The action of a Coxeter element on an affine root system

Reading, Nathan; Stella, Salvatore

doi:10.1090/proc/14769

The action of a Coxeter element on an affine root system
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by Nathan Reading and Salvatore Stella PDF

Proc. Amer. Math. Soc. 148 (2020), 2783-2798

Abstract:

The characterization of orbits of roots under the action of a Coxeter element is a fundamental tool in the study of finite root systems and their reflection groups. This paper develops the analogous tool in the affine setting, adding detail and uniformity to a result of Dlab and Ringel.

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