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arXiv · 0709.0483

The PT-symmetric brachistochrone problem, Lorentz boosts and non-unitary operator equivalence classes

Uwe Guenther·Boris F. Samsonov
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Abstract

The PT-symmetric (PTS) quantum brachistochrone problem is reanalyzed as quantum system consisting of a non-Hermitian PTS component and a purely Hermitian component simultaneously. Interpreting this specific setup as subsystem of a larger Hermitian system, we find non-unitary operator equivalence classes (conjugacy classes) as natural ingredient which contain at least one Dirac-Hermitian representative. With the help of a geometric analysis the compatibility of the vanishing passage time solution of a PTS brachistochrone with the Anandan-Aharonov lower bound for passage times of Hermitian brachistochrones is demonstrated.

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Uwe Guenther, Boris F. Samsonov. 2008-07-20. The PT-symmetric brachistochrone problem, Lorentz boosts and non-unitary operator equivalence classes. https://doi.org/10.1103/physreva.78.042115

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