@inbook{1d71b0e81360484da4eebf9357187a4f,
title = "Limit properties of eigenvalues in spectral gaps",
abstract = "Let S be a closed symmetric operator or relation with defect numbers (1, 1). The selfadjoint extensions A(τ) of S are parametrized over τ ∈ ℝ∪{∞}. When the selfadjoint extension A(0) has a spectral gap (α, β), then the same is true for all the other selfadjoint extensions A(τ) of S with the possible exception of an isolated eigenvalue λ(τ) of A(τ). The limiting properties of this isolated eigenvalue are studied in terms of τ.",
keywords = "Asymptotic expansion, Moment, Nevanlinna function, Selfadjoint extension, Spectral gap, Spectral measure, Symmetric operator",
author = "Seppo Hassi and {de Snoo}, Henk and Henrik Winkler",
year = "2018",
month = jan,
day = "1",
doi = "10.1007/978-3-319-68849-7_13",
language = "English",
isbn = "978-3-319-68848-0",
series = "Operator Theory: Advances and Applications",
publisher = "Springer",
pages = "335--355",
editor = "Daniel Alpay and Bernd Kirstein",
booktitle = "Indefinite Inner ProductSpaces, Schur Analysis,and Differential Equations",
}