bunch of mixed-up iPhone chargers
this is the first time ive been able to understand why this doesnt allow for faster than light communication, good job man!
"Spooky spinning particles, send shivers down my spine." - Albert Einstein
This needs more likes😂
We're so sorry particles you're so misunderstood 🎶
The gem of a comment hidden from the world-
finally, a true quote from albert einstein.
albert didn't like small particles, but ironically he got nobel for it..
you just wanted a excuse to wear the spandex
This comment made my day
😂... Or “Wear Spandex and Spin around “
LOL!
Man, I've laughed at every single comment so far
Many thanks for your explanation of Bells theorem regarding quantum theory as it leaves me finally understanding what's really going on.
Once again, you've explained it better than anyone 😁
Thanks 👍
Now I just need a video explaining this video
Thank you to those trying to make sense of this! For clarification:
1. We know the entangled particles must have undefined spins before we measure them because if they didn't they would sometimes give the same spin when measured in a direction perpendicular to their well-defined spins (and they never do).
2. We know the entangled particles can't have hidden information all along about which spin they will give in different directions because if they did we would measure different results at the two detectors >5/9ths of the time and we don't - we only get different results 50% of the time.
3. We can't use this behaviour to communicate faster than light because we can only pick the direction to measure in, we can't force the spin to be up or down - and it will be random with 50/50 probability. When the two detectors pick the same direction to measure in the results at one detector will be random but the opposite random of those measured at the other detector, which is a bit spooky.
However we CAN use it to generate perfect infinite one-time pads. So from a cryptography standpoint it's useful.
What is Factor Relativ to Asymmetry unity??
As its a 50 50 percent chance we cant use the data of up or down but they still gets data so using time intervals we can. a 1 is two ups or downs with a gap after and a 0 is one up or down with a gap after therefore it doesnt matter if its up or down
Can anyone see any problems
isaac heaton It is true that random information is data, but the data in this case isn't originating on either side. We can't tell a particle to be measured a certain way. Even if we had an agreement on which way we should measure them (and in what order), there's no way to impact what the other side sees.
THIS video will REVOLUTIONIZE education!
Finally a good explanation of why there's no hidden information. This question bothered me for quite some time, now it makes perfect sense, thank you
This is the best explanation of spin I've ever seen. Thank you!
This is the best explanation I've seen of Bell's theorem, excellent video
also minutephysics
can you help me to finding anything that connects me to the original RAIF technology. disease (metastatic cancer)
When the words "the opposite random" entered my brain, it exploded.
😂🤣😂
Wow, that is a very smart experience, making use of the both quantum physics and probability... Thanks for sharing!
Wonderful ( even if I get lost sometimes.) Especially notable is when there is an actual painstaking, heart-stopping and ultimately VERIFIABLE demonstration, as in the OTHER Varitasium TH-cams --- "A Physics Prof Bet Me $10,000 I'm Wrong"--- and--- "Risking My Life To Settle A Physics Debate"---. MY Hats off !
I understood 50% of this, and didn't understand 100% of it, so now I too can claim I know a thing or two about quantum mechanics.
Cool! So how do you create an entangled pair?
+aqouby 42
Jos Geerink You get an A+
You could say that you have quantum knowledge and by measuring you are changing it, so no tests for you only A+.
Crazy llama TH-cam comments on science videos are some of the most civilized. It makes you even regain hope for humanity
Quantum mechanics is spooky and often feels like sci-fi. That's why it's so interesting.
That's why you have psi and phi.
@@dhruvinvekariya975 sci phi how did I never see that before :0+--
If we're all indeed living in a simulation, programming quantum entanglement into our counterfeit universe was quite an impressive feat!
wow that's what I wonder as well.. if this is indeed a simulation... those guys up there are super smart beyond our imagination! (obviously)
Or it was a bug that the developers didn't fix because they didn't have sufficient headcount.
It ought to run with 640K for everything!!!
Hard to believe Bostrom's simulation argument is taken seriously. If valid, that is that the odds are overwhelmingly in favour of us being in a simulation given the premise that it is achievable (very questionable), then the same argument applies to the folks who simulated us, and to their simulators on to infinite regress.
@@lindakuttis Will you marry me, Linda Kuttis?
🧡
The spin down sound makes me understand how Dennis felt when he got a wrong answer on Family Fight.
The fact that there's a viable market for this video means I'm dumber than I'd hoped
nooo, maybe you just dont understand fully the market? :)
Why did you hope to be dumb at all, in the first place? ( being exact with the English language on, “I’m dumber than I’d hoped” means you had a hopeful thought on being dumb.lol).
@@mattstevens4192 it could mean that he had hoped to understand spin but doesn't so he is dumber than he hoped. if you understand spin, you're pretty smart.
yes
@@mattstevens4192 bc he's being modest by assuming he was dumb all the time, but not "that dumb" assuming that and making the conclusion about the market of this video actually makes him smarter than he thinks he is. It is the not-dumb actually smart person that maybe don't realize he's smart dilemma.
Sort of
Best explanation I have seen so far without over simplifying it. Thank you.
Following his explaination I could communicate faster than the speed of light (What did I miss? Please explain because this genuinely bothers me)
- Person A gets 100 Particles with spin "up" and Person B gets the 100 entangled partners of those having spin "down".
- Person A and B are many Lightyears apart
- Person A and B have aggreed on measuring the particle's spin regularly at every odd and at every even second respectively (always in their spins current direction)
Sending the message:
- A can measure one time only the spin of their 100 particles perpendicular to the usual direction thus changing the direction of the 100 spins but also of the entangled ones.
- B doesn't know yet that A has measured perpendicular and does the measurement still in his assumed current spin direction. BUT now on avg. 50 spins which were originally "down" will have turned into "up"
- Thus B will know that A has measured perpendicular.
@@csabadunai3760 the problem is we can't make A spin "up", because it has also 50% chance of up or down, so we can't send message to B as we can't control the spin of A nor block particular spins of As. Hope you understood
@@amarnathka2905 he wont, he's just THAT stupid
Narwhal Tamer What's the point in being toxic and calling people stupid?
Agreed. I'm surprised at how many commenters didn't get it. It seems pretty straightforward: particle spin can be up or down, but without getting together to share notes you can't tell whether it's significant or not, so you can't use this for FTL communication. It just begs the question of what's really going on -- which is what good science does, because good science not only provides answers... it breeds more questions.
Please make a new video because recently three people got noble prize for Quantum entanglement and it makes me think that is Einstein's theory really been proven wrong?
As someone who has a background in Physics, I always went along with the accepted point that the randomness within a quantum entangled system prevents FTL communications. I recently read a book 'Cracking the Cosmic Code' which actually shows that the randomness is not a restriction at all. It now opens up the distinct possibilities of FTL communications.
Nothing exposes the inadequacies of the human mind like quantum mechanics.
add beyond. please
That is so vague and sophomoric.
@@hunterliu6620 I think he meant that the human mind cannot contemplate such phenomena.
I know, right? Even searching “spooky action for dummies” hasn’t helped me truly understand it.
Or spandex.
I thought I was the only one who had trouble following this...after reading the comments....*whew* I feel better
no, u r supposed to have no problem following and having problem following this at the same time.
Dummy....
Kidding just kidding
its because 90% of people are braindead or are not even trying
Try watching it a few times. And/or take notes. Maybe look up another individual's explanation of Bell's inequality. Some folk understand one teacher while another understand a different teacher coming at it from a different viewpoint.
The best video so far in explaining quantum entanglement
The mainstream media seem to have an issue with Social Media. Watching YT has engaged me with science more than since school 40 years ago. Stuff like this video has re ignited my mind much more than hearing sound bite news bulletins of fear & misery on repeat every 15 minutes….
Now my head is spinning too!
spin is just a property your head has gained through the course of video, its not actually spinning, don't worry🤣🤣🤣🤣
That means there must be another head somewhere which is spinning in oppsite direction.
That's called a Quantum Headache
Mine's spinning the other way....
@@null-calx lol 🤣🤣🤣🤣🤣🤣🤣🤣🤣🤣🤣🤣
So what I gathered from this video is that quantum mechanics is really f**king confusing
***** And also pretty awesome ;)
***** YES xD
***** the more you think you know the less you actually know. thats the joke at my college and most likely others.
+Matt G
I recently learned that about relativity. I thought I had a pretty good grasp on it but upon further research I found I out was very wrong.
+Matt G More than 5/9 of the time, it is a sign of exponential increase in intelligence.
An explanation of 'spin' I've never heard before. Enlightening and creative. I still can't say I fully understand, but at least I can go to bed with something to ponder.
You could use this to sort of, kind of make it appear like you were communicating faster than light though, at least to a 3rd party: Like say it were a battle situation across the galaxy somehow and you wanted for some reason to be doing the opposite of whatever your allies back home are doing. you could have a pre-planned agreement to let the spins dictate behavior. of course this is not actual communication but it could look like coordination to an outside observer.
A pre-planned agreement i.e. "hidden variables" were ruled out already
"No they're not actually spinning, but they do have angular momentum"
aaaaand I'm lost
it's fine lol apparently no one really knows what spin actually means
@@vanibandodkar31415 it basically means it has momentum, I think. It just doesn't orbit.
@@watertommyz I have problems imagining something that has angular momentum but it's not actually spinning
Maybe they're doing jazzhands
@@LuisSierra42 Generally angular momentum is calculated about a point in space. So, even a particle travelling with a constant velocity, let's say in a direction parallel to the x-axis, has angular momentum with respect to let's say the origin. What angular momentum means here though, is a mistery to me as well. I need to learn more...
Let's say we send a spaceship a lightyear away. On board, there's one particle and we program the spaceship to measure the spin at a specific time. If the spin is up, it destroys itself, if the spin is down, it keeps on flying.
If we measure the spin of the other particle here on earth at the same time, we immediately know whether the spaceship just blew itself up or is still flying - hasn't then information been transmitted?
also a good idea for like instant morse code; and could also probably be used for teleportation of some sort maybe
A hare does not aim accurately as we say in Sweden. No information is carried faster than light, instead the information is carried within the spaceship so to say, more precisely the information how to act upon a certain spin. It is apparent if you think about a little bit closer, the ship could stop to function at any point in the journey and the self destruct could fail for any reason, then the information we have sent with the spaceship ceases to be relevant and no faster than light indication of this is possible. If this happens we can very well be reading a spin up, assuming the spaceship has auto destructed as planned but until some sort of light speed information like electromagnetic radiation reaches us that tells the real tail we are only guessing, we can't know.
You can think of it this way, if we are to go through a labyrinth both at the same time we can entangle our self by saying when given a choice I will always go left and you will always go right. As soon as we make our first decision we lose all knowledge of each other and needs to communicate somehow to know anything about each other. I can however with this information follow you and find your entire path but I need to get this information in real time.
No information was transmitted. You knew state of the other particle by measuring the entangled pair that's all.
You mean: you have assumed that the spaceship blew up based on some expected cause and effect however you couldn't testify in court with certainty that you are now down one spaceship.
The only way to know that it blew up would be to confirm it by observing the ship after the time X, which would again put you under the speed limit.
I heard this been explained multiple time and did not get it... But this video helped me a lot, thanks :D
Sir please make video on "Aspect, Clauser, Zeilinger" 's experiment
The most understandable video I've ever seen about Bell's Inequality. Which is quite a complicated thing. Well Done Derek !
Watching at 75% speed is helpful
thanks
@@ard-janvanetten1331 Bet your turning in your grave and shitting your pants now huh.
thats about the speed of light u talking about
9:14:00 i think this will help.
I watch at 1.75 😂😂 maybe that's why I don't understand some stuff
Dude, i Just can't stop watching this Channel!
Awesome video, but I got a few questions:
How do we know how the two plans are distributed? In the experiment, we can't really tell which plan the particle obeys to until measurement. So let's assume the first plan occurred with probability a and the second with probability b, so a+b = 1. Now we solve the equation a+b*(5/9)=(1/2). All solutions of a and b give distributions of the plans that would result in a 50% chance to measure different spins for the particles...
Second question: What exactly would it mean to measure two entangled particles in two different directions? Is the upwards spin result of the measurement measuring in direction 'up' the same as measuring 'up' sideways? What would we get if we measure the same particle in different directions? The background of this question is: is the measurement still entangled if we measure in two different directions?
im really tired but im putting his comment here so I can read it and try to answer when im not
@@invisibilius1978 Have you already awaken from your slumbers?
@@piepo5002 yeah and I think I get it now though I can't answer because I'm not a quantum physicist. thanks for the reminder I forgot about this
Too advanced for a 15 year old some one help explain?
It's cool, no one gets it.. ;)
I'm twice ur age and I don't get it either
We might have no clue but it sure is interesting tho
You can go checking EPR paradox or Nicolas Gisin's work (quantum teleportation ?) sorry I'm a french speaker so... I can't really explain anything (plus I'm only 18 x)) just ... go check
PS : EPR paradox IS what "Einstein proposed", but he wasn't alone thinking about quantum entanglement so it is proper to talk about Einstein-Podolsky-Rosen
Ok thanks
I feel like I need to watch this video 1000 times to understand it.
You're not the only one.
this guy doesen't explain...he just shows his "intellegence"
this guy is explaining this topic in simplest way possible . You can't expect to understand these stuff without any prior knowledge.
there is a 50/50 chance that you will watch it up and 50/50 chance you'll watch it down. and the results will be different 5/9 of the time and so the results are different only 50% at the time.
and you still won't
I love this video, every university professor should watch this.
I'm more confused than I was before the presentation. There are so many counter-intuitive issues raised and so many statements that need explaining, rather than just having to be accepted as self evident.
I am smarter now. Not sure how, but I am smarter.
Does that mean that someone else got dumber?
Lmao
😂😂😂
Well of course! Wait, what the hell did you say?
The acoustics in that room you are in at the beginning was quite the vibe.
I suppose the many worlds interpretation explains this pretty well. When you measure the particle in one of the three directions, you enter one of the two possible measurement outcomes in that direction (for a total of six possible cases). Whatever your choice, the other particle behaves in the way it has to in that version of the world: it yields an opposite spin in that direction. No faster-than-light action has occurred; you are in the world of a certain specific case, and when you eventually receive information from the measurement result of the other remote particle, it will be the information of that same world.
Quantum physics is the truth of universe and lie of human consciousness saying that it does not need any observer or audience it knows its nature and truth
Specially in quantum entanglement universe is constant it knows what is up or down so where ever the particles go their nature is pre determined its just us making it complicated by knowing it after so many years of evolution
This view isn't as feasible as living in an idealistic world, it's an odd suggestion in favor of materialism that in order to be possible there has to be multiple earths with every single different probability and combination existing on it. But there are billions of billions of humans, with trillions and trillions of cells, all of which go through this same process. Meaning their are billions times billions times billions times trillions of other earths, which is a much more convoluted answer than something that can simply just be explained by idealism which is that reality is a mental construct and doesn't exist independent of observation.
May as well be in japanese.
垂直から60度のスピンを測定するとどうなりますか？
LOOOL
@@jvincent6548 三角法を使うだけです。
@@midhunrajr372 私は知っています - 私はTom Wrightに応答して「皮肉」を使っていました
@@jvincent6548 そして私はあなたに皮肉をされていました。
04:10 You know things get real when the music kicks in.
Song name?
Thank you for your excellent videos! My students so enjoy them. As you look for new video ideas, you might consider doing a follow up on how Bell'st experiment does not rule out hidden variables if Statistical Independence is violated in the case of superdeterminism, which Einstein's block universe perhaps suggests. Basically, the actual measurement taken causes the particles to have been created in a definite way, with hidden variables. Nobel Laurent Sir Roger Penrose suggested in a presentation last year that he didn't think the resulting retro-causality would lead to paradox, if carefully thought through, but I can't seem to wrap my head around it.
That there is what I would describe as a self-satisfying timeline resolution.
“If you can't explain it to a six year old, you don't understand it yourself.”
- Albert Einstein
If you can't explain it to a democrat, you do understand it well.
@@ChristmasEve777 Always a condescending republican in the comments... You should know that everyone is annoyed by people like you. You give republicans a bad name. Luckily my republican friends are not this way.
Please leave politics out of science
@@steffenjensen422 Always a boomer in the comments. you should know that everyone is annoyed by people like you. Luckiely I'm not a boomer, so I can actually make fun of you lmao.
Jokes aside, i hate people that get mad because someone made a silly joke.
@@heisenmountainb6854 I understand that me getting mad instantly is annoying itself.
But I think it's warranted, since this kind of "little joke" is exactly why many people in the US can't communicate normally over party boundaries anymore and you'll probably agree that this is a real problem.
After all, a country where one side will just always try to hinder the other won't progress a lot anymore and will grow weak.
Maybe you're right and I'm overreacting - but maybe this is why we can't have nice things.
Also I'd like to point to this: th-cam.com/video/V-1RhQ1uuQ4/w-d-xo.html
How can I find Jesus in all of this? I'm confused...
Jesus: SpinUp, Satan: Spin Down. There. Yin & Yang....or, does that only create more questions such as religion is only the result of polarity between pairs of matching particle probabilities...the world may never know. :)
Why is Jesus UP and Satan DOWN?
+NYCBG Just kidding, dude. Relax.
ppsayl123 And you thought I was serious??! ROFL.
+NYCBG These days? Who the hell knows. Lol.
definetly one of my favorite videos on youtube.
Who's here after the announcement of nobel prize winners
Having watched many videos on quantum entanglement, I can say that the explanation of john bell's experiment doesn't get better than this.
That is disappointing. Because I didn't understand it.
@@tabby73 the general genius idea is that apparently, if the information for what spins particles must have in which directions is predetermined (or determined at birth) then whatever that rule is, no matter how complicated it is, it must yield some ratio results for all three directions.
For example, 50/50 at a given direction.
So the great idea is, no matter what the rule is, if any rule exists, then the experiment should not match what we really get , which is 50/50
The universe is indeed, a fidget spinner.
XxFoxMotoX3xX 😂😂 Real life understood
Haha maybe❤️😂
and ur comment is indeed trendilly stupid.
albert foxstein
And you are playing with your mind, right now, right? (Your Mom warned you not to do that!)
I always thought this was weird and stupid but turns out the people that told me about it weren’t good at explaining it. Because of this video I finally understand
9 years ago. I got nothing from this video. Your recent videos are way better. Maybe update this one
Dude my head started spinning after 2 mins of watching spin ups and spin downs.
Bell's inequalities are brilliant and mindblowing, with implications that go deeper than most people realize. They tell us that either locality (things are only influenced by their immediate surroundings) is wrong, realism (the moon is there even when you're not looking at it) is wrong, or both. Their most important lesson is that the things you assume, the things which seem like common sense, must themselves be subject to question, because reality might not agree with your assumptions.
No, macroscopic objects like the moon interact gravitationally and electromagnetically with their surroundings and are thus always present whether anyone looks at them or not. "Not looking" means no interaction. Only quantum objects are small enough for that to happen.
***** Realism, to a physicist, means that the properties of a physical system are mind-independent. In most cases, I'd be with you 100% on not applying quantum phenomena to the macroscopic world. But realism isn't a concept from quantum mechanics, it's all over classical mechanics. And we can't say that little things don't exist until we measure them, but the big things composed of them do.
If we accept the mainstream interpretations of QM, like the Copenhagen interpretation, then anything not being measured isn't there, but instead has only a probability of being in any given state when we do decide to measure it. That's weird. But the universe doesn't care about what we're comfortable with.
Matthew Prorok
My point is that macroscopic objects are always being measured. For them not to be measured, you'd have to turn off the moon's gravity and make it not reflect any sunlight, and it would also not have to block cosmic rays etc. Macroscopic objects have too many effects on the environment to behave quantum mechanically.
***** Well, this gets to one of the more difficult points in quantum mechanics, what "measurement" means. That's what Schrödinger's cat is about (which seems relevant here, since it was in making this analogy that he coined the term "entaglement"). What you're doing here is asserting macroscopic realism, which is fine. You can do that; plenty of people do. But it's still an empirical claim that's subject to testing, and Bell's theorem suggests that it could be wrong. As do some experiments involving macroscopic quantum phenomena (i.e. lasers, superfluids, and supercondutivity).
I'm not saying that macroscopic realism is wrong. I don't know whether or not it's wrong; nobody does, which is why it's still a topic of research. I'm saying that we can't assume it's right. And if it is right, then Bell's inequalities tell us that locality must be wrong. (Or, alternately, that we have to sacrifice counterfactual definiteness, the ability to speak meaningfully about the results of experiments we haven't performed yet, as the many-worlds interpretation does.)
***** From the moment it pops into existence, a particle is affected by gravity from everything in the (at least visible) universe, and its tiny gravity would affect other nearby particles and bodies much sooner than the entanglement-breaking measurement takes place. So does gravity not count?
This is the first time I hoped for a science video to end
Now that the Nobel prize 🏆 has been given, relating to this subject, please make a video on the theory's progression.....
There is a third interpretation : when you get the results of the second experiment, you are still measuring a quantum system (whose proper description depends on your results). This interpretation preserves locality, but is observer dependent. It is called relational quantum mechanics.
u don't get many likes because normal people in the comment section cannot understand you, mate!
let me like now and understand later
Oh God, please stop; my brain is full! 🤯
Somce it would be relational it woild be aligned with many aspects of physics
pls check my comments on this video, i think there is relativity. thanks
Jada been doing some spooky action at a distance.
Lmfao
Indeed, the observer (Will) got spooked by how hard she was getting 'entangled' in the distance.
The measurement of the position of the first particle affects the spin , because the other particle will have opposite spin in the same position but measured at a different position the spin can vary as the position of measurement of the first particle and the angle it creates with the position will cause the spin to change
most of this went through my head, have to rewatch it again
"Spooky Action at a Distance" very scientific-sounding name
its actually correct until they find a way to work around the spookiness and encounter a new scientific territory
J.B. - Calling it what it is. Of course, it might not have staying power, and we'll end up with a situation like we have with 'atom,' the name of which was taken from the Greek 'atomos,' which means indivisible. Whoops.
That was the whole point of why Einstein called it that, he wanted to highlight the absurdity of it.
So... Is that clear for everyone? Ok!
Moving on to alchemy...
This is a great explanation! :) it is in deed fascinating science. It starts explaining the unexplainable and yet, the more we discover, the more we understand there is still more and more. The nature of Universe is a constant change and expansion and QM seems to present that. Well, I am not a scientist, but I love to explore the scientific point of view. What is interesting in science is that often it rejects something until it is finally proven by someone. The unseen is vast and miraculous and the more we explore, the more we are amazed. Why? Because it tricks our logical mind so much and force us to wider our perception or reality.
Well defined video although it's such a tough subject!!
Am I getting dumber or was this WAY harder to grasp than any other Veritasium episode? The video ended a few seconds ago and I have no idea what I just watched.
Thumbs up either way for using your 2 million subscriber channel for something like this, rather than yelling over video games or whatever ;)
wooohooo! Yeah this one is way harder than most things I've attempted. I actually made the first version seven months ago but it was impossible to understand, even minutephysics thought so. So I remade it and tried to make it more understandable. It's definitely better than the original.
Veritasium It can't be easy to explain something no one really seems to have figured out yet ;)
Whenever I watch / read something related to quantum mechanics it always just comes across as people thinking out loud. How much of the things you've said here is fact / theory / hypothesis?
Veritasium I think this is the best explanation I've seen of Bell's inequalities ab initio. I work in quantum information though, so I'm coming from the perspective of someone who already knows the material (nevertheless, that means I've also seen a lot of attempted explanations, including some of my own).
racoiaws This is fact, experimentally verified time and time again. The mathematics of quantum physics is well established; the only part people have trouble with is breaking down concepts into everyday language. This should be no surprise, because quantum physics explores regimes which are very far from everyday. We shouldn't expect our spoken language to have the capacity to explain it adequately, nor necessarily for these things to be intuitively graspable.
Quantum physics is possibly our most successful physical theory and none of its predictions have ever been proven wrong in experiment (and believe me, they've been tested).
Bell's Inequality is one of the harder theorems to understand in QM and one which most students struggle. Derek was brave to even attempt an explanation without using any maths! Putting this stuff into layman's terms is difficult but he seems to enjoy the challenge!