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arXiv · gr-qc/9409003

Nonlinearity in Quantum Theory and Closed Timelike Curves

M. J. Cassidy
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Abstract

We examine consequences of the density matrix approach to quantum theory in the context of a model spacetime containing closed timelike curves and find that in general, an initially pure state will evolve in a nonlinear way to a mixed quantum state. CPT invariance and the implications of this nonlinearity for the statistical interpretation of quantum theory are discussed.

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M. J. Cassidy. 1994-09-03. Nonlinearity in Quantum Theory and Closed Timelike Curves. https://doi.org/10.1103/physrevd.52.5676

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