Quantum physics can bring us faster computers, more precise measurements, custom-designed materials, and much more. But the quantum internet is a solution in search of a problem. What is Quantum Internet? Can it really go faster than the speed of light? Do we need it to keep data safe? Let’s have a look.
#science #sciencenews #tech #technews
Post-quantum cryptography would be an interesting video.
QUANTUM-COMPUTING-BIO-ENGINEERING/QUANTUM-COMPUTING-BIO-RECEPTORS/QUANTUM-COMPUTING-AI-BIO-RECEPTORS Could quantum computing be used to solve the issues that are expressed with biological computers, e.g. mushroom and fungi hybrid computers (where the biological components act as receptors that produce complex output signals/information? I believe that quantum computing is such a solution. And then, when such wonders carb be researched and developed upon, they will be used to easily give a biological component to Ai (when the biological component grows and becomes dense, the AI/Android could generate a sense of presence that
I study this field and it's insane how mathematicians and computer scientists could come up with them
I'd also be interested in such a video. How could one show that post quantum cryptography is actually post quantum? Ultimately, all cryptography relies on assumptions on what is and what isn't a hard problem. In the hunt for quantum advantage, we've seen that this is already difficult to decide for classical machines. And ultimately, we don't even know what computation paradigms can even exist. Quantum cryptography may be cumbersome technology, but the fact that it would be robust against all possible computational progress does seem attractive to me.
@@Human_01 Slime mould is pretty good at solving the travelling salesman problem apparently.
Cryptography based on integers is doing fine. There is nothing on the horizon that could change that. Quantum computers are already dying, no reason to pay much attention to that area. Integers are about 6000 years old and there are no signs of them getting rusty. An unbelievable achievement of humanity.
Suggest "Quantum Sabine". Then you can have the cool "QS" acronym, and thus entangled will be correlated with every time 'quantum' is used.
Even if you collapse the wave function she won't know.. at least ... not faster than the speed of light
When you have two socks you never know which one is right and which one is left. Once you put one on your left leg, the other immediately becomes the right one! This happens instantaneously and does not depend on the distance between the legs! Quantum entanglement! It is everywhere!
I know which is which. You are tweaking.
All you did was organize your socks at the expense of energy, while increasing entropy. That's classical and irreversible, not quantum.
I think this has more to do with those hidden variables which have been disproven by Bell's theorem. 🙂
If I put both socks in the drying machine and one of them disapear like it often does, if I put the one left in the dryer on my right foot will the other one become automaticaly a left sock where ever it has been teleported in the Universe?
@@The0ldg0at The washing machine is a wormhole, we always knew that.
I love that Sabine has titled such a topic with "no one needs this", as someone who feels like no one most of the time, I strongly agree!
QUANTUM-COMPUTING-BIO-ENGINEERING/QUANTUM-COMPUTING-BIO-RECEPTORS/QUANTUM-COMPUTING-AI-BIO-RECEPTORS Could quantum computing be used to solve the issues that are expressed with biological computers, e.g. mushroom and fungi hybrid computers (where the biological components act as receptors that produce complex output signals/information? I believe that quantum computing is such a solution. And then, when such wonders carb be researched and developed upon, they will be used to easily give a biological component to Ai (when the biological component grows and becomes dense, the AI/Android could generate a sense of presence that
@@marcelplch8725tf did u do 😂 what character did you use here?
@@rchgmer863 I think he used the "no one" character (empty space) which is what he feels like sometimes.
It took me a while but I came around and understood lol. It's not that sneaky, how did I miss that?
OMG i love how Sabine calls out the BS in quantum public relations. this is the teacher that everyone in the world deserves. thank you.
Needs. I’m in the USA. I’m afraid we get what we deserve.
Quantum PR: The public is simulaneously both happy with us and unhappy with us until we poll a focus group.
@@Shadarebut once you poll the focus group you can’t have both and the act of observing the polling the group may have changed how they felt.
It sounds like what you're saying is that entangled particles are only entangled at the time of their creation which is the time of the collapse of the wave function. So is it the case that the energy of a quantum section of the electromagnetic wave collapses into two opposite (in terms of spin direction.) particles and is this where we get the concept of charge?
QUANTUM-COMPUTING-BIO-ENGINEERING/QUANTUM-COMPUTING-BIO-RECEPTORS/QUANTUM-COMPUTING-AI-BIO-RECEPTORS Could quantum computing be used to solve the issues that are expressed with biological computers, e.g. mushroom and fungi hybrid computers (where the biological components act as receptors that produce complex output signals/information? I believe that quantum computing is such a solution. And then, when such wonders carb be researched and developed upon, they will be used to easily give a biological component to Ai (when the biological component grows and becomes dense, the AI/Android could generate a sense of presence that
I really like your cookie analogy.... I'll be using it in the future. Thanks!
It's a badly flawed analogy. The cookie correlation is classical and therefore obeys Bell's Inequality. But quantum entanglement correlations are stronger, violating Bell's Inequality, which means they aren't just classical correlations.
The properties of the entangled particles are not set before separation, right?
QUANTUM-COMPUTING-BIO-ENGINEERING/QUANTUM-COMPUTING-BIO-RECEPTORS/QUANTUM-COMPUTING-AI-BIO-RECEPTORS Could quantum computing be used to solve the issues that are expressed with biological computers, e.g. mushroom and fungi hybrid computers (where the biological components act as receptors that produce complex output signals/information? I believe that quantum computing is such a solution. And then, when such wonders carb be researched and developed upon, they will be used to easily give a biological component to Ai (when the biological component grows and becomes dense, the AI/Android could generate a sense of presence that
it's not right though. Alain Aspect, John Clauser and Anton Zeilinger won the nobel prize in 2022 for showing that quantum states do change once they have been entangled, even at a distance. I'd share the link to the noble prize website, but my comments get deleted when I share links. If you bite the half of the broken cookie, the other half also gets bitten, even at a distance.
@@Human_01 short introduction: I believe is exactly the opposite of the scientific method. Let me state it that way: Your believes are yours, so no one cares and human rights state no one has to care.
Thank you for confirming some doubts I've had about entanglement for some time. I think you are one of the best popular science communicators of our time. However, you will never persuade me that a rice cake covered in chocolate is a cookie. 😂🤣😂
I'd be careful. As Sabine shows, the fact that "cookie flipping" affects global correlations is not magic at all, but what this example brushes over is that quantum cookies can't have a well-defined break prior to distribution, at least not if you don't drop other common assumptions on how the wprld works.
Still not a cookie. 😜💋@@andramoie
@@jimbenge9649 Fair 😉
@@andramoiecould you dumb that down a little further 😅. I used to believe that nonsense about entangled particles. What should I be believing now?
Check out no communication theorem from Quantum Mechanics.
Wow, der Cookie ❤ Sabine ist einzigartig darin, Sachverhalte klar und verständlich auf den Punkt zu bringen. Danke dafür!
Quantum internet. where you are correct and incorrect at the same time. Seems a lot like old internet
In the old internet, gettng flamed collapsed the waveform and resolved the quantum uncertainty. You can't flame anymore, so we're stuck in continual uncertainty... totally different.
@@tehbonehead i need to open the box to check the veracity of this claim.
One of the worst analogies I've seen.
@@ricomajestic as a lifelong failure no one is surprised you cant comprehend higher thought processes.
@@rhetorical1488 Why are you a lifelong failure? I comprehend everything she said but I just think it is poor. Other people have made the same comment. My analogies are better and I even wrote one in the comments section...look it up!
Although I agree that a quantum internet is not yet feasible, quantum networking may be used to create secure data pipelines, for example between NYSE and CBOE. The transfer may not be encrypted with SSL/TSL/DES. Instead, any attempt to “listen” to the transfer will cause the entire transmission to be corrupted. I encountered this when working with a large brokerage company back in the late 1980s.
I actually got do design the project management plan for a quantum encryption experiment exactly like the one described here for a class in college. We liked to call it quantum read receipts. The experimental apparatus has since made it to the ISS! The biggest problem we had to plan for was, not only that any sufficiently powerful interaction could mess with the quantum states data had been encoded into, but that the crystal lattice used to encode the data into the quantum states itself was also extraordinarily sensitive to vibration. Basically, it works great for encryption… as long as no one messes with the system at all in any way and the flight to space isn’t too bumpy 😅
I appreciate your clarity. Keep up the good work.
You are correct. Reading one entangled particle gives you information about it's pair, but it doesn't change the pair.
doesn't change even though it was undefined before (there is no hidden variable defining it)?
@@Special1122 I believe it's only "undefined" in our minds... it has an absolutely state at any moment in time. The process of "Entangling" particles could be better described as "particle alignment" - but alignment in all properties - likely even ones we're not aware of. Such properties feed functions that determine the state over time. There are underlying mechanisms that describe quantum states - we just don't know what they are and/or can't observe those properties (yet or ever). Hope this makes sense... Also hope I'm right - I hate the idea of an nondeterministic universe.
"Now,when i turn this cookie what happens to the other half?".... 😂😂😂😂😂😂😂 U rock.
The properties of the entangled particles are not set before they are separated so the cookie is nonsense right?
@@ieradossantosCorrect! If you wanted to define definite states for the particles before and after measurement, you would have to admit the only way the correlations observed could be produced is by the particle in an entangled pair updating the other instantaneously upon measurement. This is the nonlocality of Bell's inequality, and the DeBroglie-Bohm interpretation explicitly builds it in. The Copenhagen interpretation prefers to couch this in the language of non realism rather than non locality, denying that such a thing be possible, but it's not clear how denying the existence of particle properties can help us understand the nature of entanglement. Sabine is correct that unitary operations which involve only a single qubit in the pair indeed do not affect the other, but measurement does, and I don't think its a problem that can be simply swept under a rug.
So faster than light communication might be possible? 🤔@@chalichaligha3234
try taking a bite; see if THAT does anything?
@HHMMM-wg6pi Derp! Thank you! No word games, all corrected!
So happy to see someone explain entanglement like this. Seen far too many people explain t incorrectly, causing confusion among people. The analogy is great as well!
The cookie analogy is not a good one. What Bell's inequalities prove is that there is some property of the cookie that is not determined at the break moment, but is randomly chosen by one half of the cookie when it is measured. The other halve immediately stops being random, but assumes one definite state.
@@genseek00 This is only an interpretation of the math and it doesn't change the point the analogy was meant to make (there is no information transfer in entanglement). Plus, local hidden variables can still be true if statistical measurement independence is violated.
Thank you, Sabine. You have absolutely become one of my favourite science communicators. I really love your videos and always learn so much.
Agree with almost everything commented in the video, however I think the title is wrong. What Sabina is adressing are called quantum communications networks. Quantum internet is refered to distributed quantum computation, which has a differenr purpose, and faces different challenges not realated to those cocered un the video
Pardon… but communication between two computers implies a network does it not? And I think the point she’s making is that faster computers don’t necessarily imply a message was received accurately or even to the correct destination (though it may “appear” to have been received).. but I have been incorrect in my assertions and assumptions before, so please correct me if I’m mistaken.
@@dosesandmimoses Rigth, I will extend my reply. Distributed quantum computing doesnt mean quantum communication between two computers. Lets say you have a state of the art quantum computer, which nowadays has a record number of around 1000 qbits. Now we will use some of the qubits of the computer, which are entangled with the rest of the circuit, and we will use them as a “router”. Those qubits then will be entangled with a photon that will be sent to an optical fiber. Through different kinds of protocols, this photon can be used to entangle the qubits of the qcomputer to qubits of a second qcomputer. Once the router qbits are entangled with the qubits of a second qcomputer, you are able to distribute certain calculations between the two computers, so you have an effective computer of 2000 qbits. Extending this setup to a bigger number of computers would form a cluster where you could distribute computations accesing number of qubits way beyobd the state of the art, surpasing the bottle neck of scalability of qcomputers which, up to date, has no reliable solution, (nobody is sure how the current technology will be able to scalate to single computers operating with 10^5 or 10^6 number of qubits). So this computation distribution protocols are what is called quantum internet. Note that this is fundamentally different to just send messages between teo parties, whatever they are, (can be small q circuitz, two computers as you pointed out, or whatever). Just communicating quantum information between two points using quantum cryptography, like quantum key distribution, is called quantum communications, and that is the topic covered in the video, not quantum internet
If you search from google for the term "Quantum internet", the 5 first results don't agree with your definition. It is a bit silly to use the word "internet" if it means something totally different than what it traditionally means.
@@wopmf4345FxFDxdGaa20 Fair enough. I just searched for the term from the University of Chicago defining the term as follows: "The quantum internet is a network of quantum computers that will someday send, compute, and receive information encoded in quantum states." I was suggesting that the term "internet" itself implied at least two computers; you are correct, however, in pointing out that how those computers transmit may or are different than the network communication between general use computers. I did say please correct me if I am incorrect, which you did. However, you did not necessarily explain what the main differences are between general computers and quantum computers. I could have been more thorough in my message; but I was more interested in pointing out that quantum may not necessarily mean more accurate in transmission. As I sometimes say, wormf, learn me (southern for politely teach me.) Thanks for your response!
@@wopmf4345FxFDxdGaa20If people like you weren’t so uneducated then maybe we could refer to conceptualizations publicly in a way that accurately reflects what they do. Regardless.. He’s right you’re wrong.
5:29 Correction, you can't use it for authentication as this protocol already assumes it! You can use it only for encryption of data but not for signatures!
Not entirely correct. I assume you're talking about quantum key distribution, which, as you correctly say, requires authentication. However, the key you generate with qkd can then be used for whatever you want, including authentication.
i really enjoyed the videos with chapters when u talked about several news stories. i miss those and hope they come back
I really remember many videos claiming 'entanglement' was what you described to be wrong. Im a bit sad to find out it was completely wrong, but very thankful for your amazing explanation.
Sabine we need a deeper video on this. I CANNOT remember a single physics video out of the hundreds/thousands I watched over the year that did not clearly miscommunicate the "spooky action" phenomenon. As someone whose only source of physics are these videos and written media that also mostly support this view, I bet there are many out there like me, lets clarify that shit ! Thank you ! :)
She already made a video on the topic last year, titled "why no postals"
@@Thomas-gk42 Made my day, thank you !
@@Thomas-gk42 kzhead.info/sun/m9Skl7SCppGwaZE/bejne.htmlsi=67lbhz0bxPPM6MxC Is this the one by any chance ?
This is one of them(video miscommunicating what the experiments actually imply). She asserts that there is no interaction without being able to refute that very viable and widely adopted explanation. What the experiments demonstrate is exactly that spooky action a distance, some interaction between the entangled particles instead of classical correlation and some "hidden variables". Or the other option which is superdeterminism that Sabine probably promotes. But is much more of an absurd fringe theory than spooky action at a distance, it's not widely accepted among scientists so certainly shouldn't be considered as some "default" explanation. Superdeterminsm is a technical loophole for the experiments, but it hasn't verified any more than the other option so talking like it has, is misleading. Once you actually understand what other things superdeterminism implies, it starts to feel like a conspiracy theory very fast.
@@cyberfunk3793 she has said in a few videos that she favors superdeterminism, if I'm not misremembering. I think her point here is that any thing which may happen "spookly" and "at a distance" is tied to wave-function collapse. And the point still remains that it is not like you'll transfer information faster than light using that.
Thank you for all the time standing up for truth and science and Einstein.
If you look at the history of science in general it's crazy and VERY political. These people are driven by money ultimately. And by the way. Many of them are WRONG all the time.
My nan wnked of einstein!What a stroke of genius😢
I'm not so sure about that. What makes the experimental results so strange is that they actually seem to confirm exactly the type of spooky action at a distance, no mere correleation can explain it. The one loophole to this I'm aware of is superdeterminism which is frankly fairly absurd. Universe conspiring against us generating such correlations that perfectly mimicking interaction without there being it. It's theoretically possible, but certainly not a consensus among phycists.
Fascinating, informative and well presented. Thank you Sabine
An excellent explanation via the cookie analogy, thank you!
"A solution in search of a problem" - basically the mindset approach every tech company right now.
It's a bit disheartening to see a bunch of smart people getting tied up in a race to basically just increase margins by making problems. Hell, a lot of these AI applications being created are kind of in that sphere.
According to bells theorem there is no hidden information (breaking pattern of cookies). The quantum cookies are in a „breaking pattern“ superposition until one is measured.
At least i am happy with the statement that it cannot be used for faster than light communication. Many popular scientific articles suggest otherwise. However maybe Sabine you are willing to explain one more time the difference between Hidden variables and entanglement.
Deosn't matter. If you entangle two particles and send one to earth from moon. The moment people on earth measure the state of the particle the wave functions collapse. After that no change on one will affect the other. Besides how do you want to encode information without collapsing the superposition.
@@heronstreker The fancy word "hidden variables" isn't that complicated. Think Schrödinger's cat. The cat is in the box so we do not know if the cat is dead or alive. Saying it's status is "hidden", implies the cat is either dead or alive, but we just don't know it yet. What really happens is that the cat is neither dead nor alive, that has nothing to do with us not looking inside the box thus not knowing its state. It is not "hidden" from us. The cat is simply in a "superposition" of being both alive and dead. The moment we open the box and look at the cat, the wave function collapses and cat becomes either dead or alive.
I dont particularly care about all the ways that quantum particles are not cookies. As long as the point is true that you can't send information faster than light, then the cookie analogy is good enough for me
Sabine has published multiple papers on Bell's theorem including a loophole that Bell acknowledges. Simply put, Bell's theorem does not rule out hidden variables (see Bohmian mechanics ). It doesn't even rule out *local* hidden variables.
Thanx for the "Little data" - now I have to clean the coffee off my screen!
Thanks for clearing up entanglement with the analogy
The broken cookie analogy is the best description of entanglement I've seen? Thanks for that!
kzhead.info/sun/msqHkdCOgKSagq8/bejne.html
Except it's not entanglement at all, it's just a classical correlation.
The cookie analogy is wrong.
The cookie analogy is not a good one. What Bell's inequalities prove is that there is some property of the cookie that is not determined at the break moment, but is randomly chosen by one half of the cookie when it is measured. The other halve immediately stops being random, but assumes one definite state.
Its terrible and nothing to do with entanglement. I think she was trying to say that nothing "informationy" is travelling between the cookie halves
why is entanglement always explained by using hidden variables? it is just wrong xD those cookie halves in this example do not have a definitive break up pattern until later. this break up pattern is in a superposition of all possible patterns until you look at them. when you look at one of them, this superposition "collapses" to one definite pattern, and the second cookie will - somehow - have a matching one. that's the whole point and the mysterious part of entanglement. if they had this pattern from the beginning this would be indeed as trivial, as it sounds here. it also would mean hidden variables, which is not what is happening in the standard qm. and no, waving with hands and calling on the correlation gods doesn't help. it is exactly the funny part how they can stay correlated without hidden variables.
Doesn't do much practical good though, as the collapse cannot be detected without inducing it. You can use entanglement to generate correlated randomness at two locations like that, but you can't use it for communication.
@@vylbird8014the distinction between the mechanics of wavefunction collapse and predetermined local hidden variables is exactly what Bell's inequality describes, and experiments have confirmed.
Your explanation of entanglement is great needed clarification. The particles in the entangled pair do not interact physically. If that where so, we could build "entangled smartphones" which need no communication media, and would communicate instantly across any distance.
Not sure one could claim there is no interaction. An entangled pair has some random property that is not definite before the measurement is done. Once it is done on one particle of the pair, the other particle is not random any more, but in a definite state.
I love the metaphor of quantum entanglement as being the two halves of a cookie. This is something that seems to be frequently misinterpreted (including by me), so gaining some clarity on how this works from you is fascinating. Thank you as always!
Thanks for another fascinating video, Sabine! 🙂
Hi Sabine. I love your videos. About the cookie analogy. I think there's a problem with it. As you say, if you interact with one particle nothing will happen to the other, but IMO that's not where the faster-than-light paradox lies. The problem is the collapse of the wave function. The cookie analogy describes a correlation via the break pattern, but a break pattern is definite, so it's either analogous to the entire wave function, which you can't measure and doesn't contain the information relating to the actual measurement, or to a hidden variable, which we know doesn't exist. It seems that if you measure one of the particles their combined wave function collapses, meaning that the distant particle has a definite whatever-you-measured. Perhaps this is not a problem because the wave function itself is not measurable, only the eigenvalues, and portions of this function could move faster than light without trouble so long as the effects do not pass this limit. A thought experiment: send particles A and B in opposite directions at nearly the speed of light. Then, when they are outside each other's light cone measure one and perform the double slit experiment on the other. Will you see an interference pattern or not?
thank you so much clarifying this common misconception
Thanks Sabina. Week by week I get clearer understanding of spooky physics.
Can you do an episode about the science in the sci-fi series "Three-Body Problem"? I am especially interested in the part about the more advanced aliens having created a computer the size of a proton, with sufficient technological advancement and the additional dimensions as mentioned in the story. In the story there are two of these computers, entangled, so that the distance of 4 light-years is not a problem for the aliens. It's interesting the writers apparently omit what you just explained, but I would love to know if the rest of it is possible.
You should have put a spoiler alert at the start of your comment. No point watching it now.
Should have had a spoiler warning. But that is a small fragment of a much deeper and broader story. Very much worth watching.
Spoiler warning follows: It's science fiction, not existing science. The bit about unfolding a proton and building a computer inside it is based on the dimension aspects of string theory. String theory is not proven science, and in fact hardly anyone studies it now. It's an old theory that went nowhere, but is still popular in science fiction and popular science books. So whilst the science in the series is based on scientific theories, it's all fringe science that hasn't gone anywhere, it's not real.
The Quantum Internet. So people can have an On Line argument and agreement in superposition.
No, you’re wrong. Yes you’re right. Are we quantum yet?
It'll just be used for porn like every thing else 😂
Some people do this already.
This is not correct. The Internet collapsed into an argument-only state in the early 1970s.
It's amazing how much I learn from your channel. I left this video with a completely different understanding of quantum entanglement. I've done lots of searching on KZhead about it seems the majority of people exaggerate details for engagement instead of being fully honest. It's also highly possible they were also getting misleading information. Thank you for for explaining the real science in a way that average people can I understand.
All of your content is extremely interesting, not just the quantum stuff
The cookie analogy is a great explainer; measuring one particle doesn't change the other it just gives you the answer to what the other will be when you go up to that one and measure it too
The cookie analogy is not a good one. What Bell's inequalities prove is that there is some property of the cookie that is not determined at the break moment, but is randomly chosen by one half of the cookie when it is measured. The other halve immediately stops being random, but assumes one definite state.
I have heard that there was any experiment to determine if "the cookie" was broken in half, or if the cookie in fact only decided what half after one was checked. It turned out that this was only decided afterward, not because of it being decided beforehand.
That's besides the point. You still can't send information with it, and the entanglement still has to happen locally. I.e. the fracturing of the cookie has to happen locally, but it only determines which half is which once they're measured.
@@Forty2de No, the point was to correct her statement of the "cookie half" being decided on the production point, when the decision is first happening at a distance. :-) The part about information not moving faster than light is also not that simple. It assumes that light has no weight and that is not determined yet, secondly has a new experiment maybe shown that light can interfere with itself backwards in time. Lastly, am glad you are saying "information" instead of "nothing can" because light is not the speed limit, it may be the information limit. :-)
There is no such experiment. Those types of experiments are based on particular interpretations of the events that occur, but alternative assumptions lead to different interpretations and the mystery evaporates. Sabine has done multiple videos on these sorts of experiments and explained how the quantum mysteries are a mirage.
@@naasking I assume you are trolling right now:-) Of cause there is such an experiment, it is a double slit experiment, but done in time, and it makes interference patterns with one slit. Maybe you should try to search for newly done experiments, and who they are made by. There are no question about quantum being far out and nobody understands it, but that does not mean you can't make scientifically sound experiments. It does only mean that we do not know why and how it behaves like it does.
@@friedmule5403 The double slit time diffraction experiment is not saying what you think it's saying. The interference pattern is not created in spatial dimensions but in the frequency domain. This is an interesting result, but not a challenge to any interpretation of quantum mechanics, including local ones.
The cookie example is genius. I finally understood it after a decade 😂
It's actually not a good analogy. The properties of the entangled particles are not set before they are separated.
@@FLPhotoCatcher Which is exactly what she demonstrated.
@@FLPhotoCatcheri was thinking the same thing. There’s no predetermined value that signifies when they should break
Well, no it isn't. It assumes super-determiism, which is not science.
The cookie example means "Entanglement" [amongst scientists], or simply the other entangled parties who are making money faking a concept have to share it like sharing the cookie to legitimize it.
Thanks Sabine, best laugh I've had all day. I've marked your starting point about entanglement and will be distributing this as the best simplification I've yet seen that even 3 Body Problem fans should be able to grok
Got a real kick of out the 'Little Data', nice work.
1:19 to 2:29 - This seems really misleading. Bell's theorem seems to strongly suggest that the relevant correlated properties were not "built-in" from the beginning prior to the measurement. Edit: The above roughly refers to Bell's theorem suggesting that local hidden variables theory is false. While one could make a logically consistent case for something relevantly similar to it being to true, this is controversial at best, thus rendering Sabine's "this is just wrong" comment misleading.
Right. The cookie correlation obeys Bell's Inequality and is called "classical," but quantum entanglement correlations are stronger... they violate Bell's Inequality.
I seem to recall that she has said elsewhere that Bell's Inequality has not ruled out hidden variables.
@MagruderSpoots Indeed, Bell's Theorem is also a misunderstood concept. Sabine has a great video on it. Bottom line, anything with a "woo woo" interpretation can be safely assumed to be misunderstood, including (especially) QM.
@@MagruderSpoots To oversimplify somewhat, hidden variables aren't compatible with locality.
>MagruderSpoots : Yes, one frequent misinterpretation of Bell's Theorem is that it rules out "hidden variable" interpretations of QM. It only rules out interpretations that use LOCAL hidden variables to explain the strong entanglement correlations. NONLOCAL hidden variables have NOT been ruled out. In other words, Bell's Theorem shows that QM violates either the Locality assumption (nothing can be influenced by anything outside its past lightcone) or the Reality assumption (things have definite properties before the properties are measured). Note: Sabine & Tim Palmer have pointed out that the Superdeterminism assumption would allow both Locality and Reality. But they lack a plausible explanation why Alice & Bob always observe entanglement's strong correlations no matter how hard they try to orient their detectors as randomly (or pseudorandomly) as they can, and I don't know of anyone serious who thinks Superdeterminism is plausible. At best, we can say that Superdeterminism is an incomplete explanation of the observed strong correlations... even less complete than Materialism's explanation of conscious experience. To account for why the strong correlations are always observed in Bell tests is Superdeterminism's "hard problem."
There's something fishy about this cookie analogy. Everything about the cookie halves' states is determined when they're separated, whereas the entangled particles are in superposition which ends for both with the measurement of one. Isn't this a case of Sabine sneaking in her own pet interpretation under the cookie...I mean radar?
The point that she is trying to make is that while local manipulation results in a new global quantum state, this doesn't mean that this local manipulation has a measurable effect on the other half of the entangled pair. You just change the kind of correlation. I'd argue that this is pretty much undisputed. The claim that the halves had a definitive state prior to separation, is not compatible with our observations, except if you postulate that measurement settings cannot be chosen "freely" by the scientists that investigate the two halves. Sabine prefers the notion that there is no "free choice" which is consistent, but certainly not undisputed. I would reject this idea, not on the grounds that I claim to know how reality works in this aspect, but because I feel that physics should describe our expectation of measurement outcomes given our previous observations. The moment that we declare that the question "What would we expect if we measure this and this?" is essentially not valid, because we cannot freely decide which measurement to perform, this doesn't seem to be physics anymore, at least to me.
I agree. The analogy works because she sneaks in her rejection of measurement independence, which is fine with enough context, but a science communicator may want to be careful about implying interpretations that are not widely accepted.
The only part where it gets funky, as far as I understand, is that depending on how you measure the entangled particle you get different results. That means that if you could collect a lot of entangled particles and measure them so that you get skewed results on one side, then that would mean the particles on the other side will be the opposite, which might be useful to convey information.
Correct about the skewness. But no information whatsoever could be transmitted this way. There is a theorem in Quantum Mechanics called no communication theorem. Check it out.
I recall reading a Sunday supplement in the 1960s about the newly developed ruby laser. The headline was "A solution in search of a problem". Spin forward 20 years and CDs are replacing cassette tapes; another 30 years and what doesn't use lasers?
Yeah and the guy who invented it was awarded $300. Something is wrong there....
Your cookie analogy is equivalent to the Hidden variable theorum which has effectively been proven wrong at this point. It assumes that the correlation of the break is known beforehand. Bell tests have shown that the "break" doesn't actually happen until the first measurement is made.
But Bell himself said he couldn't rule out a hidden variable explanation because the inequality relies on certain assumptions which can be violated.
@@audiodead7302 There has been significant progress in the tests since the 1970s. It's pretty well accepted that the most recent series of loophole free tests have dismissed the possibility for hidden variable theory to be accurate.
If the variable is hidden or not does not change the fact that after the first measurement nothing will change any state anymore. That is the crucial part of information transfer. Which does not happen neither in wave function/superposition nor in hidden variable theorems. It's useless.
@@ArseneGray You mean after the first measurement they will no longer be entangled right? You can always change the state... But yea, I agree that there is no useful information transfer there as any knowledge "gained" during the measurement was established as the time the particles were entangled. I don't think it's useless. It's a good "information seal" to detect 3rd party interefence. I don't see much of a use for it beyond that yet though.
@@MM3Soapgoblin No no they are still entangled, but measuring the spin of an electron for an example is not the same thing as changing the spin of an electron. When they are entangled we can indeed measure entangled spins but the moment we want to decide which spin the electron should have, so "change" it the way we want it , the entanglement does not work anymore. measuring states is useless, if we cannot alter the states on purpose to encode information. It can be useful in any other ways but FTL communication is just a myth.
There is a theorem in Quantum Mechanics that is called no communication theorem. It proves that entanglement does not allow information transmitted faster than light (clarification: it does not allow us to use it to transmit information faster than light). I really do not understand why so many people (incl. physicists) believe that entanglement could transmit information instantaneously.
In another video, Sabine talks about Einstein's spooky action at a distance as working even with a single particle/wave, with no entanglement between two particles involved. Einstein was concerned about how two different spots of a screen hit by quantum waves in a double slit experiment are mysteriously connected; if the particle arrives in a bright stripe in the interference fringe, how could other spots know that the wave was no longer there, it disappeared or decohered "instantaneously" when the particle hit the screen and became a collapsed measurement. There is no physical theory or equation explaining this process of decoherence, and quantum theory doesn't provide one. You just have to accept the Born rule on faith, it is not accounted for in the theory.
@@fbkintanar thanks for this addition. Yet, in your scenario no information can be transmitted, even though decoherence happens with the whole wave function instantaneously.
@genseek00 Because it does just that. That fact that the theory does not provide a way to use non-locality is beside the point. If no information were transferred, the correlations measured would be impossible. See Bell's theorem.
@@carlhitchon1009 it does not allow us to transmit information. What the system is doing within itself and whether it transmits information to uphold the correlation (Bell's inequalities) is up to the semantics. We can call it "information transfer" if we so desire (although I personally would not do it to avoid any further confusions and misinterpretations), but we cannot use it to transmit information.
5:23 "Little Data" had me rolling on the floor laughing my positronic ass off!
Smooth as Riker's freshly shaven face?
I think the best explanation of the entanglement involves a pair of shoes. We send one shoe to both Alice and Bob. The moment Alice opens her package with the left shoe, she knows Bob got the right one even if he is now on a planet in the Alpha Centauri system.
You can use the same example with gloves
now you've taken the shoes out of the box; the litter box.
But again, there´s a difference between the handedness of the shoes, that is clear , before you send them, and entangled but unmeasured particles, Sabine pointed that out in her video "Why No Portals" from last year, where she used your example.
Try this with socks, my bad if it breaks the Universe.
@@Thomas-gk42 Yes, the analogy is not perfect. With quanta, there is no person who sends the shoes (or gloves) and knows which is which. But it is still the best analogy.
Sabine, I apologize for what may seem like a somewhat pedantic point but since you happened to make a claim like this insome of your previous videos as well, let me clarify that alternative "quantum safe" cryptosystems like lattice-based cryptography are not actually *known* to be safe from quantum attacks. We have no actual proof that they are any safer than classical tools, the only difference is that we have not found any way to exploit quantum methods to crack them more easily. I'm sure you of all people can best appreciate the difference between knowing something being impossible and merely not knowing how to do something. You may be interested in the story of SIKE cryptosystem, long believed to be quantum safe, which has been cracked in 2022 (not even using quantum stuff). Post-quantum cryptography is still a young area so we may be in for many more surprises like this.
Same thing goes for quantum / classical computing in general - we know of quantum algorithms where we don't know of an equivalent classical algorithm - but we have no evidence that similar classical algorithms can't exist.
Mathematech approved, I have often used the same broken cookie analogy when explaining entanglement. The only difference is that macroscopic cookie states are completely described by points in R^n for some large n, but complete specification of electron spin requires a function defined on a sphere and how one measures sizes of sets of these functions depends on context, so spin statistics is more complicated than a single joint probability distribution.
Great video as always Sabine. Thanks
Your cookie analogy is incomplete. In quantum theory, each individual cookie half exists as a superposition of right and left-hand pieces so each half can be observed as either right or left-handed. Whichever hand a given piece is observed to have the other piece will automatically have the opposite hand. So something "spooky" is indeed going on and Einstein, who was no slouch, was freaked out about it.
Do we know that the cookie *exists as* a superposition, or is that just the model of the cookie that represents our knowledge of possible measurement results?
All "superposition" is is a *probability distribution*. 50% probability of measuring right, 50% probability of measuring left. Correct me if I'm wrong.
You may not know whether you have the right or left hand piece of the cookie, just that the other piece has opposite properties in some way. Thus the quantum mystery is preserved in that you do not have a complete understanding of the whole object but you can infer that the edge will exactly match your edge. No matter what you do with your piece of cookie will not affect the other piece so long as it is some distance away.
Classical correlations (which Sabine illustrated using a cookie broken into two parts) obey Bell's Inequality. But quantum entanglement creates stronger correlations, which violate Bell's Inequality. Sabine shouldn't mislead her viewers by saying quantum entanglement behaves classically.
Thanks for the video
Well done, Sabine. I approve. Always a pleasure to watch your explanations.
No, the actual problem of encryption is that it cannot be mathematically proven. All encryption proofs rely on the assumption that some problem is hard just because no one solved it yet. The military doesn't like that, and because of that they even still use the One Time Pad, because while very annoying is actually proven to be secure.
I'd like Strategic Ambiguity to be renamed to Quantum Politics.
Marvelous explanation. Intuitively, i knew what she said, but it's good to see someone with credibility to confirm and break myths.
Thank you very much for clearing up how entangled particles actually behave. I had believed that interactions were faster than light although I was aware that information could not be passed between the two at such velocities. You're the best!!! 😁
Unfortunately what she said was misleading, because while she is correct that performing an operation on one of the entangled particles doesn't affect the other, this is not true if measurement is involved and she admits that Einstein described it as spooky. Measurement happens all the time and is a huge problem in the foundations of quantum mechanics. If you ascribe definite properties to the two particles in an entangled pair before and after measurement then you must conclude that they update each other instantaneously. This is Bell's theorem that has been experimentally confirmed. The fact that you can perform special (unitary) operations on one of the entangled pair without affecting the other as Sabine says is besides the point, that is not the mystery.
Hahahahah "Little Data".
2:27 But you can map out the other cookie's break line (faster than the speed of light at spookie distances), even after turning the first half cookie over.
Thank you for the explanation of non local correlation.
2:35 - If turn one side of the cookie upside-down what happens to the other half - is not not nothing. The other half keeps information of the initial state of both entangled particles - which are: braking pattern, weight, shape, structural strength and ingredients of a cookie, reading this information still possible even if the first particle is disentangled, loss, stolen or (eaten)annihilated. This may not be very handy for information transfer but is very handy for verification of packages for example. I see potential value in faster TCP protocols, better data encryption or something like that. Very few humans on Earth have actual quantum computers, even fewer have lab equipment that can read particles entanglement. It has something in it.
Sabine, I remember the Sinclair Quantum Leap conputer years ago. Enough said! Which turned out to be a lot of hype (though ine of my favourite computers). All corrected now.
From the applied perspective (and I speak with less experience than most) the majority of security breaches can be tied back to human error. Part of this is because you *can* crack a lot of cryptographic hashes given time, the issue more becomes that it just literally stops making sense after a while and no longer becomes worth the adversaries time. I remember hearing about this on a podcast and was sort of disappointed the interviewer didn't press that issue because, at least with classical computers, even large data breaches are more defined by human error (exploits in software, people leaving their credentials in open areas, sharing info with people, etc.)
Sounds like the use case would be only for data transfer that absolutely needs to be ultra secure where it is preferable the data is destroyed rather than intercepted.
"A solution in search of a problem" Genius!
Yes, thanks so much for your channel. I hope all your hard work will pay off. I really feel like you deserve it!
Regarding the entangled particle misconception; I was led to believe that there really is an instantaneous exchange of 'information', but that it couldn't be used to send 'real information' because we cannot control whether a particle will measure spin up or down.
Love your content for a long time now. Oddly, I just noticed I have been unsubscribed from your channel. Very odd.. I was wondering why I hadn't seen your videos pop up for the past few months.
ONce again you have clearified my understanding and crushed my dreams all in one stroke lol.
5:56 Saw what you did there with your hair! 😊❤
The way I understood it in my basic way was; by checking if 1 entangled particle is negative or posative it instantly reveals the other particles polarity. So with the cookie analogy, we could cut 1 trillion cookies in half and put them in labeled boxes, send them across the galaxy and use it as a way to comunicate instantly just by opening certain boxes here to send a message while they check what boxes are open to read the message.
4:45 "a measurement [of a quantum state] is really any sufficiently strong interaction that causes decoherence" . This may be common usage in certain parts of physics, but it seems to bears little relationship to the notion of measurement used in the rest of science. I would think a measurement, in addition to an interaction between a probe and a supposedly isolated system under study, should also involve a connection that amplifies a signal generated at the probe to produce a meaningful change in a display that reflects the interaction. A measurement setup needs to be designed with a limited number of target properties and tunable parameters in certain finite ranges and granularities of resolution. The setup and display readings need to be calibrated relative to other measurements according to a governing theory, every run of the setup needs a preparation, and individual measurements are seldom meaningful in characterizing individual physical events, it takes a statistically relevant number of repetitions of some event type. Unfortunately, when physicists discuss foundational problems like "the measurement problem" to a wider audience, this distinction is blurred, resulting in confusion in the audience. It seems there is a narrow foundational measurement problem 1, which is to come up with a physical explanation of decoherence, complete with equations and empirical measurements. That is related to but distinct from broader measurement problem 2, which is to model how actual macroscale measurement devices work when probing at a scale where quantum effects are not overwhelmed by classical counterparts. This is what is on the minds of many chemists and molecular biologists who look to the physicists for guidance, I guess this is more the theoretical grounding of instrumentation physics, rather than an earth-shaking problem that would generate one or more Nobel prizes if it were solved. But if quantum sensing and quantum computing are to become more important in the future, I hope there can be clearer explanations of measurement problems 2, even inf **the** measurement problem 1 remains unsolved.
of course you need to fully understand entanglement and if it is exactly as reported then I would agree, but there is a chance that something known is proprietary. In that case we may have to wait.
Not to mention, you need regular relays to either route or boost the signal, and those have no such magical anti-tamper properties.
The cookie comparison reminds me of the socks comparison (Bertlmann's socks I think). Short version: If you have the left sock then you now the other one must have the right sock. The problem: This comparison is usually used to tell that the socks comparison is wrong (or in this case the cookie comparison would be wrong according to that same logic).
I believe you are correct, Sabina. Well done and could be educational for those doing head spins lol. Peace ✌️ 😎.
I think the source of the problem for why FTL Quantum communication is probably not possible is because, as Sabine pointed out, to entangle particles they need to initially contact eachother locally and once you measure their states the entanglement is broken - otherwise you could in theory have a matrix of entangled particles with pre-assigned meanings for communicattions. But the once you measure it your quantim cans on strings setup is broken is the deal-breaker for this hypothetical setup
Another way i heard this explained was even if entangled particles could have their states changed simultaneously at a great distance, you would still need to communicate the state change/s between the sender and receiver and this would be at best at the speed of light in a vacuum
I think of quantum entanglement like a pair of gloves. If you see a left hand glove you'll automatically know the other is a right hand glove. However if you remake one glove into something else it does not change the other glove.
No. Study Bell's Theorem, which shows that entanglement correlations are stronger than classical (cookie type) correlations. The 2021 Nobel Prize was awarded for the experiments that confirmed Bell's Inequality is violated by quantum entanglement. Sabine's video is very misleading.
@@brothermine2292 You are right, unfortunately this argument is often biased.
"a solution in search of a problem" is craazyy 💀
Excellent way of explaining with the cookies. Star Trek was great but it made everyone start talking about breaking the speed of light barrier.
Quantum entanglement isn't a link, there's no more action or information than writing the same thing on two bits of paper and putting them in sealed envelopes. "Entanglement" is local, then things move away and don't change until you mess with them again. Open the envelopes a thousand miles away at the same instant and you aren't sending information faster than light. You're just revealing info that's already traveled. Burn it, write on it, open it early - you break "entanglement." Honestly it probably just means the probabilistic model of quantum physics is based on a deterministic universe with a lack of data on our part. (Some people hate that thought, because even though it wouldn't disprove something close to a multiversal model, it wouldn't exist because of our branching decisions or anything cool like that. It's just that in that model it happens because infinity is so big, and in an infinite number and amount of big bangs this will all happen again, in every permeation it is possible for it to happen, which doesn't include branching and doubling the matter and energy that exists into an infinite number of dimensions, or instantly jumping to other copies of earth that would be as close to infinitely far away in space and time as it is possible to be in this model, or physics working differently, or anything silly like that.)
Thanks Sabine! You're a breath of fresh air.🌞
Love the editing where you seem to ripple. I treasure moments that remind us not to be so serious 😅
Thank you for the video. Little Data.... that did indeed amuse me. Peaceful Skies.
Wow I understand, thanks Sabine.
2:10 YES. This is exactly how I’ve described it to other people who think it’s all “spooky”. Quite frankly entangling particles is no different than hitting two pool balls together. If you know the start states and then measure one then you *know* the other. That’s all.
I sometimes think information (quantum or classical) is what it is immediately everywhere. But that does not mean it propagates (say via a spacetime geodesic) immediately from origin to anywhere. And I see no contradiction. The broken cookie example is a good one. It is broken independent of spacetime. Perhaps it takes some time to figure this thruth out remotely (maybe via photons at the speed of light) but that is not an information problem, it is a communication problem.
Sehr gut Sabine 🎉🎉🎉🎉…!
في المستقبل البعيد وبفضل التكنولوجيا المتقدمة سوف يتساوى الخيال مع الواقع ويمتلك الإنسان قوى الآلهة ليحول الكون والأكوان المتعددة إلى جنة خالدة ❤
Wow, Sabine, HUUGE thanks to you for calling out the BS about entanglement! Causality - YES!, decoherence - YES! "spooky action at the distance" - NO! You wouldn't believe of how many amateur and professional quantum researchers are misleading themselves and others when talking about these topics!
Isn't the cookie analogy an example of "hidden variables" - which in this case would describe the exact profile of the break - that Bell's Theorem (and subsequent experiments) have ruled out? Isn't the predetermined and conserved break profile an example of 'local realism' that has been conclusively disproven at this point? If quantum data transmission was merely a matter of preserving correlation relationships, what prevents a man-in-the-middle attack where the attacker measures the polarization and phase of each intercepted photon from the sender, and then manufactures and transmits an exact clone of that photon (with those same properties) to the receiver? Then, both the attacker and the receiver will have observed the exact same series of measurements, as the receiver would have observed if the attacker wasn't there at all...
Photon packets are at a high throughput. I used to see the plumbing they would do for MW signal processing.
Thanks for the discount code