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arXiv · 2505.09588

Basic representation theorems of forms

Zoltán Sebestyén·Zsigmond Tarcsay
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Abstract

We study maximal representations of nonnegative sesquilinear forms in real or complex Hilbert spaces, that are not necessarily closed or even closable. We associate positive self-adjoint operators with such forms, in a sense similar to Kato's representation theorems. In particular, we give a brief proof of the Friedrichs extension of a densely defined positive operator.

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Zoltán Sebestyén, Zsigmond Tarcsay. 2025-05-14. Basic representation theorems of forms. https://arxiv.org/abs/2505.09588

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