Interplay of pseudo-Hermitian symmetries and degenerate manifolds in the eigenspectrum of non-Hermitian systems

Grigory A. Starkov

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arXiv · 2402.07690

Interplay of pseudo-Hermitian symmetries and degenerate manifolds in the eigenspectrum of non-Hermitian systems

Grigory A. Starkov

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Abstract

In this letter, we study how the spectrum of pseudo-Hermitian systems is influenced by the ambiguity in the choice of the pseudo-metric operator. In particular, we analyze the case when different parameter-independent choices of pseudo-metric are possible and how it can lead to the appearance of robust degenerate manifolds in the parameter space of the system.

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Grigory A. Starkov. 2024-02-12. Interplay of pseudo-Hermitian symmetries and degenerate manifolds in the eigenspectrum of non-Hermitian systems. https://arxiv.org/abs/2402.07690

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