Essential pseudospectra and essential norms of band-dominated operators
نویسندگان
چکیده
منابع مشابه
Recycling Givens Rotations for the Efficient Approximation of Pseudospectra of Band–dominated Operators
We study spectra and pseudospectra of certain bounded linear operators on l(Z) . The operators are generally non-normal, and their matrix representation has a characteristic offdiagonal decay. Based on a result of Chandler-Wilde, Chonchaiya and Lindner for tridiagonal infinite matrices, we demonstrate an efficient algorithm for the computation of upper and lower bounds on the pseudospectrum of ...
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If a matrix or linear operator A is far from normal, its eigenvalues or, more generally, its spectrum may have little to do with its behavior as measured by quantities such as ‖An‖ or ‖exp(tA)‖. More may be learned by examining the sets in the complex plane known as the pseudospectra of A, defined by level curves of the norm of the resolvent, ‖(zI − A)−1‖. Five years ago, the author published a...
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ژورنال
عنوان ژورنال: Journal of Mathematical Analysis and Applications
سال: 2016
ISSN: 0022-247X
DOI: 10.1016/j.jmaa.2015.11.060