Spectral enclosures for a class of block operator matrices
نویسندگان
چکیده
منابع مشابه
Spectral properties of unbounded JJ-self-adjoint block operator matrices
We study the spectrum of unbounded J-self-adjoint block operator matrices. In particular, we prove enclosures for the spectrum, provide a sufficient condition for the spectrum being real and derive variational principles for certain real eigenvalues even in the presence of non-real spectrum. The latter lead to lower and upper bounds and asymptotic estimates for eigenvalues. AMS Subject classifi...
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ژورنال
عنوان ژورنال: Journal of Functional Analysis
سال: 2020
ISSN: 0022-1236
DOI: 10.1016/j.jfa.2019.108455