Skip to main content
Log in

Tropicalizing the moduli space of spin curves

  • Published:
Selecta Mathematica Aims and scope Submit manuscript

Abstract

We study the tropicalization of the moduli space of algebraic spin curves, \(\overline{\mathcal {S}}_{g,n}\). We exhibit its combinatorial stratification and prove that the strata are irreducible. We construct the moduli space of tropical spin curves \(\overline{S}_{g,n}^{{\text {trop}}}\), prove that is naturally isomorphic to the skeleton of the analytification, \(\overline{S}_{g,n}^{{\text {an}}}\), of \(\overline{\mathcal {S}}_{g,n}\), and give a geometric interpretation of the retraction of \(\overline{S}_{g,n}^{{\text {an}}}\) onto its skeleton in terms of a tropicalization map \(\overline{S}_{g,n}^{{\text {an}}}\rightarrow \overline{S}_{g,n}^{{\text {trop}}}\).

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4

Similar content being viewed by others

References

  1. Abramovich, D., Jarvis, T.: Moduli of twisted spin curves. Proc. Am. Math. Soc. 131, 685–699 (2003)

    Article  MathSciNet  Google Scholar 

  2. Abramovich, D., Caporaso, L., Payne, S.: The tropicalization of the moduli space of curves. Ann. Sci. Éc. Norm. Supér. 48(4), 765–809 (2015)

    Article  MathSciNet  Google Scholar 

  3. Abreu, A., Pacini, M.: The universal tropical Jacobian and the skeleton of the Esteves’ universal Jacobian. Proceedings of the London Mathematical Society. Preprint arXiv:1806.05527(to appear)

  4. Arbarello, E., Cornalba, M., Griffiths, P.: Geometry of Algebraic Curves. Volume II. Grundlehren der Mathematischen Wissenschaften, vol. 268. Springer, Heidelberg (2011)

    MATH  Google Scholar 

  5. Baker, M., Len, Y., Morrison, R., Pflueger, N., Ren, Q.: Bitangents of tropical plane quartic curves. Math. Zeit. 282(3), 1017–1031 (2016)

    Article  MathSciNet  Google Scholar 

  6. Bini, G., Fontanari, C.: Moduli of curves and spin structures via algebraic geometry. Trans. Am. Math. Soc. 358, 3207–3217 (2006)

    Article  MathSciNet  Google Scholar 

  7. Berkovich, V.: Spectral Theory and Analytic Geometry Over Non-Archimedean Fields. Mathematical Surveys and Monographs, vol. 33. AMS, Providence (1990)

    MATH  Google Scholar 

  8. Brannetti, S., Melo, M., Viviani, F.: On the tropical Torelli map. Adv. Math. 3, 2546–2586 (2011)

    Article  MathSciNet  Google Scholar 

  9. Caporaso, L.: Geometry of the theta divisor of a compactified Jacobian. J. Eur. Math. Soc. 11(6), 1385–1427 (2009)

    Article  MathSciNet  Google Scholar 

  10. Caporaso, L., Casagrande, C.: Combinatorial properties of stable spin curves. Commun. Algebra 31(8), 3653–3672 (2003)

    Article  MathSciNet  Google Scholar 

  11. Caporaso, L., Casagrande, C., Cornalba, M.: Moduli of roots of line bundles on curves. Trans. Am. Math. Soc. 359, 3733–3768 (2007)

    Article  MathSciNet  Google Scholar 

  12. Caporaso, L., Christ, K.: Combinatorics of universal compactified Jacobians. Adv. Math. (2019). https://doi.org/10.1016/j.aim.2019.02.019. Preprint arXiv:1801.04098

    Article  MATH  Google Scholar 

  13. Cavalieri, R., Markwig, H., Ranganathan, D.: Tropicalizing the space of admissible covers. Math. Ann. 364(3–4), 1275–1313 (2016)

    Article  MathSciNet  Google Scholar 

  14. Chan, M., Jiradilok, P.: Theta characteristics of tropical K4-curves. In: Combinatorial Algebraic Geometry, pp. 65–86. Fields Inst. Commun., 80. The Fields Institute for Research in Mathematical Sciences, Toronto (2017)

  15. Chiodo, A.: Towards an enumerative geometry of the moduli space of twisted curves and rth roots. Comput. Math. 144, 1461–1496 (2008)

    MATH  Google Scholar 

  16. Cornalba, M.: Moduli of curves and theta-characteristics. In: Lectures on Riemann Surfaces: Proceedings of the College on Riemann Surfaces, I.C.T.P., Trieste, 1987, World Scientific, 560–589 (1989)

  17. Deligne, P., Mumford, D.: The irreducibility of the space of curves of given genus. Publ. Math. IHES 36, 75–110 (1969)

    Article  MathSciNet  Google Scholar 

  18. Diestel, R.: Graph theory. Grundlehren der Mathematischen Wissenschaften, vol. 173. Springer, Berlin (1997)

  19. Farkas, G.: The birational type of the moduli space of even spin curves. Adv. Math. 1223(2), 433–443 (2010)

    Article  MathSciNet  Google Scholar 

  20. Farkas, G., Verra, A.: The geometry of the moduli space of odd spin curves. Ann. Math. 180(3), 927–970 (2014)

    Article  MathSciNet  Google Scholar 

  21. Harris, J.: Theta-characteristics on algebraic curves. Trans. Am. Math. Soc. 271(2), 611–638 (1982)

    Article  MathSciNet  Google Scholar 

  22. Jarvis, T.: Torsion-free sheaves and moduli of generalized spin curves. Comput. Math. 110, 291–333 (1998)

    MathSciNet  MATH  Google Scholar 

  23. Jarvis, T.: Geometry of the moduli of higher spin curves. Int. J. Math. 11(5), 637–663 (2000)

    Article  MathSciNet  Google Scholar 

  24. Jarvis, T., Kimura, T., Vaintrob, A.: Moduli spaces of higher spin curves and integrable hierarchies. Comput. Math. 126, 157–212 (2001)

    MathSciNet  MATH  Google Scholar 

  25. Jensen, D., Len, Y.: Tropicalization of theta characteristics, double covers, and Prym varieties. Sel. Math. (N.S.) 24(2), 1391–1410 (2018)

    Article  MathSciNet  Google Scholar 

  26. Len, Y., Markwig, H.: Lifting tropical bitangents. J. Symb. Comput. 96, 122–152 (2020)

    Article  MathSciNet  Google Scholar 

  27. Panizzut, M.: Theta characteristics of hyperelliptic graphs. Arch. Math. (Basel) 106(5), 445–455 (2016)

    Article  MathSciNet  Google Scholar 

  28. Ulirsch, M.: Tropical geometry of moduli spaces of weighted stable curves. J. Lond. Math. Soc. 92, 427–450 (2015)

    Article  MathSciNet  Google Scholar 

  29. Viviani, F.: Tropicalizing vs compactifying the Torelli morphism. In: Tropical and Non-Archimedean Geometry. Contemp. Math. 605, 181–210 (2013)

  30. Zharkov, I.: Tropical theta characteristics. In: Mirror Symmetry and Tropical Geometry. Contemp. Math. 527, 165–168. AMS, Providence (2010)

Download references

Acknowledgements

We thank Alex Abreu, Eduardo Esteves, Martin Ulirsch, and Filippo Viviani for several useful remarks. Part of the material in this paper is based upon work supported by the National Science Foundation under Grant No. DMS-1440140 while the first named author was visiting the Mathematical Sciences Research Institute in Berkeley, California.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Margarida Melo.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Caporaso, L., Melo, M. & Pacini, M. Tropicalizing the moduli space of spin curves. Sel. Math. New Ser. 26, 16 (2020). https://doi.org/10.1007/s00029-020-0539-y

Download citation

  • Published:

  • DOI: https://doi.org/10.1007/s00029-020-0539-y

Keywords

Mathematics Subject Classification

Navigation