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arXiv · 2512.15467

On regularity of compressions and diagonals of operator functions

Vladimir Müller·Yuri Tomilov
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Abstract

Replacing operators with continuous operator-valued functions, we prove time-dependent versions of well-known results on compressions and diagonals of bounded operators. The setting of smooth functions is also addressed. Our results have no analogues in the literature and rely on a new technique. The results are especially transparent for selfadjoint operators.

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Vladimir Müller, Yuri Tomilov. 2025-12-17. On regularity of compressions and diagonals of operator functions. https://arxiv.org/abs/2512.15467

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