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ON THE CONNECTEDNESS OF THE CHABAUTY SPACE OF A LOCALLY COMPACT PRONILPOTENT GROUP

Published online by Cambridge University Press:  17 May 2021

BILEL KADRI*
Affiliation:
Sfax Preparatory Engineering Institute, Department of Mathematics, Sfax University, 3018 Sfax, Tunisia

Abstract

Let G be a locally compact group and let ${\mathcal {SUB}(G)}$ be the hyperspace of closed subgroups of G endowed with the Chabauty topology. The main purpose of this paper is to characterise the connectedness of the Chabauty space ${\mathcal {SUB}(G)}$ . More precisely, we show that if G is a connected pronilpotent group, then ${\mathcal {SUB}(G)}$ is connected if and only if G contains a closed subgroup topologically isomorphic to ${{\mathbb R}}$ .

Type
Research Article
Copyright
© 2021 Australian Mathematical Publishing Association Inc.

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