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A decomposition theorem for locally compact groups

  • Sanjib Basu EMAIL logo und Krishnendu Dutta
Veröffentlicht/Copyright: 17. Oktober 2017
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Abstract

We prove that, under certain restrictions, every locally compact group equipped with a nonzero, σ-finite, regular left Haar measure can be decomposed into two small sets, one of which is small in the sense of measure and the other is small in the sense of category, and all such decompositions originate from a generalised notion of a Lebesgue point. Incidentally, such class of topological groups for which this happens turns out to be metrisable. We also observe an interesting connection between Luzin sets in such spaces and decompositions of the above type.

MSC 2010: 28Axx; 28C15

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Received: 2015-04-04
Accepted: 2015-06-29
Published Online: 2017-10-17
Published in Print: 2019-03-01

© 2019 Walter de Gruyter GmbH, Berlin/Boston

Heruntergeladen am 27.10.2025 von https://www.degruyterbrill.com/document/doi/10.1515/gmj-2017-0025/pdf?lang=de
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