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arXiv · 2106.11108

Quasi-Hermitian one-dimensional lattice

Francisco M. Fernández
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Abstract

We show that a non-Hermitian operator with a tridiagonal matrix representation in a finite-dimensional vector space is similar to an Hermitian operator. The required condition is sufficient and simple examples show that it is not necessary. We derive quite general features of the eigenvalues and eigenvectors for a somewhat particular case.

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Francisco M. Fernández. 2021-08-16. Quasi-Hermitian one-dimensional lattice. https://arxiv.org/abs/2106.11108

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