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Boundary triples and Weyl functions for singular perturbations of self-adjoint operators

Andrea Posilicano
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Abstract

Given the symmetric operator $A_N$ obtained by restricting the self-adjoint operator $A$ to $N$, a linear dense set, closed with respect to the graph norm, we determine a convenient boundary triple for the adjoint $A_N^*$ and the corresponding Weyl function. These objects provide us with the self-adjoint extensions of $A_N$ and their resolvents.

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Andrea Posilicano. 2004-01-15. Boundary triples and Weyl functions for singular perturbations of self-adjoint operators. https://arxiv.org/abs/math/0309077

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