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arXiv · 1502.02694

Non-Hermitian Hamiltonians and similarity transformations

Francisco M. Fernández
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Abstract

We show that similarity (or equivalent) transformations enable one to construct non-Hermitian operators with real spectrum. In this way we can also prove and generalize the results obtained by other authors by means of a gauge-like transformation and its generalization. Such similarity transformations also reveal the connection with pseudo-Hermiticity in a simple and straightforward way. In addition to it we consider the positive and negative eigenvalues of a three-parameter non-Hermitian oscillator.

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Francisco M. Fernández. 2015-02-04. Non-Hermitian Hamiltonians and similarity transformations. https://doi.org/10.1007/s10773-015-2724-x

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