Abstract
We compute the E-polynomials of the moduli spaces of representations of the fundamental group of a complex curve into \(\mathrm{\text{ SL} }(2,{\mathbb{C }}),\) for the case of small genus \(g,\) and allowing the holonomy around a fixed point to be any matrix of \(\mathrm{\text{ SL} }(2,{\mathbb{C }}),\) that is \(\,\text{ Id}\,, -\,\text{ Id}\,,\) diagonalisable, or of either of the two Jordan types. For this, we introduce a new geometric technique, based on stratifying the space of representations, and on the analysis of the behaviour of the E-polynomial under fibrations.



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Arapura, D.: The Leray spectral sequence is motivic. Invent. Math. 160, 567–589 (2005)
Boden, H., Yokogawa, K.: Moduli spaces of parabolic Higgs bundles and parabolic K(D) pairs over smooth curves: I. Int. J. Math. 7, 573–598 (1996)
de Cataldo, A., Hausel, T., Migliorini, L.: Topology of Hitchin systems and Hodge theory of character varieties: the case \(A_{1}\). Ann. Math. (2) 175(3), 1329–1407 (2012)
Corlette, K.: Flat \(G\)-bundles with cannonical metrics. J. Diff. Geom. 28, 361–382 (1988)
Deligne, P.: Équations différentielles á points singuliers réguliers. In: Lecture Notes in Mathematics, vol. 163. Springer, Berlin (1970)
Deligne, P.: Théorie de Hodge II. Publ. Math. I.H.E.S. 40, 5–5 (1971)
Deligne, P.: Théorie de Hodge III. Publ. Math. I.H.E.S. 44, 5–77 (1974)
Donaldson, S.: Twisted harmonic maps and the self duality equations. Proc. Lond. Math. Soc. 55, 127–131 (1987)
García-Prada, O., Gothen, P.B., Muñoz, V.: Betti numbers of the moduli space of rank 3 parabolic Higgs bundles. Mem. Am. Math. Soc. 187, viii+80 (2007)
García-Prada, O., Heinloth, J., Schmitt, A.: On the motives of moduli of chains and Higgs bundles, preprint, arXiv:1104.5558
Gothen, P.B.: The Betti numbers of the moduli space of rank 3 Higgs bundles. Int. J. Math. 5, 861–875 (1994)
Hausel, T.: Mirror symmetry and Langlands duality in the non-Abelian Hodge theory of a curve, Geometric methods in algebra and number theory, pp. 193–217. In: Progr. Math., vol. 235. Birkhauser, Basel (2005)
Hausel, T., Letellier, E., Rodriguez-Villegas, F.: Arithmetic harmonic analysis on character and quiver varieties. Duke Math. J. 160(2), 323–400 (2011)
Hausel, T.: Rodriguez Villegas, F.: Mixed Hodge polynomials of character varieties. Invent. Math. 174, 555–624 (2008)
Hausel, T., Thaddeus, M.: Mirror symmetry, Langlands duality and Hitchin systems. Invent. Math. 153, 197–229 (2003)
Hitchin, N.J.: The self-duality equations on a Riemann surface. Proc. Lond. Math. Soc. 55(3), 59–126 (1987)
Hitchin, N.J.: Stable bundles and integrable systems. Duke Math. J. 54, 91–114 (1987)
Mereb, M.: On the E-polynomials of a family of Character Varieties, Ph. D. dissertation, arXiv:1006.1286
Mehta, M.: Hodge structure on the cohomology of the moduli space of Higgs bundles, preprint, arXiv:math.AG/0112111
Muñoz, V., Ortega, D., Vázquez-Gallo, M.-J.: Hodge polynomials of the moduli space of pairs. Int. J. Math. 18, 695–721 (2007)
Muñoz, V., Ortega, D., Vázquez-Gallo, M.-J.: Hodge polynomials of the moduli space of triples of rank (2,2). Q. J. Math. 60, 235–272 (2009)
Muñoz, V.: The \(SL(2,{\mathbb{C}})\)-character varieties of torus knots. Rev. Mat. Complut. 22, 489–497 (2009)
Peters, C., Steenbrink, J.: Mixed Hodge Structures, vol. 52. Springer, Berlin (2007)
Simpson, C.: Constructing variations of Hodge structure using Yang-Mills theory and applications to uniformization. J. Am. Math. Soc. 1, 867–918 (1988)
Simpson, C.: Higgs bundles and local systems. Inst. Hautes Études Sci. Publ. Math. 75, 5–95 (1992)
Simpson, C.: Moduli space of representations of the fundamental group of a smooth projective variety II. Inst. Hautes Études Sci. Publ. Math. 80, 5–79 (1995)
Simpson, C.: Harmonic bundles on noncompact curves. J. Am. Math. Soc. 3, 713–770 (1990)
Acknowledgments
We thank Tamás Hausel and Richard Thomas for helpful comments. In particular, several conversations with T. Hausel have been invaluable to confirm the correctness of our polynomials. We also thank the referees for their careful reading of the paper.
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M. Logares is supported by an i-Math Future contract and partially supported by FCT (Portugal) through project PTDC/MAT/099275/2008 and (Spain) project MTM2010-17717. V. Muñoz is supported by (Spanish MICINN) research project MTM2010-17389. M. Logares and P. E. Newstead authors would like to thank the Isaac Newton Institute, where this work was completed during the Moduli Spaces programme.
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Logares, M., Muñoz, V. & Newstead, P.E. Hodge polynomials of SL\((2,\mathbb{C })\)-character varieties for curves of small genus. Rev Mat Complut 26, 635–703 (2013). https://doi.org/10.1007/s13163-013-0115-5
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DOI: https://doi.org/10.1007/s13163-013-0115-5

