Ok here is my response (you may post it):
I am not sure that SH really understands what statistical
independence means (although other people have already tried to explain
it to her).
To quote S. Goldstein, T. Norsen, D.V. Tausk and N. Zangh\`{\i}:
Bell's theorem, {\it Scholarpedia} 6(10): 8378 (2011) (which is quoted in my book Making sense of QM):
``if you are performing a drug versus placebo clinical trial, then
you have to select some group of patients to get the drug and some group
of patients to get the placebo." But for that to work, you have to
assume ``that the method of selection
is independent of whatever characteristics those patients might have
that might influence how they react to the drug". If, by accident, the
people to whom the placebo is given were exactly those that are cured
spontaneously, while those to whom the drug is
given are so sick that the drug has little effect on them, then of
course the study would be biased. And no matter how ``random" the chosen
sample is, this will always remain a logical possibility.
This is an example of what is called statistical independence. But the same sort of assumptions is used throughout science.
Turning to the EPR-Bell experiment, statistical independence means
that the properties of the incoming particles (electrons or photons) are
independent of the direction in which their spin or polarization will
be « measured »; but since the latter
can be chosen in an arbitrary way (by random number generators, by the
digits of pi, by the letters in the Bible or the analects or by the
evenness of the number of stars in a portion of the sky) even when the
particles are in flight, denying , statistical
independence means that one assumes incredible correlations between
the properties of the incoming particles and not only the method used
to choose the direction in which the spin or polarization will be
« measured », but also with the properties of the
random number generators, of the digits of pi, of the letters in the
Bible or the analects, of the evenness of the number of stars in a
portion of the sky or of any other system used to make that choice.
This is the same problem as the one with the placebo mentioned above, only much much bigger.
Some people think that what SH assumes is just universal
determinism, à la Laplace. But no! She is assuming very subtle
correlations whose existence does not follow from mere determinism. For
example, one can say that there is no correlation between
the amount of rice produced in China and the number of car accidents in
France, in a given time period, even though both are determined (in a
deterministic universe) by the initial conditions of the universe and
one can multiply such examples ad infinitum.
In fact, if one accepts the correlations that SH assumes, one can
« save » any superstition one wants. Take astrology: most of its
predictions are never checked, but when they are (taken at random) they
usually fail. But one might argue, à la
SH, that there is a subtle correlation between the fact of checking an
astrological prediction and its veracity, so that all astrological
predictions are true except the ones one checks.
In the end, SH assumption is no different from the Duhem-Quine
thesis in philosophy of science: any theory can be held true if one is
willing to make sufficiently ad hoc assumptions in one’s system.
So there is nothing new here and Bell’s inequality and its
verification do prove the existence of actions at a distance, at least
according to normal scientific reasoning.
Best,
Jean
| 8:14 AM (20 minutes ago) | ||
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