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BOUNDED CONJUGACY CLASSES AND CONJUGACY CLASSES SUPPORTING INVARIANT MEASURES AND AUTOMORPHISMS

Published online by Cambridge University Press:  06 February 2025

C. R. E. RAJA*
Affiliation:
Stat-Math Unit, Indian Statistical Institute (ISI), 8th Mile Mysore Road, Bangalore 560 059, India

Abstract

We consider conjugacy classes in a locally compact group G that support finite G-invariant measures. If G is a property (M) extension of an abelian group, in particular, if G is a metabelian group, then any such conjugacy class is relatively compact. As an application, centralisers of lattices in such groups have bounded conjugacy classes. We use the same techniques to obtain results in the case of totally disconnected, locally compact groups.

Type
Research Article
Copyright
© The Author(s), 2025. Published by Cambridge University Press on behalf of Australian Mathematical Publishing Association Inc.

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Footnotes

The work was supported by SERC grant under MATRICS MTR/2022/000429.

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