Thursday, May 19, 2011

Nonrelativistic entanglement

A Scientific American Magazine (March 2009) starts:
Was Einstein Wrong?: A Quantum Threat to Special Relativity

Entanglement, like many quantum effects, violates some of our deepest intuitions about the world. It may also undermine Einstein's special theory of relativity

Our intuition, going back forever, is that to move, say, a rock, one has to touch that rock, or touch a stick that touches the rock, or give an order that travels via vibrations through the air to the ear of a man with a stick that can then push the rock—or some such sequence. This intuition, more generally, is that things can only directly affect other things that are right next to them. If A affects B without being right next to it, then the effect in question must be indirect—the effect in question must be something that gets transmitted by means of a chain of events in which each event brings about the next one directly, in a manner that smoothly spans the distance from A to B. Every time we think we can come up with an exception to this intuition—say, flipping a switch that turns on city street lights (but then we realize that this happens through wires) or listening to a BBC radio broadcast (but then we realize that radio waves propagate through the air)—it turns out that we have not, in fact, thought of an exception. Not, that is, in our everyday experience of the world.

We term this intuition "locality."

Quantum mechanics has upended many an intuition, but none deeper than this one. And this particular upending carries with it a threat, as yet unresolved, to special relativity -— a foundation stone of our 21st-century physics.”
It is behind a paywall, but more of it can be found here and here.

After a bunch of goofy theorizing, it concludes:
The status of Special Relativity (just more than a century after it was presented to the World) is suddenly a radically open and rapidly developing question. This situation has come about because physicists and philosophers have finally followed through on the loose ends of Einstein's long- neglected argument with Quantum Mechanics -- an irony-laden further proof of Einstein's genius.

The diminished guru may very well have been wrong just where we thought he was "right" and right just where we thought he was "wrong". We may, in fact, see the Universe through a glass not quite so darkly as has too long been insisted.
This is nonsense. There is no problem combining quantum mechanics with special relativity. Einstein and quantum mechanics drive people to say the craziest things.

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