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arXiv · 1403.1464

On the description of subsystems in relativistic hypersurface Bohmian mechanics

Detlef Dürr·Matthias Lienert
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Abstract

A candidate for a realistic relativistic quantum theory is the hypersurface Bohm-Dirac model. Its formulation uses a foliation of spacetime into space-like hypersurfaces. This structure may well arise from the universal wave function itself, entailing the relativistic character of the theory despite the appearance of a preferred foliation. However, to apply the theory and to make contact with the usual quantum formalism one needs a framework for the description of subsystems. The presence of spin together with the foliation renders the subsystem description more complicated as compared to the non-relativistic case with spin. In this paper, we provide such a framework in terms of an appropriate conditional density matrix and an effective wave function as well as clarify their relation, thereby generalizing previous subsystem descriptions in the non-relativistic case.

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Detlef Dürr, Matthias Lienert. 2014-09-10. On the description of subsystems in relativistic hypersurface Bohmian mechanics. https://doi.org/10.1098/rspa.2014.0181

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