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arXiv · 1409.2409

Representation Theorems for indefinite quadratic forms without spectral gap

Stephan Schmitz
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Abstract

The First and Second Representation Theorem for sign-indefinite quadratic forms are extended. We include new cases of unbounded forms associated with operators that do not necessarily have a spectral gap around zero. The kernel of the associated operators is determined for special cases. This extends results by Grubi\v{s}i\'c, Kostrykin, Makarov and Veseli\'c in [Mathematika 59 (2013), 169--189].

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Stephan Schmitz. 2014-09-08. Representation Theorems for indefinite quadratic forms without spectral gap. https://doi.org/10.1007/s00020-015-2252-3

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