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arXiv · 2603.24816

Weak limit semigroup in operator theory and ergodic theory

Tanja Eisner·Valentin Gillet
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Abstract

We study the weak limit semigroup of an operator $T$, i.e., the set of all operators being weak limit points of the powers of $T$, in three different but related contexts: Koopman operators of measure-preserving transformations, contractions/isometries/unitaries on separable Hilbert spaces and positive operators on $L^p$-spaces. Hereby we focus on finding large subsets of the weak limit semigroup, in particular in the generic case.

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Tanja Eisner, Valentin Gillet. 2026-03-25. Weak limit semigroup in operator theory and ergodic theory. https://arxiv.org/abs/2603.24816

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