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arXiv · 1910.09421

Reflection groups and quiver mutation: Diagrammatics

Patrick Wegener
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Abstract

We extend Carter's notion of admissible diagrams and attach a "Dynkin-like" diagram to each reduced reflection factorization of an element in a finite Weyl group. We give a complete classification for the diagrams attached to reduced reflection factorizations. Remarkably, such a diagram turns out to be cyclically orientable if and only if it is isomorphic to the underlying graph of a quiver which is mutation-equivalent to a Dynkin quiver. Furthermore we show that each diagram encodes a natural presentation of the Weyl group as reflection group. The latter one extends work of Cameron, Seidel and Tsaranov as well as Barot and Marsh.

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Patrick Wegener. 2019-10-21. Reflection groups and quiver mutation: Diagrammatics. https://arxiv.org/abs/1910.09421

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