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arXiv · 1402.6923

Arithmetic of character varieties of free groups

Sergey Mozgovoy·Markus Reineke
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Abstract

Via counting over finite fields, we derive explicit formulas for the E-polynomials and Euler characteristics of GL(d)- and PGL(d)-character varieties of free groups. We prove a positivity property for these polynomials and relate them to the number of subgroups of finite index.

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Sergey Mozgovoy, Markus Reineke. 2014-02-27. Arithmetic of character varieties of free groups. https://arxiv.org/abs/1402.6923

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