Is "entanglement" always entangled?

A. F. Kracklauer

Published 2001-08-13, updated 2001-11-21Version 2

Entanglement, including ``quantum entanglement,'' is a consequence of correlation between objects. When the objects are subunits of pairs which in turn are members of an ensemble described by a wave function, a correlation among the subunits induces the mysterious properties of ``cat-states.'' However, correlation between subsystems can be present from purely non-quantum sources, thereby entailing no unfathomable behavior. Such entanglement arises whenever the so-called ``qubit space'' is not afflicted with Heisenberg Uncertainty. It turns out that all optical experimental realizations of EPR's \emph{Gedanken} experiment in fact do not suffer Heisenberg Uncertainty. Examples will be analyzed and non-quantum models for some of these described. The consequences for experiments that were to test EPR's contention in the form of Bell's Theorem are drawn: \emph{valid tests of EPR's hypothesis have yet to be done.}