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On indecomposable normal matrices in spaces with indefinite scalar product

Olga Holtz
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Abstract

Finite dimensional linear spaces (both complex and real) with indefinite scalar product [.,.] are considered. Upper and lower bounds are given for the size of an indecomposable matrix that is normal with respect to this scalar product in terms of specific functions of v = min{v-, v+}, where v-, (v+) is the number of negative (positive) squares of the form [x,x]. All the bounds except for one are proved to be strict.

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Olga Holtz. 2005-12-27. On indecomposable normal matrices in spaces with indefinite scalar product. https://doi.org/10.1016/s0024-3795(96)00247-9

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