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NIST Physicists Show Ion Pairs Perform Enhanced 'Spooky Action'

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Re: NIST Physicists Show Ion Pairs Perform Enhanced 'Spooky Action'

#21

Post by mirimir »

danbruc wrote: post #19
nonbel wrote: post #18

Why does this not describe the "entanglement" phenomenon: 1) Alice, Bob, and Charlie are in a room. 2) Alice has only an apple and a pear, seen by Charlie. 3) Charlie leaves the room. 4) Alice gives one of the two fruits to Bob. 5) Bob leaves the room to meet up with Charlie and starts eating the pear. 6) Charlie instantly knows that Alice has the apple, no matter where she has ended up in the universe (which is not…

Because Bob leaves the room with either an apple or a pear and this choice is made inside the room. In quantum physics Bob would leave the room with half an apple and half a pear, Charlie would ask Bob to eat the pear, and in this moment Bob's half of the apple would teleport to Alice and Alice's half of the pear to Bob. Charlie could also have asked Bob to eat the apple. Very roughly speaking, this picture is actual…

I get how "teleport" isn't QM. But the issue for both is locality violation.

Re: NIST Physicists Show Ion Pairs Perform Enhanced 'Spooky Action'

#22

Post by platz »

danbruc wrote: post #12
platz wrote: post #6

susskind described entanglement in a bit different way than I'd heard - "that entanglement allows one to know everything there is to know about a system of particles (the whole), while knowing nothing about it's parts." In the classical version of an information experiment, if i randomize placement of objects A and B into 2 boxes, and send one of those boxes to someone else - upon opening my box I instantly know whet…

So to me, that doesn't suggest that something "traveled" to the other box, just like in the Classical version. Rather, somehow I only "knew" the system at the beginning without knowing "any of it's parts" (due to entanglement & superposition). Then, just observing a degree of freedom in one the parts finally reveals what the corresponding degree of freedom in the other part was. This (intuitively) makes more sense to…

I'm not sure your description of the difference between classical and quantum contradicts what I said. In fact I think they are compatible

I didn't use any notion of "predetermination" when describing the quantum mechanical version. I said that "there could be several different degrees of freedom to measure on" I meant this to exactly correspond to "the exact outcome is only established when one looks in the first box".

The only notion of "predetermination" I ascribe to is that of the whole system, which is completely described by the quantum states before observation, but as i said this tells us nothing of the parts it's composed of.

(I am choosing in my description to put less emphasis on the particles/parts (which normally get all the attention), and more on the quantum system)

Re: NIST Physicists Show Ion Pairs Perform Enhanced 'Spooky Action'

#23

Post by nonbel »

danbruc wrote: post #19
nonbel wrote: post #18

Why does this not describe the "entanglement" phenomenon: 1) Alice, Bob, and Charlie are in a room. 2) Alice has only an apple and a pear, seen by Charlie. 3) Charlie leaves the room. 4) Alice gives one of the two fruits to Bob. 5) Bob leaves the room to meet up with Charlie and starts eating the pear. 6) Charlie instantly knows that Alice has the apple, no matter where she has ended up in the universe (which is not…

Because Bob leaves the room with either an apple or a pear and this choice is made inside the room. In quantum physics Bob would leave the room with half an apple and half a pear, Charlie would ask Bob to eat the pear, and in this moment Bob's half of the apple would teleport to Alice and Alice's half of the pear to Bob. Charlie could also have asked Bob to eat the apple. Very roughly speaking, this picture is actual…

Thanks,

> "Charlie would ask Bob to eat the pear"

This seems to be the key part. So when they run experiments on this, a certain result can be forced?

> "The important part is that Bob does not leave the room with predetermined fruit."

Right, is this aspect measured somehow or only inferred from the theory?

Re: NIST Physicists Show Ion Pairs Perform Enhanced 'Spooky Action'

#24

Post by mirimir »

M_Grey wrote: post #17
platz wrote: post #15

Earlier quoted context omitted.

sure, but I'm not sure we should be saying that it doesn't have an ontology (even if it is a very weird one), just because the only model that we've been able to come up with thus far is mostly a calculational one (as QM "calculates" probabilities).

It doesn't have an ontology with a current prayer of being falsifies, which is the same thing if you're interested in the science and not the popsci. Exceptions exist, hence AdS/CFT correspondence and M-Theory, but they are exceptions. Even then, all that can be said is various tools have been created with value beyond their fields, not that they're in any way falsifiable yet. At any rate, "intuitive" strikes me as a…

Yeah, that's why QM and I parted ways. I'm too committed to intuition. So it goes.

Re: NIST Physicists Show Ion Pairs Perform Enhanced 'Spooky Action'

#25

Post by danbruc »

nonbel wrote: post #23
danbruc wrote: post #19

Earlier quoted context omitted.

Because Bob leaves the room with either an apple or a pear and this choice is made inside the room. In quantum physics Bob would leave the room with half an apple and half a pear, Charlie would ask Bob to eat the pear, and in this moment Bob's half of the apple would teleport to Alice and Alice's half of the pear to Bob. Charlie could also have asked Bob to eat the apple. Very roughly speaking, this picture is actual…

Thanks, > "Charlie would ask Bob to eat the pear" This seems to be the key part. So when they run experiments on this, a certain result can be forced? > "The important part is that Bob does not leave the room with predetermined fruit." Right, is this aspect measured somehow or only inferred from the theory?

I tried to set this straight in my comment. Charlie does not get to choose the fruit, the fruit is chosen at random. I just allowed Charlie to make the choice to emphasize that the choice happens outside of the room. Had I just said the choice happens at random, then it would not be obvious why this random choice could not also be made in the room with Alice. But then we were back at Bob leaving the room with either an apple or a pear.

Have I look at my other comment with coins in boxes [1], that picture captures the situation better and in a way that is not easily translated to fruits.

[1] https://news.ycombinator.com/item?id=13981054

Re: NIST Physicists Show Ion Pairs Perform Enhanced 'Spooky Action'

#26

Post by beojan »

nonbel wrote: post #18

Why does this not describe the "entanglement" phenomenon: 1) Alice, Bob, and Charlie are in a room. 2) Alice has only an apple and a pear, seen by Charlie. 3) Charlie leaves the room. 4) Alice gives one of the two fruits to Bob. 5) Bob leaves the room to meet up with Charlie and starts eating the pear. 6) Charlie instantly knows that Alice has the apple, no matter where she has ended up in the universe (which is not…

That does describe entanglement. To say that A and B are entangled simply means the state of A is correlated with the state of B. Entanglement is only "spooky" or "weird" because (from Charlie's point of view) Bob is in a superposition of the states |Has Pear> and |Has Apple> between steps 4 and 5.

Re: NIST Physicists Show Ion Pairs Perform Enhanced 'Spooky Action'

#27

Post by roywiggins »

nonbel wrote: post #18

Why does this not describe the "entanglement" phenomenon: 1) Alice, Bob, and Charlie are in a room. 2) Alice has only an apple and a pear, seen by Charlie. 3) Charlie leaves the room. 4) Alice gives one of the two fruits to Bob. 5) Bob leaves the room to meet up with Charlie and starts eating the pear. 6) Charlie instantly knows that Alice has the apple, no matter where she has ended up in the universe (which is not…

Ordinary entanglement is having a strange pair of coins. Toss them both and they will never come up both heads or both tails.

Give one to a friend, walk to the ends of the earth, toss the coin, then call your friend: comparing notes, they've come up different again... spooky!

Maybe the coins colluded when they were made, and there's no spooky action at a distance, just some hidden information inside the coins. This is what the Bell tests disprove. You can make a series of measurements that result in data that could not have been agreed upon by the coins ahead of time.

(In quantum mechanics, the entangled particles are never perfectly correlated or anticorrelated like this, but they coincide or not at a rate much different than ordinary particles)

Re: NIST Physicists Show Ion Pairs Perform Enhanced 'Spooky Action'

#28

Post by komali2 »

mabbo wrote: post #4

> “We are confident that the ions are 67 percent spooky,” said Ting Rei Tan, lead author I love modern physics for lines like this.

I wonder if they were an even spookier 66.6...% spooky, but Ting Rei Tan didn't want to say that cause that'd just be 2spoopy4me

Re: NIST Physicists Show Ion Pairs Perform Enhanced 'Spooky Action'

#29

Post by tedsanders »

danbruc wrote: post #3
headcanon wrote: post #2

One think I've been wondering about spooky action is if entanglement reactions are bound to the speed of light. As in, if one particle of the entangled pair is manipulated, is there a "signal" that is "transmitted" at some speed? Or is it "instant" in the sense that it transcends lightspeed? Or does this question even make sense in this context? Quantum stuff gets weird fast since we have very little basis in which t…

It is instantly but you can not use it to transmit information. Say you have a pair of entangled spins in a superposition of the two anti-parallel states first spin up and second spin down or first spin down and second spin up with equal probability for both states, i.e. each spin is up or down with a probability of 50 % but the two spins always have opposing orientations. If you measure one of the spins, then there…

There is no proof or strong evidence that this occurs instantly. Some interpretations of quantum mechanics still satisfy locality.

https://en.m.wikipedia.org/wiki/Interpretations_of_quantum_m...

Re: NIST Physicists Show Ion Pairs Perform Enhanced 'Spooky Action'

#30

Post by beojan »

danbruc wrote: post #25
nonbel wrote: post #23

Earlier quoted context omitted.

Thanks, > "Charlie would ask Bob to eat the pear" This seems to be the key part. So when they run experiments on this, a certain result can be forced? > "The important part is that Bob does not leave the room with predetermined fruit." Right, is this aspect measured somehow or only inferred from the theory?

I tried to set this straight in my comment. Charlie does not get to choose the fruit, the fruit is chosen at random. I just allowed Charlie to make the choice to emphasize that the choice happens outside of the room. Had I just said the choice happens at random, then it would not be obvious why this random choice could not also be made in the room with Alice. But then we were back at Bob leaving the room with either…

> I just allowed Charlie to make the choice to emphasize that the choice happens outside of the room.

The problem is that allowing Charlie to make the choice allows him to use entanglement to transmit information faster than the speed of light.

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