On a family of differential operators with the coupling parameter in the boundary condition

G. Rozenblum; M. Solomyak

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On a family of differential operators with the coupling parameter in the boundary condition

G. Rozenblum·M. Solomyak

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Abstract

We study a family of differential operators $L_\alpha$ in two variables, depending on the coupling parameter $\alpha\ge0$ that appears only in the boundary conditions. Our main concern is the spectral properties of $L_\alpha$, which turn out to be quite different for $\alpha\le 1$ and for $\alpha>1$. In particular, $L_\alpha$ has a unique self-adjoint realization for $\alpha\le 1$ and many such realizations for $\alpha>1$. In the more difficult case $\alpha>1$ an analysis of non-elliptic pseudodifferential operators in dimension one is involved.

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BibTeX RIS

G. Rozenblum, M. Solomyak. 2005-10-18. On a family of differential operators with the coupling parameter in the boundary condition. https://arxiv.org/abs/math/0510371

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