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arXiv · 1003.1908

Representation Theorems for Indefinite Quadratic Forms Revisited

Luka Grubisic·Vadim Kostrykin·Konstantin A. Makarov·Kresimir Veselic
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Abstract

The first and second representation theorems for sign-indefinite, not necessarily semi-bounded quadratic forms are revisited. New straightforward proofs of these theorems are given. A number of necessary and sufficient conditions ensuring the second representation theorem to hold is proved. A new simple and explicit example of a self-adjoint operator for which the second representation theorem does not hold is also provided.

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BibTeXRIS

Luka Grubisic, Vadim Kostrykin, Konstantin A. Makarov, Kresimir Veselic. 2012-04-10. Representation Theorems for Indefinite Quadratic Forms Revisited. https://doi.org/10.1112/s0025579312000125

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