A forbidden set for embedded eigenvalues

del Río Castillo, Rafael René

doi:10.1090/S0002-9939-1994-1191867-8

A forbidden set for embedded eigenvalues
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by Rafael René del Río Castillo PDF

Proc. Amer. Math. Soc. 121 (1994), 77-82 Request permission

Abstract:

We study the problem of embedding eigenvalues to the spectrum of a Sturm-Liouville operator in the half axis when this spectrum is a perfect set. We prove the existence of an uncountable dense subset of the spectrum for which, by modifying the condition at the left or by locally perturbing the potential, it is not possible to add any eigenvalues.

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