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On Einstein Causality and Time Asymmetry in Quantum Physics

S. Wickramasekara·A. Bohm
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Abstract

A theorem of Hegerfeldt shows that if the spectrum of the Hamiltonian is bounded from below, then the propagation speed of certain probabilities does not have an upper bound. We prove a theorem analogous to Hegerfeldt's that appertains to asymmetric time evolutions given by a semigroup of operators. As an application, we consider a characterization of relativistic quasistable states by irreducible representations of the causal Poincare semigroup and study the implications of the new theorem for this special case.

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S. Wickramasekara, A. Bohm. 2003-02-07. On Einstein Causality and Time Asymmetry in Quantum Physics. https://doi.org/10.1088/0305-4470%2F35%2F47%2F105

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