Periodic Jacobi Operators with Complex Coefficients

Vassilis G. Papanicolaou

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arXiv · 1909.09206

Periodic Jacobi Operators with Complex Coefficients

Vassilis G. Papanicolaou

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Abstract

We present certain results on the direct and inverse spectral theory of the Jacobi operator with complex periodic coefficients. For instance, we show that any $N$-th degree polynomial whose leading coefficient is $(-1)^N$ is the Hill discriminant of finitely many discrete $N$-periodic Schr\"{o}dinger operators (Theorem 1). Also, in the case where the spectrum is a closed interval we prove a result (Theorem 5) which is the analog of Borg's Theorem for the non-self-adjoint Jacobi case.

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BibTeX RIS

Vassilis G. Papanicolaou. 2019-09-19. Periodic Jacobi Operators with Complex Coefficients. https://arxiv.org/abs/1909.09206

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