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arXiv · 1410.1294

Some improvements of the Katznelson-Tzafriri theorem on Hilbert space

David Seifert
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Abstract

This paper extends two recent improvements in the Hilbert space setting of the well-known Katznelson-Tzafriri theorem by establishing both a version of the result valid for bounded representations of a large class of abelian semigroups and a quantified version for contractive representations. The paper concludes with an outline of an improved version of the Katznelson-Tzafriri theorem for individual orbits, whose validity extends even to certain unbounded representations.

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David Seifert. 2014-10-06. Some improvements of the Katznelson-Tzafriri theorem on Hilbert space. https://doi.org/10.1090/proc%2F12323

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