If so, would this “spooky action at a distance” still be spooky if that “distance” is actually shorter than it appears?
Sorry if this is a Noob question. Just trying to understand how Entangled Particles seem to communicate faster than light.
Edit: The reason for asking this is Wormholes seem to be the only way Entangled Particles can "communicate" their spin states faster than light could travel between them. I used the word "communicate" at the time of asking because I thought information was transmitted between the Entangled Particles. However, from what I understand now, information is not being transmitted FTL. Rather, Entangled Particles are correlated in a way which doesn't require transmission... Unless I misunderstood that part too.
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No. Wormholes do not play a role in entanglement. In fact, entangled particles don't 'communicate' in the usual sense; instead, they show nonlocal correlations which can sometimes exceed what you'd expect from, say, a pair of boxes containing socks of different colours. What Einstein got wrong wasn't the 'spooky', it was the 'action' - neither particle acts on the other upon measurement.
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First off, I want to point out that the word communication is a bit misleading. You cannot communicate information through quantum entanglement (No-communication theorem)
If you try to measure the properties (spin) of, say, an electron $$|\psi_{electron}\rangle = \alpha |\uparrow\rangle + \beta |\downarrow \rangle, $$ you have the probability of measuring spin up as $ \alpha^2$, while spin down is $\beta^2$. For an entangled state of two particles, the quantum state is such that $$|\psi\rangle = \alpha | \uparrow_1 \uparrow_2 \rangle + \beta |\downarrow_1 \downarrow_2 \rangle. $$ So if you measure spin up on the first particle, then the second particle is, by construction, also spin up. You essentially have no control over which spins you measure and therefore cannot use this for direct communication. Now the question is: how do the two particles know, maybe through a wormhole?
* A relatively new interpretation in AdS/CFT and entanglement entropy proposes that entanglement is indeed equivalent to a wormhole geometry* (Maldacena, Susskind : http://arxiv.org/abs/1306.0533). But be advised here, the claim, also known as ER = EPR (Einstein-Rosen aka the worm hole = Einstein-Podolsky-Rosen aka entanglement) is a conjecture using the holographic principle. It states that two entangled particles in quantum mechanics is holographically dual to a wormhole geometry. Which means that entanglement between particles in 3+1 dimensions can be interpreted as some wormhole geometry in 4+1 dimensions.
Whether or not this is the actual physical phenomenon is something I do not know.