Quasi-unitary equivalence and generalised norm resolvent convergence

Olaf Post; Jan Simmer

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arXiv · 2503.22611

Quasi-unitary equivalence and generalised norm resolvent convergence

Olaf Post·Jan Simmer

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Abstract

The purpose of this article is to give a short introduction to the concept of quasi-unitary equivalence of quadratic forms and its consequences. In particular, we improve an estimate concerning the transitivity of quasi-unitary equivalence for forms. We illustrate the abstract setting by two classes of examples.

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Olaf Post, Jan Simmer. 2025-03-28. Quasi-unitary equivalence and generalised norm resolvent convergence. https://arxiv.org/abs/2503.22611

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