Scientists Find 'Spooky' Quantum Entanglement Within Individual Protons (space.com) 52
Scientists have discovered that quarks and gluons inside protons are quantum entangled, challenging traditional views of proton structure and revealing a more complex, dynamic system influenced by strong interactions. Space.com reports: Entanglement is the aspect of quantum physics that says two affected particles can instantaneously influence each other's "state" no matter how widely separated they are -- even if they are on opposite sides of the universe. Albert Einstein founded his theories of relativity on the notion that nothing can travel faster than the speed of light, however, something that should preclude the instantaneous nature of entanglement.
As a result, Einstein was so troubled by entanglement he famously described it as "spukhafte Fernwirkung" or "spooky action at a distance." Yet, despite Einstein's skepticism about entanglement, this "spooky" phenomenon has been verified over and over again. Many of those verifications have concerned testing increasing distances over which entanglement can be demonstrated. This new test took the opposite approach, investigating entanglement over a distance of just one quadrillionth of a meter, finding it actually occurs within individual protons.
The team found that the sharing of information that defines entanglement occurs across whole groups of fundamental particles called quarks and gluons within a proton. "Before we did this work, no one had looked at entanglement inside of a proton in experimental high-energy collision data," team member and Brookhaven Lab physicist Zhoudunming Tu said in a statement. "For decades, we've had a traditional view of the proton as a collection of quarks and gluons, and we've been focused on understanding so-called single-particle properties, including how quarks and gluons are distributed inside the proton. "Now, with evidence that quarks and gluons are entangled, this picture has changed. We have a much more complicated, dynamic system." The team's research, the culmination of six years of work, refines scientists' understanding of how entanglement influences the structure of protons. The team's research was published in the journal Reports on Progress in Physics.
As a result, Einstein was so troubled by entanglement he famously described it as "spukhafte Fernwirkung" or "spooky action at a distance." Yet, despite Einstein's skepticism about entanglement, this "spooky" phenomenon has been verified over and over again. Many of those verifications have concerned testing increasing distances over which entanglement can be demonstrated. This new test took the opposite approach, investigating entanglement over a distance of just one quadrillionth of a meter, finding it actually occurs within individual protons.
The team found that the sharing of information that defines entanglement occurs across whole groups of fundamental particles called quarks and gluons within a proton. "Before we did this work, no one had looked at entanglement inside of a proton in experimental high-energy collision data," team member and Brookhaven Lab physicist Zhoudunming Tu said in a statement. "For decades, we've had a traditional view of the proton as a collection of quarks and gluons, and we've been focused on understanding so-called single-particle properties, including how quarks and gluons are distributed inside the proton. "Now, with evidence that quarks and gluons are entangled, this picture has changed. We have a much more complicated, dynamic system." The team's research, the culmination of six years of work, refines scientists' understanding of how entanglement influences the structure of protons. The team's research was published in the journal Reports on Progress in Physics.
Not this shite again... (Score:1)
"Spooky" was the old way to call it before science settled on "quantum entanglement". Actually, it was not just "spooky", but "spooky action at a distance". Update your vocabulary accordingly, "scientific" "journalist" person.
Re:Not this shite again... (Score:5, Informative)
Einstein called it "spooky" because he didn't accept it.
His theory of relativity says that causality can't move faster than light, yet QE has an instantaneous effect across any distance.
So, who was correct?
Both.
In 1964, Aspect's experiment [wikipedia.org] showed that the effect is instant, but no causal information is transmitted.
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I agree with everything that you've said but I want to add that not everybody agrees that Aspect's experiments were sufficient to unambiguously prove Bell's inequality. Since then techniques and instruments have improved. I'm not sure how universally accepted the experimental proof of Bell's inequality is now. (Note that there's a difference between accepting that Bell's inequality holds and accepting that the experimental tests of Bell's inequality rule out any possible, however unlikely, alternative scien
Re:Not this shite again... (Score:4, Interesting)
techniques and instruments have improved.
Yes, they have, and those improved instruments have been used many times to repeat Aspect's experiment. Some of the objections to his methodology have been resolved by later experiments.
"nothing can travel faster than light"
A shadow can move faster than light. But, like entangled particles, a shadow can't transmit information.
what he's actually saying is "information has a maximum speed".
Indeed.
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A shadow can move faster than light.
How do you define momentum of a moving shadow?
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How do you define momentum of a moving shadow?
Momentum is mass times velocity.
A shadow has no mass and, thus, no momentum.
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A photon has no mass, yet it has momentum under the generally accepted relativity theories. https://en.wikipedia.org/wiki/... [wikipedia.org]
Careful. The word mass is used in several different ways in physics, and since physicists usually know which one is used from context, they rarely are specific about which one is being used.
A photon has no rest mass.
Momentum p, energy E, and rest mass m_0 are connected by the relation E^2 =m_0^2c^4 + p^2c^2
(where I put in the subscript "0" to make it completely clear that this is rest mass).
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What if you establish a protocol with a trading partner: if I measure up spin on my entangled photon I buy a stock, otherwise I sell, so my partner can measure his entangled photon at a pre-determined time in a far-off exchange and front-run me for great profit, faster than light can travel between us?
Since neither of us can possibly know what we're going to do before the measurement time, then we do our trades quicker than we can communicate via light, have we profited from FTL information?
We could do the
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How do you profit from front-running your own purchases?
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Simplest way, what if your partner on a far-away exchange buys or sells a thinly-traded stock in enough quantity to move the price, and you on your exchange know from measuring your photon how to react to that purchase before anyone else on your exchange gets the information of what your partner the whale just did?
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That's not "front running".
It's arbitrage.
It's legal. Coordinated transactions on multiple exchanges happen all the time.
There's no need to fake plausible deniability.
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If it's coordinated, can someone figure out the coordination and frontrun your arbitrage (make your trades before you do), but if it uses entangled particles, no one (including you) can possibly know what trades you make before you measure the photon, so no one can frontrun you?
Re:Not this shite again... (Score:5, Interesting)
There are only two possible universes (where the maximum speed of information is the same everywhere), one with infinite speed of transmission of information, where there's universal time (distant clocks can be unambiguously synchronized), and one where there's an upper limit (for all observers), where there cannot be universal time (what Einstein describes).
That is actually not true. That is essentially what you get when employing Occam's razor and ignoring some things. There are more complex possibilities and until we understand what quantum entanglement actually is and how it works, these cannot be ruled out. One thing that is possible is that entangled particle actually get an instant information transfer, but from some third thing that we do not know about at this time. And there is a hint that instant information transfer may actually be possible: The tunnel effect. Of course, tunneling does not scale at all and even getting to a few centimeters takes major energy investment. But it seems like you can transfer information that way and that transfer seems to be instant.
All this means is that we are missing a major piece (or more likely several) of the puzzle and that research is ongoing.
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It is true, there are only two possibilities, a speed limit for information or no speed limit for information. Of course, it's also possible for there to be a speedlimit that is varying, either in time or in space but evidence that that might be true is scant at best. Even the expansion of the universe, where things apparently moved apart faster than the speed of light, doesn't require information to travel faster than the speed of light.
Non-local hidden variables are a possible explanation for entanglement
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No, it is not true. Get some basic insight.
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OK, so what is the third option.
1. There is a speed limit
2. There isn't a speed limit.
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3. A third option. And many more. May be unknown at this time.
Do you know nothing about how Science works? "Tertium non datur" is an Axiom for binary logic, not a fact about reality. Sheesh.
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In 1964, Aspect's experiment [wikipedia.org] showed that the effect is instant, but no causal information is transmitted.
Which essentially just means that we have no clue at all how it works. All ways humans know to synchronize something requires information transfer.
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Which essentially just means that we have no clue at all how it works.
Aspect's experiment didn't tell us how QE works, but it did rule out several hypotheses.
Specifically, the Hidden-variable theories [wikipedia.org] were invalidated.
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IIUC, that should really be "the reasonable hidden variable theories were invalidated". But it's worth remembering that the universe doesn't always work in ways that we consider reasonable. (Just "almost always".)
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Exactly. So far, what we have observed consistently is that physical mechanisms have a strong tendency to complex behavior and lots of factors at work. Some only measurable under more extreme conditions, but always there.
Here is a possibility: Synchronization is via a third thing that comes into play on entanglement. It communicates with both particles but prevents any direct communication between the two. Blatantly obvious to CS people, probably not so much to Physicists. So what we really know at this tim
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Einstein did accept it.
He is one of the main discoverers of it.
He called it Spooky: because he had no idea how to explain it.
Same like no one today has any idea how to explain it.
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Quantum hates binary.
"Particle or wave?" ... Both!
Peanut butter or Chocolate? ... Both!
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/me goes reads "quantum entanglement" in Wikipedia ... huh, as far as I can make out - It seems to be the microscopic workings of conservation of energy.
That's a lot more mundane than I was expecting.
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It seems to be the microscopic workings of conservation of energy.
Not at all. Whether a photon is polarized left or right, the energy is the same.
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Obviously there is more details at the microscopic level. Okay, call it the extension of conservation-of-energy then.
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You can call it anything you want.
But without explaining the nature of your "extension", that doesn't mean anything.
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Very informative of you. Plenty of understanding conveyed there.
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Don't want to pick a fight, but you were the one that invoked "extension of conservation-of-energy", so you are the one that needs to explain what that means. Not sure what other information or understanding is available without that explanation.
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In the case where the spin splits both and and down together that's clearly a conservation. But it's a detail finer than just conserving energy generically.
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I think you may be thinking of particle spin as something spinning, so it would have angular momentum, so from there you assume there is energy and its somehow conserved. But I don't think anything is actually spinning.
Also, think about what would be happening if they were actually spinning, like a wheel. If you have a spinning wheel and magically split it in half perpendicular to the axis of rotation, you have the same energy in the system, the two parts still spin in the same direction, one doesn't sudden
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PS: I'm not trying to make any new definition. I'm just trying to understand what entanglement is. It seems to be an extension of conservation of energy.
Re:Not this shite again... (Score:5, Informative)
I think people are having a real problem with your using "conservation of energy". People aren't outright saying you're wrong because entanglement conserves energy like every other QM process.
Entanglement cannot be understood from a classical PoV, so if you start from there it's doomed to fail.
The conceptual problems come about due to a two-pronged path, only half of which is related to conservation.
The first point is that we have conservation laws - so a spin zero system must always be a spin zero system, a zero momentum system must always be zero momentum etc (and this is where your possible reference to conservation of energy fits in)
What entanglement allows us to do is generate a non-trivial, macroscopically sized QM system. The Aspect experiments, IIRC were of the order of 12m separation of entangled particles, i.e. it would take light of the order of 40ns to travel from one side of the system to the other.
The second point, which is specific to QM and has no classical analogy, is that we have complementary eigenstates. For eigenstate, just think "observable property".
To try and put it into classical terms consider:
Assume an apple can be green or red with equal probability. A tennis ball can be green or red with equal probability.
Assume appleness and colour are complementary states (this makes no sense classically but QM demands it in some contexts)
I have a red object in my bag which is either an apple or a tennis ball with equal probability. In the classical world, if you look in my bag to see whether I have an apple or a tennis ball, at the end you will be able to say either "I have a red apple" or "I have a red tennis ball". But QM doesn't work like that. If you look in the bag to determine the "appleness" of the object in it, you destroy all knowledge of the colour. (and if you measure the colour you destroy all knowledge of the appleness which is why I can say I have a red object but not what type of object it is)
Now back to entanglement. I've now constructed a system such that I have two entangled objects that are complementary and separated from each other. Complementary means that if one is an apple, the other is a tennis ball, if one is red, the other is green (In real QM this complementarity will be because of some conservation law that applies to the whole system). It doesn't matter which attribute you check, if you check the same attribute on both objects (without doing any other checks first) you will ALWAYS get opposite answers.
The first thought is that each object knows both its appleness and its colour but measuring one scrambles the other, that is known as a "local hidden variable". But Bell showed in the 60s that you can make measurements on entangled pairs that give different results if there is a local hidden variable determining both states of the object over there being a global state shared between the two objects. Aspect, and then others, actually did this experiment and showed that Bell's inequality holds and there is no local hidden variable theory consistent with QM
What Aspect did, very cleverly, is managed to create an entangled pair, THEN decide which measurement to make and make it, all in much less than 40ns[1], so that there's no way for the two objects to decide in advance whether to be apple and tennis ball or red and green nor to communicate it between themselves (while keeping to the speed of light)
And that, in a hand-wavy way is sort of what entanglement is all about. Conservation does come in to it but it's only part of the picture.
[1] Assuming that my recollection of the size of his experiment is correct.
Note also that his experiment was also constrained by speed of light, so the two measurements decisions were made independently randomly and in half of his runs he measured "appleness" in one and "colour" in the other so had to discard those results as they gave no useful information at all regarding Bell's inequality. Only in the cases where he, by luck, measured the same property in both particles did he gain information to test Bell's inequality. He couldn't decide in advance what measurement to make because then the entangled particle could have "cheated" when it was created.
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What Aspect did, very cleverly, is managed to create an entangled pair, THEN decide which measurement to make and make it, all in much less than 40ns[1], so that there's no way for the two objects to decide in advance whether to be apple and tennis ball or red and green nor to communicate it between themselves (while keeping to the speed of light)
I love the “choice” aspect of this as it brushes free will. Because the universe could be conspiring (again I love this lol) and force the experimenters to “choose” the right answer to keep things consistent it led to my favorite experiment where it’s not scientists at all but distant quasars [mit.edu] one at one extreme distance billions of light years away and the other in the opposite direction billions of light years away such that neither “exists” yet from the perspecti
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Synchronized separated clocks implies infinite speed of information travel, it's the only way to synchronize them. Relativity dictates that different observers will disagree on whether the clocks are synchronized and even which clock is ahead.
Einstein's paper on special relativity goes into this in glorious detail (and it's not a particularly hard read, just conceptually difficult and once you've got the general idea it makes a lot of sense even if you don't try to follow
Re:Not this shite again... (Score:5, Funny)
"Spooky" was the old way to call it before science settled on "quantum entanglement". Actually, it was not just "spooky", but "spooky action at a distance". Update your vocabulary accordingly, "scientific" "journalist" person.
They can’t update too efficiently, because that would be considered “freaky”.
There’s a two-PhD minimum to unlock that. Not everyone is qualified.
Spooky (Score:2)
with freckles a black nose and a little bowler hat
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Love is kinda crazy with a spooky little proton like you... [youtube.com]
WTF is a quadrillionth of a metre? (Score:2)
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Entanglement is never explained properly (Score:2)
Quantum Disinformation Campaign? (Score:2)
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The Deep Quantum State is running around rigging the news again, resulting in Schrodinger's cat being eaten by quantum Haitians who crossed the space/time boundary without properly interacting with surrounding particles. Some even changed their spin. Something musk be done!