Andrew Clough wrote:
<I'd also like to note (since that section was cut out) that I was using
communication with the past to *disprove* quantum entanglement.>
>> snip <<
<This does not prove an absolute frame of reference!>
It is possible for a theory to be non-local
and Lorentz invariant at the same time?
When Bohm's non-local approach
is applied to relativistic quantum theory
we find that this theory is not Lorentz-invariant.
Bell's theorem (plus experiments) established
that (realistic) interpretations of QM must be non-local.
There's not, as far as I know, an analogous
*theorem* which proves that (realistic) interpretations
of QM must also be non-Lorentz-invariant.
Anyway an ideal experiment [1,2], by Lucien Hardy,
with 2 interferometers, one electron, one positron,
suggests that the simultaneous measurement
on these particles implies a preferred reference
frame (but does not tell us which frame is).
Another ideal device , by Ian Percival, consisting
in a double Bell-type experiment, with moving apparatuses
and linked outcomes, also suggests the existence of
a preferred refernce frame.
Now if there is a preferred reference frame, as implied
by these gedanken experiments, causal paradoxes
(such as backward causation, sending information
backward in time) are blocked.
The possible candidate for such a preferred reference
frame is the cosmic frame (as Bohm used to call it) and
especially the one in which the cosmic background
radiation is isotropic.
Notice that Wheeler  considered the possibility that
entanglement might occur on cosmological scales.
 Lucien Hardy, Phys. Rev. Lett., (1992), vol. 68, n. 20,
pages 2981 - 2984
 Hardy's "theorem" or "paradox" or "experiment" is also
discussed at http://arxiv.org/abs/quant-ph?0104062
 I.C. Percival, http://arxiv.org/abs/quant-ph?9811089
 J.A.Wheeler, Law without law, in "Quantum Theory
and Measurement", Wheeler and Zurek eds., Princeton
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