Perturbation of analytic hermitian matrix functions

Abstract

The behaviour of real eigenvalues of selfadjoint analytic matrix valued functions under small selfadjoint analytic perturbations is studied. Attention is paid mainly to the case when the perturbation is definite (or semidefi-nite). Earlier results of the authors concerning matrix polynomials of first degree are extended to the case of analytic functions.

AMS(MOS):

• 15A23

^*Research supported in part by the Natural Sciences and Engineering Research Council of Canada

^**Partly supported by the Fund for Basic Research Administrated by Israel Academy of Sciences and Humanities

^*Research supported in part by the Natural Sciences and Engineering Research Council of Canada

^**Partly supported by the Fund for Basic Research Administrated by Israel Academy of Sciences and Humanities

Notes

^*Research supported in part by the Natural Sciences and Engineering Research Council of Canada

^**Partly supported by the Fund for Basic Research Administrated by Israel Academy of Sciences and Humanities

Additional information

Notes on contributors

P. Lancaster

*

L. Rodman

**