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ABSOLUTE ORDER AND INVOLUTIONS

Published online by Cambridge University Press:  23 October 2025

THOMAS GOBET*
Affiliation:
Université Clermont Auvergne , LMBP, UMR 6620 (CNRS), Campus des Cézeaux, 3 place Vasarely, TSA 60026, CS 60026, 63178 Aubière cedex, France

Abstract

We study the restriction of the absolute order on a Coxeter group W to an interval $[1,w]_T$, where $w\in W$ is an involution. We characterise and classify those involutions w for which $[1,w]_T$ is a lattice, using the notion of involutive parabolic subgroups.

MSC classification

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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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