Re: Quantum entanglement and information transfer

From: Paul Stewart Snyder (ps_at_ws5.com)
Date: 07/19/04 

Date: 19 Jul 2004 04:09:09 -0400

tom129@juno.com (Tom Trotter) wrote in message news:<29df3039.0407152247.ba0eee4@posting.google.com>...
> ps@ws5.com (Paul Stewart Snyder) wrote in message news:<d16eb5af.0407141925.2054c9a0@posting.google.com>...
>
> [... snip]
>
> > We have A instantaneously changing state when
> > B does, no matter what the distance, and presumably
> > even if no measurement can be made. I see
> > shadows of the Copenhagen Interpretation, if we
> > moved toward a many worlds model would the idea
> > of instantaneous change be more likely to
> > have a physical reality?
>
> [ ... snip]
>
> The idea of instantaneous (simultaneous) change
> *does* have a physical reality (without MWI),
> doesn't it?
>
> Consider two photons emitted from
> the same atom and correlated in polarization.
> If you learn the polarization of one of the
> photons, then you instantly know the polarization
> of the other.
>
> Consider a wheel with two marks on opposite
> sides of it. As the wheel revolves, the
> opposing marks simultaneously change position.
>
> Consider two colliding objects whose momenta
> are known prior to their collision. In a
> sufficiently closed/isolated setting, subsequently
> learning the momentum of one of the objects
> will allow you to deduce the momentum of the
> other.
>
> The entities in the above examples have certain
> relationships to each other that allow their
> behavior to be correlated in some encompassing
> observational context. These correlations
> require no communication between the correlated
> entities.
>
> Or, am I missing your point?

It is true that if we know that A is opposite B, whenever we determine
A we know B, but that is not what I mean. In quantum entanglement when
A and B are entangled, if we determine A we know B – which is nothing
special – what really matters is that if we change the state of A we
instantaneously know that the state of B is changed. The argument is
that no information is transferred, which from an information theory
view is correct, yet I still feel that there is a communication of
some sort that we can recognize, a transfer that we are defining away
with classical models. We know that when A is changed B is
instantaneously changed, we know that we can cause an instantaneous
change in B, that should count for something when we consider the
information state of an observer at B (even if the only information is
that we know we caused the observer at B to observe something
different than he or she would otherwise have seen).

I agree when you say "The assumption that no signal can exceed the
speed of light?
According to the philosophers it is as fundamental and necessary as
indeterminism, and viceversa." However that does not mean that the
"deck is not stacked" with classical assumptions that require the
conclusions. As far as I can tell (and I may be very wrong) the
structure of arguments against a signal exceeding the speed of light
include assumptions that beg the question. Essentially relativity is
imposed on QM in such a way as to negate the argument that meaningful
FTL interactions are possible. The fact that quantum entanglement is
denied to be any kind of communication seems to be based on math and
logic that has built into it assumptions that FTL cannot exist?

PS

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