Hostname: page-component-78c5997874-m6dg7 Total loading time: 0 Render date: 2024-11-10T13:29:13.320Z Has data issue: false hasContentIssue false

CLASS NUMBERS OF CM ALGEBRAIC TORI, CM ABELIAN VARIETIES AND COMPONENTS OF UNITARY SHIMURA VARIETIES

Published online by Cambridge University Press:  28 October 2020

JIA-WEI GUO
Affiliation:
Department of Mathematics National Taiwan University No. 1, Roosevelt Road, Section 4 Taipei 10617, Taiwanjiaweiguo312@gmail.com
NAI-HENG SHEU
Affiliation:
Department of Mathematics Indiana University Rawles Hall, 831 East 3rd Street Bloomington, Indiana 47405, USAnaihsheu@iu.edu
CHIA-FU YU*
Affiliation:
Institute of Mathematics Academia Sinica and NCTS 6F Astronomy Mathematics Building, No. 1, Roosevelt Road, Section 4 Taipei 10617, Taiwan

Abstract

We give a formula for the class number of an arbitrary complex mutliplication (CM) algebraic torus over $\mathbb {Q}$ . This is proved based on results of Ono and Shyr. As applications, we give formulas for numbers of polarized CM abelian varieties, of connected components of unitary Shimura varieties and of certain polarized abelian varieties over finite fields. We also give a second proof of our main result.

Type
Article
Copyright
© The Authors, 2020. Foundation Nagoya Mathematical is the exclusive licensee of this article

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Achter, J. D., Irreducibility of Newton strata in $\ GU\left(1,n-1\right)$ Shimura varieties , Proc. Amer. Math. Soc. Ser. B 1 (2014), 7988.CrossRefGoogle Scholar
Achter, J., Altug, S. A., Gordon, J., Li, W.-W., and Rüd, T., Counting abelian varieties over finite fields via Frobenius densities, preprint, 2019, arXiv:1905.11603.Google Scholar
Bültel, O., and Wedhorn, T., Congruence relations for Shimura varieties associated to some unitary groups , J. Inst. Math. Jussieu 5 (2006), 229261.CrossRefGoogle Scholar
Daw, C., On torsion of class groups of CM tori , Mathematika 58 (2012), 305318.CrossRefGoogle Scholar
Deligne, P., Travaux de Shimura . In Séminaire Bourbaki, 23ème année (1970/71), Exp. No. 389. Lecture Notes in Math. 244, Springer, Berlin, 1971.Google Scholar
Gan, W. T., and Yu, J.-K., Group schemes and local densities , Duke Math. J. 105 (2000), 497524.CrossRefGoogle Scholar
González-Avilés, C. D., Chevalley’s ambiguous class number formula for an arbitrary torus , Math. Res. Lett. 15 (2008), 11491165.CrossRefGoogle Scholar
González-Avilés, C. D., On Néron-Raynaud class groups of tori and the capitulation problem , J. Reine Angew. Math. 648 (2010), 149182.Google Scholar
Herglotz, G., Über einen Dirichletschen Satz , Math. Z. 12 (1922), 255261.CrossRefGoogle Scholar
Katayama, S.-I., Isogenous tori and the class number formulae , J. Math. Kyoto Univ. 31 (1991), 679694.Google Scholar
Kottwitz, R. E., Tamagawa numbers , Ann. Math 127 (1988), 629646.CrossRefGoogle Scholar
Kottwitz, R. E., Points on some Shimura varieties over finite fields , J. Amer. Math. Soc. 5 (1992), 373444.CrossRefGoogle Scholar
Lan, K.-W., Arithmetic Compactifications of PEL-type Shimura Varieties, London Mathematical Society Monographs Series, 36 , Princeton University Press, Princeton, NJ, 2013.Google Scholar
Lang, S., Algebraic Number Theory, Graduate Texts in Mathematics, 110 , 2nd ed., Springer, New York, NY, 1994.CrossRefGoogle Scholar
Marseglia, S., Computing square-free polarized abelian varieties over finite fields, preprint, 2018, arXiv:1805.10223. To appear in Mathemtics of Computation.Google Scholar
Morishita, M., On $S$ -class number relations of algebraic tori in Galois extensions of global fields , Nagoya Math. J. 124 (1991), 133144.CrossRefGoogle Scholar
Neukirch, J., Algebraic Number Theory, Grundlehren der Mathematischen Wissenschaften, 322 , Springer, Berlin, Germany, 1999. Translated from the 1992 German original and with a note by Norbert Schappacher.Google Scholar
Ono, T., Arithmetic of algebraic tori , Ann. Math 74 (1961), 101139.CrossRefGoogle Scholar
Ono, T., On the Tamagawa number of algebraic tori , Ann. Math 78 (1963), 4773.CrossRefGoogle Scholar
Ono, T., On Tamagawa numbers . In Algebraic Groups and Discontinuous Subgroups (Proc. Sympos. Pure Math., Boulder, Colo., 1965), American Mathematical Society, Providence, RI, 1966, 122132.CrossRefGoogle Scholar
Ono, T., On some class number relations for Galois extensions , Nagoya Math. J. 107 (1987), 121133.CrossRefGoogle Scholar
Platonov, V., and Rapinchuk, A., Algebraic Groups and Number Theory, Pure and Applied Mathematics, 139 , Academic Press, Boston, MA, 1994. Translated from the 1991 Russian original by Rachel Rowen.Google Scholar
Shyr, J. M., On some class number relations of algebraic tori , Michigan Math. J. 24 (1977), 365377.CrossRefGoogle Scholar
Tran, M.-H., A formula for the $S$ -class number of an algebraic torus , J. Number Theory 181 (2017), 218239.CrossRefGoogle Scholar
Ullmo, E., and Yafaev, A., Nombre de classes des tores de multiplication complexe et bornes inférieures pour les orbites galoisiennes de points spéciaux , Bull. Soc. Math. France 143 (2015), 197228.CrossRefGoogle Scholar
Washington, L. C., Introduction to Cyclotomic Fields, Graduate Texts in Mathematics, 83 , 2nd ed., Springer, New York, NY, 1997.CrossRefGoogle Scholar
Weil, A., Adèles et groupes algébriques . In Séminaire Bourbaki, vol. 5, Soc. Math. France, Paris, 1995, 249257.Google Scholar
Xue, J., Yang, T.-C., and Yu, C.-F., Numerical invariants of totally imaginary quadratic $\mathbb{Z}\left[\sqrt{p}\right]$ -orders , Taiwanese J. Math 20 (2016), 723741.CrossRefGoogle Scholar
Xue, J., and Yu, C.-F., On counting certain abelian varieties over finite fields, preprints, 2018, to appear in Acta Math. Sin. (Engl. Ser.).Google Scholar
Yu, C.-F., Connected components of certain complex Shimura varieties. In preparation.Google Scholar
Yu, C.-F., Simple mass formulas on Shimura varieties of PEL-type , Forum Math. 22 (2010):565582,CrossRefGoogle Scholar
Zhang, S.-W., Equidistribution of CM-points on quaternion Shimura varieties , Int. Math. Res. Not. 59 (2005), 36573689.CrossRefGoogle Scholar