
Was Einstein Wrong?: A Quantum Threat to Special Relativity - ksvs
http://www.sciam.com/article.cfm?id=was-einstein-wrong-about-relativity&print=true
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mark-t
I showed this article to a friend of mine who did a PhD in physics at
Cambridge. Here's what he had to say:

The entanglement arguments against relativity are fairly silly. From that
article, looks like Scientific American is going the way of the New Scientist.
:( Absolutely no mention of Everett and his MWI (editor's note: multiple
worlds interpretation) in the article I notice. Even though that's the most
obviously straightforward way of keeping special relativity, locality, quantum
mechanics and accounting for the Aspect experiment. Basically Bell's theorem
that is supposed to prove non-locality makes a subtle assumption called
"counter-factual definiteness", which implies among other things that
experiments have definite outcomes. Obviously it's violated by MWI. Really
it's only Bohmian mechanics that's non-local and arguably not consistent with
SR. Though Bohm adherents often claim that Copenhagen must be non-local by
Bell's theorem, they misunderstand the fact that the wavefunction in CI is
really an epistemic device and wavefunction collapse isn't thought to be a
genuine physical occurrence except by a very small minority. CI when viewed in
this way doesn't satisfy counter-factual definiteness either.

~~~
thisrod
Hear hear.

The article doesn't say what's new about the authors' ideas. You'd expect it
to mention the transactional interpretation of quantum mechanics - it isn't
news that the Aspect experiment can be explained if measurements affect things
that happened earlier.

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Anon84
Even if these conclusions are correct, they don't mean that "Einstein was
wrong".

Physical laws are approximate descriptions of reality that are based on
certain explicit or implicit assumptions and any conclusions that you derive
from them are valid only as long as they hold. If Einsteins assumptions are
proven to be invalid in certain regimes, it does not mean that the theory of
relativity is wrong, just incomplete (as we already knew it was).

For example:

Newton's laws are not wrong, they just assume that your velocity is much
smaller than the speed of light. If your velocity becomes close to light,
Newton's laws are no longer valid and you must use Einsteins relativity. On
the other hand, Relativity assumes that Quantum effects are negligible. If
your system is in the quantum regime, these assumption no longer hold and you
must use different laws.

~~~
tc
In the context of the article, it is pretty clear that the author isn't asking
whether Einstein was wrong per-se about special relativity; he is asserting
specifically that Einstein was partially mistaken in his criticism of quantum
mechanics and his dismissal of nonlocality (in the EPR paper). On the flip
side, he credits Einstein for seeing through the smoke-screen put up by Bohr
about separating physics from our conceptions of reality, that is, breaking
the link between physics and metaphysics.

------
tc
Summary:

For at least the last 70 years, physicists haven't taken the nonlocality
predicted by quantum mechanics seriously enough. Even supporters of QM
considered the prediction of nonlocality a liability, and tried to dismiss it
as an artifact in various ways. Since much of QM couldn't be experimentally
proven at the time, there was a fear that suggesting our assumptions of strict
locality of action to be false would lead everyone to dismiss QM out of hand.

So, when we were finally able to empirically prove most of QM's predictions in
the 80s, no one noticed that also meant nonlocality was a fact of our world,
and that we should probably take the time to square that with our assumptions
of spacetime geometry handed down by SR.

It now appears that to reconcile nonlocality with the things we know about
spacetime geometry, we're going to have to challenge at least one other long-
held assumption. One proposal suggests that not only is space nonlocal, but so
is time. Another hypothesis suggests that the state of our universe at any
given time is too infinitely complex to be reduced to even an infinite set of
truth propositions.

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jimfl
Obviously Einstein was wrong:
[http://www.planetary.org/programs/projects/innovative_techno...](http://www.planetary.org/programs/projects/innovative_technologies/pioneer_anomaly/)

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richardw
Or, you know, accept the transactional interpretation (which has a perfectly
good intuitive explanation) and get on with life.

