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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'

#51

Post by platz »

intrasight wrote: post #50
danbruc wrote: post #48

Earlier quoted context omitted.

I have no idea what you mean, there are obviously particles, we have an entire standard model full of them.

https://news.ycombinator.com/item?id=12377393 My understanding is that there is a growing consensus on this

Just because "Particles are epiphenomena arising from fields." You are completely missing the point that the bumps in the field are what we call particles. There can be distances between the bumps/particles and that means that the bumps are "separated", because it matters whether the bumps are next to each other or far away... This is what we mean by separation. No one is saying the field itself doesn't fill all of space (which it does)

Furthermore you can still speak of particles just as you can speak of atoms, because it's useful to call the bumps something other than bumps all the time.

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

#52

Post by intrasight »

platz wrote: post #51
intrasight wrote: post #50

Earlier quoted context omitted.

https://news.ycombinator.com/item?id=12377393 My understanding is that there is a growing consensus on this

Just because "Particles are epiphenomena arising from fields." You are completely missing the point that the bumps in the field are what we call particles. There can be distances between the bumps/particles and that means that the bumps are "separated", because it matters whether the bumps are next to each other or far away... This is what we mean by separation. No one is saying the field itself doesn't fill all of s…

But there are only "bumps" when observed, right?

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

#53

Post by platz »

intrasight wrote: post #52
platz wrote: post #51

Earlier quoted context omitted.

Just because "Particles are epiphenomena arising from fields." You are completely missing the point that the bumps in the field are what we call particles. There can be distances between the bumps/particles and that means that the bumps are "separated", because it matters whether the bumps are next to each other or far away... This is what we mean by separation. No one is saying the field itself doesn't fill all of s…

But there are only "bumps" when observed, right?

no-one knows what is really "there" when unobserved. fields don't get us out of having to interpret the wave equation (the wave equation is a whole different kind of "waviness", it's not the same thing as the field); and the wave equation only lets us calculate probabilities. so we don't know. but it's true that some things don't behave like particles when we're not looking.

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

#54

Post by danbruc »

intrasight wrote: post #50
danbruc wrote: post #48

Earlier quoted context omitted.

I have no idea what you mean, there are obviously particles, we have an entire standard model full of them.

https://news.ycombinator.com/item?id=12377393 My understanding is that there is a growing consensus on this

As far as I can tell, I am admittedly not a physicist, this is at least a contentious issue and probably, again as far as I can tell, a popular misconception. Those fields in quantum field theory are mathematical tools, one starts with particles and then defines fields to mathematically handle system where particles are created and annihilated.

Think about it, think about all physics you have ever done, in school or wherever. You have probably never dealt with a situation where something was created or destroyed. You need variables to describe all the things you are dealing with, how do you add new variables or get rid of some old variables halfway in your calculation when something is created or destroyed?

This is what those fields in Fock space are for, they are mathematical tools to keep track of the number of particles you have in specific states. You do not start with a field and discover that it has quanta behaving like particles, you start with particles and just describe them with fields in order to be able to handle particle creation and annihilation.

Here is Nima Arkani-Hamed giving the Salam lectures 2012, a five day series on the state of fundamental physics. I marked [1] about 30 seconds where he is very clear about this. You can also start here [2] and watch about 10 minutes of this lecture where he quickly redevelops the ideas of quantum field theory.

Even if you can not follow all the details, you should easily be able to follow the explanation where the fields come from and why. The particles vs fields issue is explicitly discussed three or four times within those 10 minutes. You may of course want to watch the entire lecture series, it is really good and is pretty non-technical in the beginning. The last day I linked to is actually the exception if I remember correctly, the first four days are mostly without math.

[1] https://www.youtube.com/watch?v=tnA7bh7dTqY&t=1669

[2] https://www.youtube.com/watch?v=tnA7bh7dTqY&t=370

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

#55

Post by return0 »

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…

more like, someone puts both fruit in black bags, mixes them up and gives one to alice and one to charlie. alice does not know which one she got until bob eats his fruit or until charlie sees it.

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

#56

Post by return0 »

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…

They are not bound by speed of light. Nothing is exchanged or transmitted, the collapse of wavefunction is genuinely instant in both places. The drawback is that you cannot choose or predict which outcome you will measure, so you can't really use it to transmit information instantly.

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

#57

Post by M_Grey »

mirimir wrote: post #49
M_Grey wrote: post #47

Earlier quoted context omitted.

Fingers crossed At the very least, if QM emerges into your end of things, it should do so in clearly defined ways, and at scales/energies which have some hope of being probed.

I do love Stephenson's Anathem :)

Honestly, I love everything he writes... The Diamond Age in particular I think is a bit underrated.

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

#58

Post by eveningcoffee »

gdavisson wrote: post #35
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…

What you're describing is a local hidden variable theory. In this case, the "hidden variable" is who has which fruit. It's "local" because there's no remote influence -- Bob eating his fruit doesn't change which one Alice has. Bell's theorem places limits on the correlations that a theory like this can explain. Here's a simple example of a Bell violation: 1) Alice and Bob get together and conspire. They can do anythi…

What would happen if Alice and Bob somehow knew what questions will be asked?

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

#59

Post by [deleted] »

danbruc wrote: post #37
tedsanders wrote: post #29

Earlier quoted context omitted.

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...

One has to be careful what one means here. I meant it in the following specific sense and we have good experimental evidence for this. [...] there is no time, no matter how far the spins are separated, in which you could measure the second spin to have the same orientation as the one you just measured [...] If an interpretation makes use of non-locality to explain this fact is a different matter, but experimentally i…

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