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arXiv · 2109.09000

Smaller Gershgorin disks for multiple eigenvalues for complex matrices

Imre Bárány·Jozsef Solymosi
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Abstract

Extending an earlier result for real matrices we show that multiple eigenvalues of a complex matrix lie in a reduced Gershgorin disk. One consequence is a slightly better estimate in the real case. Another one is a geometric application. Further results of a similar type are given for normal and almost symmetric matrices.

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Imre Bárány, Jozsef Solymosi. 2021-09-18. Smaller Gershgorin disks for multiple eigenvalues for complex matrices. https://arxiv.org/abs/2109.09000

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