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Structured Pseudospectra for Small Perturbations

Profile image of michael karowmichael karow

2011, SIAM Journal on Matrix Analysis and Applications

https://doi.org/10.1137/090774744
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16 pages

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Abstract

In this paper we study the shape and growth of structured pseudospectra for small matrix perturbations of the form A A ∆ = A + B∆C, ∆ ∈ ∆, ∆ ≤ δ. It is shown that the properly scaled pseudospectra components converge to non-trivial limit sets as δ tends to 0. We discuss the relationship of these limit sets with µ-values and structured eigenvalue condition numbers for multiple eigenvalues.

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