Locally definite normal operators in Krein spaces

Friedrich Philipp

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arXiv · 1106.2579

Locally definite normal operators in Krein spaces

Friedrich Philipp

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Abstract

We introduce the spectral points of two-sided positive type of bounded normal operators in Krein spaces. It is shown that a normal operator has a local spectral function on sets which are of two-sided positive type. In addition, we prove that the Riesz-Dunford spectral subspace corresponding to a spectral set which is only of positive type is uniformly positive. The restriction of the operator to this subspace is then normal in a Hilbert space.

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Friedrich Philipp. 2011-07-29. Locally definite normal operators in Krein spaces. https://arxiv.org/abs/1106.2579

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