Symmetry, Integrability and Geometry: Methods and Applications (SIGMA)


SIGMA 14 (2018), 097, 12 pages      arXiv:1805.04233      https://doi.org/10.3842/SIGMA.2018.097
Contribution to the Special Issue on Modular Forms and String Theory in honor of Noriko Yui

A Note on the Formal Groups of Weighted Delsarte Threefolds

Yasuhiro Goto
Department of Mathematics, Hokkaido University of Education, 1-2 Hachiman-cho, Hakodate 040-8567 Japan

Received May 11, 2018, in final form August 30, 2018; Published online September 12, 2018

Abstract
One-dimensional formal groups over an algebraically closed field of positive characteristic are classified by their height. In the case of $K3$ surfaces, the height of their formal groups takes integer values between $1$ and $10$, or $\infty$. For Calabi-Yau threefolds, the height is bounded by $h^{1,2}+1$ if it is finite, where $h^{1,2}$ is a Hodge number. At present, there are only a limited number of concrete examples for explicit values or the distribution of the height. In this paper, we consider Calabi-Yau threefolds arising from weighted Delsarte threefolds in positive characteristic. We describe an algorithm for computing the height of their formal groups and carry out calculations with various Calabi-Yau threefolds of Delsarte type.

Key words: Artin-Mazur formal groups; Calabi-Yau threefolds; weighted Delsarte varieties.

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References

  1. Artin M., Supersingular $K3$ surfaces, Ann. Sci. École Norm. Sup. (4) 7 (1974), 543-567.
  2. Artin M., Mazur B., Formal groups arising from algebraic varieties, Ann. Sci. École Norm. Sup. (4) 10 (1977), 87-131.
  3. Delsarte J., Nombre de solutions des équations polynomiales sur un corps fini, in Séminaire Bourbaki, Vol. 1, Soc. Math. France, Paris, 1995, Exp. No. 39, 321-329.
  4. Dimca A., Singularities and coverings of weighted complete intersections, J. Reine Angew. Math. 366 (1986), 184-193.
  5. Dolgachev I., Weighted projective varieties, in Group Actions and Vector Fields (Vancouver, B.C., 1981), Lecture Notes in Math., Vol. 956, Springer, Berlin, 1982, 34-71.
  6. Goto Y., Arithmetic of weighted diagonal surfaces over finite fields, J. Number Theory 59 (1996), 37-81.
  7. Goto Y., The Artin invariant of supersingular weighted Delsarte $K3$ surfaces, J. Math. Kyoto Univ. 36 (1996), 359-363.
  8. Goto Y., A note on the height of the formal Brauer group of a $K3$ surface, Canad. Math. Bull. 47 (2004), 22-29.
  9. Goto Y., Kloosterman R., Yui N., Zeta-functions of certain $K3$-fibered Calabi-Yau threefolds, Internat. J. Math. 22 (2011), 67-129, arXiv:0911.0783.
  10. Greene B.R., Roan S.-S., Yau S.-T., Geometric singularities and spectra of Landau-Ginzburg models, Comm. Math. Phys. 142 (1991), 245-259.
  11. Katz N.M., On the intersection matrix of a hypersurface, Ann. Sci. École Norm. Sup. (4) 2 (1969), 583-598.
  12. Kreuzer M., Skarke H., On the classification of quasihomogeneous functions, Comm. Math. Phys. 150 (1992), 137-147, hep-th/9202039.
  13. Shioda T., The Hodge conjecture for Fermat varieties, Math. Ann. 245 (1979), 175-184.
  14. Shioda T., An explicit algorithm for computing the Picard number of certain algebraic surfaces, Amer. J. Math. 108 (1986), 415-432.
  15. Shioda T., Katsura T., On Fermat varieties, Tôhoku Math. J. 31 (1979), 97-115.
  16. Stienstra J., Formal group laws arising from algebraic varieties, Amer. J. Math. 109 (1987), 907-925.
  17. Suwa N., Yui N., Arithmetic of certain algebraic surfaces over finite fields, in Number Theory (New York, 1985/1988), Lecture Notes in Math., Vol. 1383, Springer, Berlin, 1989, 186-256.
  18. van der Geer G., Katsura T., On the height of Calabi-Yau varieties in positive characteristic, Doc. Math. 8 (2003), 97-113, math.AG/0302023.
  19. Yui N., Formal Brauer groups arising from certain weighted $K3$ surfaces, J. Pure Appl. Algebra 142 (1999), 271-296.
  20. Yui N., The arithmetic of certain Calabi-Yau varieties over number fields, in The Arithmetic and Geometry of Algebraic Cycles (Banff, AB, 1998), NATO Sci. Ser. C Math. Phys. Sci., Vol. 548, Kluwer Acad. Publ., Dordrecht, 2000, 515-560.

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