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Determination of the domain of the admissible matrix elements in the four-dimensional PT-symmetric anharmonic model

Miloslav Znojil
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Abstract

Many manifestly non-Hermitian Hamiltonians (typically, PT-symmetric complex anharmonic oscillators) possess a strictly real, "physical" bound-state spectrum. This means that they are (quasi-)Hermitian with respect to a suitable non-standard metric. The domain D of the existence of this metric is studied here for a nontrivial though still non-numerical four-parametric "benchmark" matrix model.

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Miloslav Znojil. 2007-03-19. Determination of the domain of the admissible matrix elements in the four-dimensional PT-symmetric anharmonic model. https://doi.org/10.1016/j.physleta.2007.03.010

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