Factorization theorem for the transfer function of a 2x2 operator matrix with unbounded couplings

V. Hardt; R. Mennicken; A. K. Motovilov

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Factorization theorem for the transfer function of a 2x2 operator matrix with unbounded couplings

V. Hardt·R. Mennicken·A. K. Motovilov

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Abstract

We consider the analytic continuation of the transfer function associated with a 2x2 operator matrix having unbounded couplings into unphysical sheets of its Riemann surface. We construct a family of non-selfadjoint operators which factorize the transfer function and reproduce certain parts of its spectrum including the nonreal (resonance) spectrum situated in the unphysical sheets neighboring the physical sheet.

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BibTeX RIS

V. Hardt, R. Mennicken, A. K. Motovilov. 1999-12-29. Factorization theorem for the transfer function of a 2x2 operator matrix with unbounded couplings. https://arxiv.org/abs/math/9912220

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