Journal of Mathematical Physics

Symmetries of history quantum theories and decoherence functionals

Oliver Rudolph

Published Nov 1, 1998• 3 citations

Abstract

Recently, Schreckenberg investigated symmetries in the context of history quantum theories. In the case that the space of histories is given by the set of projectors on some finite dimensional Hilbert space he obtained, first, a complete characterization of all physical symmetries of history quantum theories — an analog of Wigner’s theorem — and, second, a complete mathematical characterization of symmetries of single decoherence functionals. In this paper we extend Schreckenberg’s results to the case where the underlying space of histories is given by the set of projectors on some infinite dimensional Hilbert space.

DOI: 10.1063/1.532598

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