Skip to main content

Abstract

We study the conductor of Picard curves over \(\mathbb {Q}\), which is a product of local factors. Our results are based on previous results on stable reduction of superelliptic curves that allow one to compute the conductor exponent f p at the primes p of bad reduction. A careful analysis of the possibilities of the stable reduction at p yields restrictions on the conductor exponent f p . We prove that Picard curves over \(\mathbb {Q}\) always have bad reduction at p = 3, with f 3 ≥ 4. As an application we discuss the question of finding Picard curves with small conductor.

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

Access this chapter

Chapter
USD 29.95
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
eBook
USD 89.00
Price excludes VAT (USA)
  • Available as EPUB and PDF
  • Read on any device
  • Instant download
  • Own it forever
Softcover Book
USD 119.99
Price excludes VAT (USA)
  • Compact, lightweight edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info
Hardcover Book
USD 169.99
Price excludes VAT (USA)
  • Durable hardcover edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info

Tax calculation will be finalised at checkout

Purchases are for personal use only

Institutional subscriptions

Notes

  1. 1.

    By k-linear action we mean that the action is compatible with the structure of \(\bar {Y}\) as a k-scheme.

  2. 2.

    When working in a local context, \(f_{\mathfrak {p}}\) is often simply called the conductor of Y .

  3. 3.

    The precise meaning of an effective proof is that it provides an explicitly computable bound on the height of the curve or abelian variety in question.

References

  1. M. Börner, L-functions of curves of genus ≥ 3. Ph.D. thesis, Universität Ulm, 2016, http://dx.doi.org/10.18725/OPARU-4137

  2. I.I. Bouw, S. Wewers, Semistable reduction of curves and computation of bad Euler factors of L-functions. Notes for a minicourse at ICERM (2015), https://www.uni-ulm.de/fileadmin/website_uni_ulm/mawi.inst.100/mitarbeiter/wewers/course_notes.pdf

  3. I.I. Bouw, S. Wewers, Computing L-functions and semistable reduction of superelliptic curves. Glasg. Math. J. 59, 77–108 (2017)

    Article  MathSciNet  Google Scholar 

  4. A. Brumer, K. Kramer, The conductor of an abelian variety. Compos. Math. 92(2), 227–248 (1994)

    MathSciNet  MATH  Google Scholar 

  5. P. Deligne, D. Mumford, The irreducibility of the space of curves of given genus. Publ. Math. IHES 36, 75–109 (1969)

    Article  MathSciNet  Google Scholar 

  6. G. Faltings, Endlichkeitssätze für abelsche Varietäten über Zahlkörpern. Invent. Math. 73, 349–366 (1983)

    Article  MathSciNet  Google Scholar 

  7. J. Harris, D. Mumford, On the Kodaira dimension of the moduli space of curves. Invent. Math. 67, 23–86 (1982)

    Article  MathSciNet  Google Scholar 

  8. R.P. Holzapfel, The Ball and Some Hilbert Problems (Birkhäuser, Basel, 1995)

    Book  Google Scholar 

  9. K. Koike, A. Weng, Construction of CM Picard curves. Math. Comput. 74(249), 499–518 (2005)

    Article  MathSciNet  Google Scholar 

  10. Q. Liu, Conducteur et discriminant minimal de courbes de genre 2. Compos. Math. 94(1), 51–79 (1994)

    MathSciNet  MATH  Google Scholar 

  11. Q. Liu, Algebraic Geometry and Arithmetic Curves (Oxford University Press, Oxford, 2006)

    MATH  Google Scholar 

  12. B. Malmskog, C. Rasmussen, Picard curves over Q with good reduction away from 3. LMS Comput. (2016). arXiv:1407.7892

    Google Scholar 

  13. E. Picard, Sur des fonctions de deux variables indépendantes analogues aux fonctions modulaires. Acta Math. 2(1), 114–135 (1883)

    Article  MathSciNet  Google Scholar 

  14. R. Pries, Wildly ramified covers with large genus. J. Number Theory 119(2), 194–209 (2006)

    Article  MathSciNet  Google Scholar 

  15. J.R. Quine, Jacobian of the Picard curve, in Extremal Riemann Surfaces (San Francisco, CA, 1995). Contemporary Mathematics, vol. 201 (American Mathematical Society, Providence, RI, 1997), pp. 33–41

    Google Scholar 

  16. M. Raynaud, Spécialisation des revêtements en caractéristique p > 0. Ann. Sci. Éc. Norm. Supér. 32(1), 87–126 (1999)

    Article  MathSciNet  Google Scholar 

  17. J. Rüth, Models of curves and valuations. Ph.D. thesis, Universität Ulm, 2014, http://dx.doi.org/10.18725/OPARU-3275

  18. J. Rüth, S. Wewers, Semistable reduction of superelliptic curves of degree p (in preparation)

    Google Scholar 

  19. I. SageMath, SageMathCloud Online Computational Mathematics (2016), https://cloud.sagemath.com/

    Google Scholar 

  20. J.P. Serre, Corps Locaux, Troisième édition (Hermann, Paris, 1968). Publications de l’Université de Nancago, No. VIII

    Google Scholar 

  21. J.P. Serre, Facteurs locaux des fonctions zêta des variétés algébriques (définitions et conjectures). Séminaire Delange-Pisot-Poitou (Théorie des Nombres) 19(2), 1–15 (1969)

    Google Scholar 

  22. J.P. Serre, J. Tate, Good reduction of abelian varieties. Ann. Math. 88(3), 492–517 (1968)

    Article  MathSciNet  Google Scholar 

  23. J.H. Silverman, Advanced Topics in the Arithmetic of Elliptic Curves. Graduate Text in Mathematics, vol. 151 (Springer, New York, 1994)

    Book  Google Scholar 

  24. N.P. Smart, S-unit equations, binary forms and curves of genus 2. Proc. Lond. Math. Soc. 75(2), 271–307 (1997)

    Article  MathSciNet  Google Scholar 

  25. R. von Känel, An effective proof of the hyperelliptic Shafarevich conjecture. J. Théor. Nombres Bordeaux 26(2), 507–530 (2014)

    Article  MathSciNet  Google Scholar 

  26. S. Wewers, Deformation of tame admissible covers of curves, in Aspects of Galois Theory, ed. by H. Völklein. LMS Lecture Note Series, vol. 256 (Cambridge University Press, Cambridge, 1999), pp. 239–282

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Stefan Wewers .

Editor information

Editors and Affiliations

Rights and permissions

Reprints and permissions

Copyright information

© 2017 Springer International Publishing AG, part of Springer Nature

About this chapter

Check for updates. Verify currency and authenticity via CrossMark

Cite this chapter

Börner, M., Bouw, I.I., Wewers, S. (2017). Picard Curves with Small Conductor. In: Böckle, G., Decker, W., Malle, G. (eds) Algorithmic and Experimental Methods in Algebra, Geometry, and Number Theory. Springer, Cham. https://doi.org/10.1007/978-3-319-70566-8_4

Download citation

Publish with us

Policies and ethics