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E-polynomials of character varieties for real curves

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 نشر من قبل Thomas Baird
 تاريخ النشر 2020
  مجال البحث
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We calculate the E-polynomial for a class of the (complex) character varieties $mathcal{M}_n^{tau}$ associated to a genus $g$ Riemann surface $Sigma$ equipped with an orientation reversing involution $tau$. Our formula expresses the generating function $sum_{n=1}^{infty} E(mathcal{M}_n^{tau}) T^n$ as the plethystic logarithm of a product of sums indexed by Young diagrams. The proof uses point counting over finite fields, emulating Hausel and Rodriguez-Villegas.



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