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Spectra of PT-Symmetric Operators and Perturbation Theory

Emanuela Caliceti·Sandro Graffi·Johannes Sjoestrand
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Abstract

Criteria are formulated both for the existence and for the non-existence of complex eigenvalues for a class of non self-adjoint operators in Hilbert space invarariant under a particular discrete symmetry. Applications to the PT-symmetric Schrödinger operators are discussed.

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Emanuela Caliceti, Sandro Graffi, Johannes Sjoestrand. 2004-07-22. Spectra of PT-Symmetric Operators and Perturbation Theory. https://doi.org/10.1088/0305-4470%2F38%2F1%2F013

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