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The Gorenstein conjecture fails for the tautological ring of \(\mathcal{\overline{M}}_{2,n}\)

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We prove that for N equal to at least one of the integers 8, 12, 16, 20 the tautological ring \(R^{\bullet}(\overline {\mathcal {M}}_{2,N})\) is not Gorenstein. In fact, our N equals the smallest integer such that there is a non-tautological cohomology class of even degree on \(\overline {\mathcal {M}}_{2,N}\). By work of Graber and Pandharipande, such a class exists on \(\overline {\mathcal {M}}_{2,20}\), and we present some evidence indicating that N is in fact 20.

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References

  1. Behrend, K.A.: The Lefschetz trace formula for algebraic stacks. Invent. Math. 112(1), 127–149 (1993). doi:10.1007/BF01232427

    Article  MATH  MathSciNet  Google Scholar 

  2. Beĭlinson, A.A., Bernstein, J., Deligne, P.: Faisceaux pervers. In: Analysis and Topology on Singular Spaces, I, Luminy, 1981. Astérisque, vol. 100, pp. 5–171. Soc. Math. France, Paris (1982)

    Google Scholar 

  3. Bergström, J., Faber, C., van der Geer, G.: Siegel modular forms of genus 2 and level 2: cohomological computations and conjectures. Int. Math. Res. Not. 2008, 100 (2008)

    Google Scholar 

  4. Bergström, J., Faber, C., van der Geer, G.: Siegel modular forms of degree three and the cohomology of local systems. Preprint available at arXiv:1108.3731 (2011)

  5. Cavalieri, R., Yang, S.: Tautological pairings on moduli spaces of curves. Proc. Am. Math. Soc. 139(1), 51–62 (2011). doi:10.1090/S0002-9939-2010-10619-6

    Article  MATH  MathSciNet  Google Scholar 

  6. Deligne, P.: Théorie de Hodge. II. Publ. Math. IHÉS 40, 5–57 (1971)

    Article  MATH  MathSciNet  Google Scholar 

  7. Deligne, P.: Théorie de Hodge. III. Publ. Math. IHÉS 44, 5–77 (1974)

    Article  MATH  MathSciNet  Google Scholar 

  8. Deligne, P.: La conjecture de Weil. II. Publ. Math. IHÉS 52, 137–252 (1980). http://www.numdam.org/item?id=PMIHES_1980__52__137_0

    Article  MATH  MathSciNet  Google Scholar 

  9. Faber, C.: A conjectural description of the tautological ring of the moduli space of curves. In: Moduli of Curves and Abelian Varieties. Aspects Math., vol. E33, pp. 109–129. Vieweg, Braunschweig (1999)

    Chapter  Google Scholar 

  10. Faber, C.: Hodge integrals, tautological classes and Gromov-Witten theory. In: Proceedings of the Workshop Algebraic Geometry and Integrable Systems Related to String Theory, Kyoto, 2000, vol. 1232, pp. 78–87 (2001)

    Google Scholar 

  11. Faber, C.: Tautological algebras of moduli spaces of curves. In: Moduli Spaces of Riemann Surfaces. IAS/Park City Math. Ser. (to appear). Amer. Math. Soc., Providence. Preprint available at http://www.math.kth.se/~faber

  12. Faber, C., van der Geer, G.: Sur la cohomologie des systèmes locaux sur les espaces de modules des courbes de genre 2 et des surfaces abéliennes. I. C. R. Math. Acad. Sci. Paris 338(5), 381–384 (2004). doi:10.1016/j.crma.2003.12.026

    Article  MATH  MathSciNet  Google Scholar 

  13. Faber, C., van der Geer, G.: Sur la cohomologie des systèmes locaux sur les espaces de modules des courbes de genre 2 et des surfaces abéliennes. II. C. R. Math. Acad. Sci. Paris 338(6), 467–470 (2004). doi:10.1016/j.crma.2003.12.025

    Article  MATH  MathSciNet  Google Scholar 

  14. Faber, C., Pandharipande, R.: Logarithmic series and Hodge integrals in the tautological ring. Mich. Math. J. 48, 215–252 (2000). doi:10.1307/mmj/1030132716. With an appendix by Don Zagier, Dedicated to William Fulton on the occasion of his 60th birthday

    Article  MATH  MathSciNet  Google Scholar 

  15. Faber, C., Pandharipande, R.: Relative maps and tautological classes. J. Eur. Math. Soc. 7(1), 13–49 (2005). doi:10.4171/JEMS/20

    Article  MATH  MathSciNet  Google Scholar 

  16. Faber, C., Shadrin, S., Zvonkine, D.: Tautological relations and the r-spin Witten conjecture. Ann. Sci. Éc. Norm. Super. 43(4), 621–658 (2010)

    MATH  MathSciNet  Google Scholar 

  17. Faltings, G.: On the cohomology of locally symmetric Hermitian spaces. In: Paul Dubreil and Marie-Paule Malliavin Algebra Seminar, 35th Year, Paris, 1982. Lecture Notes in Math., vol. 1029, pp. 55–98. Springer, Berlin (1983). doi:10.1007/BFb0098927

    Google Scholar 

  18. Faltings, G., Chai, C.L.: Degeneration of Abelian Varieties. Ergebnisse der Mathematik und ihrer Grenzgebiete (3), vol. 22. Springer, Berlin (1990). With an appendix by David Mumford

    Book  MATH  Google Scholar 

  19. Farb, B., Margalit, D.: A Primer on Mapping Class Groups. Princeton Mathematical Series, vol. 49. Princeton University Press, Princeton (2012)

    Google Scholar 

  20. Fulton, W., Harris, J.: Representation Theory: A First Course. Graduate Texts in Mathematics, vol. 129. Springer, New York (1991). Readings in Mathematics

    MATH  Google Scholar 

  21. Fulton, W., MacPherson, R.: A compactification of configuration spaces. Ann. Math. 139(1), 183–225 (1994). doi:10.2307/2946631

    Article  MATH  MathSciNet  Google Scholar 

  22. Getzler, E.: Intersection theory on and elliptic Gromov-Witten invariants. J. Am. Math. Soc. 10(4), 973–998 (1997). doi:10.1090/S0894-0347-97-00246-4

    Article  MATH  MathSciNet  Google Scholar 

  23. Getzler, E.: The semi-classical approximation for modular operads. Commun. Math. Phys. 194(2), 481–492 (1998). doi:10.1007/s002200050365

    Article  MATH  MathSciNet  Google Scholar 

  24. Getzler, E.: Topological recursion relations in genus 2. In: Integrable Systems and Algebraic Geometry, Kobe/Kyoto, 1997, pp. 73–106. World Sci. Publ., River Edge (1998)

    Google Scholar 

  25. Getzler, E.: Resolving mixed Hodge modules on configuration spaces. Duke Math. J. 96(1), 175–203 (1999). doi:10.1215/S0012-7094-99-09605-9

    Article  MATH  MathSciNet  Google Scholar 

  26. Getzler, E.: Euler characteristics of local systems on \(\mathcal{M}_{2}\). Compos. Math. 132(2), 121–135 (2002). doi:10.1023/A:1015826400148

    Article  MATH  MathSciNet  Google Scholar 

  27. Graber, T., Pandharipande, R.: Constructions of nontautological classes on moduli spaces of curves. Mich. Math. J. 51(1), 93–109 (2003). doi:10.1307/mmj/1049832895

    Article  MATH  MathSciNet  Google Scholar 

  28. Graber, T., Vakil, R.: On the tautological ring of . Turk. J. Math. 25(1), 237–243 (2001)

    MATH  MathSciNet  Google Scholar 

  29. Graber, T., Vakil, R.: Relative virtual localization and vanishing of tautological classes on moduli spaces of curves. Duke Math. J. 130(1), 1–37 (2005). doi:10.1215/S0012-7094-05-13011-3

    Article  MATH  MathSciNet  Google Scholar 

  30. Green, M., Griffiths, P.: An interesting 0-cycle. Duke Math. J. 119(2), 261–313 (2003). doi:10.1215/S0012-7094-03-11923-7

    Article  MATH  MathSciNet  Google Scholar 

  31. Harder, G.: Eisenstein cohomology of arithmetic groups. The case \({\rm GL}\sb{2}\). Invent. Math. 89(1), 37–118 (1987). doi:10.1007/BF01404673

    Article  MATH  MathSciNet  Google Scholar 

  32. Harder, G.: Eisensteinkohomologie und die Konstruktion gemischter Motive. Lecture Notes in Mathematics, vol. 1562. Springer, Berlin (1993)

    MATH  Google Scholar 

  33. Harder, G.: The Eisenstein motive for the cohomology of \(\mathrm{GSp}_{2}(\mathbb{Z})\). In: Faber, C., Farkas, G., de Jong, R. (eds.) Geometry and Arithmetic. EMS Ser. Congr. Rep., pp. 143–164. Eur. Math. Soc., Zürich (2012). doi:10.4171/119-1/10

    Chapter  Google Scholar 

  34. Lee, Y.P.: Invariance of tautological equations. I. Conjectures and applications. J. Eur. Math. Soc. 10(2), 399–413 (2008). doi:10.4171/JEMS/115

    Article  MATH  MathSciNet  Google Scholar 

  35. Looijenga, E.: On the tautological ring of . Invent. Math. 121(2), 411–419 (1995). doi:10.1007/BF01884306

    Article  MATH  MathSciNet  Google Scholar 

  36. Mumford, D.: Towards an enumerative geometry of the moduli space of curves. In: Arithmetic and Geometry, vol. II. Progr. Math., vol. 36, pp. 271–328. Birkhäuser, Boston (1983)

    Chapter  Google Scholar 

  37. Pandharipande, R.: Three questions in Gromov-Witten theory. In: Proceedings of the International Congress of Mathematicians, vol. II, Beijing, 2002, pp. 503–512. Higher Ed. Press, Beijing (2002)

    Google Scholar 

  38. Pandharipande, R., Pixton, A.: Relations in the tautological ring. Preprint (2011). arXiv:1101.2236

  39. Petersen, D.: Cohomology of local systems on loci of d-elliptic abelian surfaces. Mich. Math. J. (to appear). Preprint (2010). arXiv:1004.5462

  40. Petersen, D.: The structure of the tautological ring in genus one. Preprint (2012). arXiv:1205.1586

  41. Raghunathan, M.S.: Cohomology of arithmetic subgroups of algebraic groups. I. Ann. Math. 86, 279–304 (1967)

    Article  Google Scholar 

  42. Randal-Williams, O.: Relations among tautological classes revisited. Adv. Math. 231(3–4), 1773–1785 (2012). doi:10.1016/j.aim.2012.07.017

    Article  MATH  MathSciNet  Google Scholar 

  43. Saper, L.: -modules and the conjecture of Rapoport and Goresky-MacPherson. Astérisque 298, 319–334 (2005). Automorphic forms. I

    MathSciNet  Google Scholar 

  44. Schwermer, J.: On Euler products and residual Eisenstein cohomology classes for Siegel modular varieties. Forum Math. 7(1), 1–28 (1995). doi:10.1515/form.1995.7.1

    Article  MATH  MathSciNet  Google Scholar 

  45. Stein, W.: The Modular Forms Database (2012). http://wstein.org/Tables

  46. Tavakol, M.: The tautological ring of the moduli space \(M_{1,n}^{ct}\). Preprint (2010). arXiv:1007.3091

  47. Tavakol, M.: The tautological ring of the moduli space \(M_{2,n}^{rt}\). Preprint (2011). arXiv:1101.5242

  48. Tommasi, O.: On the cohomology of local systems of low weight on \(\mathcal{M}_{2}\) (manuscript in preparation)

  49. Yin, Q.: On the tautological rings of M g,1 and its universal Jacobian. Preprint (2012). arXiv:1206.3783

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Correspondence to Dan Petersen.

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D.P. is supported by the Göran Gustafsson foundation for scientific and medical research. O.T. is supported by the Deutsche Forschungsgemeinschaft under grant Hu337/6-2.

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Petersen, D., Tommasi, O. The Gorenstein conjecture fails for the tautological ring of \(\mathcal{\overline{M}}_{2,n}\) . Invent. math. 196, 139–161 (2014). https://doi.org/10.1007/s00222-013-0466-z

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