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arXiv · 1504.00352

Cohomological Hall algebras and character varieties

Ben Davison
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Abstract

In this paper we investigate the relationship between twisted and untwisted character varieties via a specific instance of the Cohomological Hall algebra for moduli of objects in 3-Calabi-Yau categories introduced by Kontsevich and Soibelman. In terms of Donaldson--Thomas theory, this relationship is completely understood via the calculations of Hausel and Villegas of the E polynomials of twisted character varieties and untwisted character stacks. We present a conjectural lift of this relationship to the cohomological Hall algebra setting.

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Ben Davison. 2015-04-01. Cohomological Hall algebras and character varieties. https://arxiv.org/abs/1504.00352

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