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arXiv · 1804.03425

Hermitian--to--quasi-Hermitian quantum phase transitions

Miloslav Znojil
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Abstract

The phenomenon of quantum phase transition is considered in the special case in which the evolution laws remain unitary and in which the bound-state energies remain observable. The conventional Hermiticity of observables is lost at the interface, replaced by the so called quasi-Hermiticity. Several features of the passage of the system through the interface are discussed and illustrated by elementary illustrative ${\cal PT}-$symmetric examples.

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Miloslav Znojil. 2018-04-10. Hermitian--to--quasi-Hermitian quantum phase transitions. https://doi.org/10.1103/physreva.97.042117

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