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arXiv · 1909.12545

Symplectic resolutions of character varieties

Gwyn Bellamy·Travis Schedler
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Abstract

In this article we consider the connected component of the identity of $G$-character varieties of compact Riemann surfaces of genus $g > 0$, for connected complex reductive groups $G$ of type $A$ (e.g., $SL_n$ and $GL_n$). We show that these varieties are symplectic singularities and classify which admit symplectic resolutions. The classification reduces to the semi-simple case, where we show that a resolution exists if and only if either $g=1$ and $G$ is a product of special linear groups of any rank and copies of the group $PGL_2$, or if $g=2$ and $G = (SL_2)^m$ for some $m$.

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BibTeXRIS

Gwyn Bellamy, Travis Schedler. 2019-09-27. Symplectic resolutions of character varieties. https://doi.org/10.2140/gt.2023.27.51

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