Intrinsic reflections in Coxeter systems

Bernhard Mühlherr; Koji Nuida

doi:10.1016/j.jcta.2016.06.009

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arXiv · 1607.00757

Intrinsic reflections in Coxeter systems

Bernhard Mühlherr·Koji Nuida

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Abstract

Let $(W,S)$ be a Coxeter system and let $s \in S$. We call $s$ a right-angled generator of $(W,S)$ if $st = ts$ or $st$ has infinite order for each $t \in S$. We call $s$ an intrinsic reflection of $W$ if $s \in R^W$ for all Coxeter generating sets $R$ of $W$. We give necessary and sufficient conditions for a right-angled generator $s \in S$ of $(W,S)$ to be an intrinsic reflection of $W$.

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BibTeX RIS

Bernhard Mühlherr, Koji Nuida. 2016-07-04. Intrinsic reflections in Coxeter systems. https://doi.org/10.1016/j.jcta.2016.06.009

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