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arXiv · 2105.07417

Canonical reduced expression for elements of affine Coxeter groups Part I -- Type $\tilde{A}_n$

Sadek Al Harbat
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Abstract

We classify the elements of $W(\tilde{A}_n)$ by giving a canonical reduced expression for each, using basic tools among which affine length. We give some direct consequences for such a canonical form: a description of left multiplication by a simple reflection, a study of the right descent set, and a proof that the affine length is preserved along the tower of affine Coxeter groups of type $\tilde A$, which implies in particular that the corresponding tower of affine Hecke algebras is a faithful tower.

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BibTeXRIS

Sadek Al Harbat. 2021-05-16. Canonical reduced expression for elements of affine Coxeter groups Part I -- Type $\tilde{A}_n$. https://arxiv.org/abs/2105.07417

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