Re: Alternative approach to QM action at a distance

It's now occurred to me that perhaps the "spooky communication" needs
more than a scalar phase, if observations of two-state systems can vary
in more than one dimension.

For example, consider a Stern-Gerlach type experiment where a pair of
massive entangled spin-1/2 particles move apart relatively slowly and a
component of spin is observed in a direction which is not necessarily
perpendicular to the direction of motion. As far as I know, the
correlations between observations should still depend only on the angle
between the detector directions, regardless of the common plane that
they define. Is this right?

In this case, the only way for the correlations to be maintained via a
deterministic (non-local) mechanism is for the spatial direction of the
measurement at one end to be communicated non-locally to the other end
(but not the measurement result). This information cannot be
communicated by a single scalar phase value, but needs a direction in
space (which could in this case for example be communicated via
two-component spinor).

This could still be explained by some mechanism involving different
phase factors propagating at different speeds which combine to produce
a single-valued function, but it isn't quite as clear-cut as as a
scalar/spinor split.

Are there similar possible observations of two-state systems which can
be correlated in ways which require even more dimensions in the
communicated information?

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