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Special Values of Class Group L-Functions for CM Fields

Published online by Cambridge University Press:  20 November 2018

Riad Masri*
Affiliation:
Department of Mathematics, University of Wisconsin, Madison, WI 53706, USA, e-mail: [email protected]
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Abstract

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Abstract. Let $H$ be the Hilbert class field of a $\text{CM}$ number field $K$ with maximal totally real subfield $F$ of degree $n$ over $\mathbb{Q}$. We evaluate the second term in the Taylor expansion at $s\,=\,0$ of the Galois-equivariant $L$-function ${{\Theta }_{{{S}_{\infty }}\,}}\left( s \right)$ associated to the unramified abelian characters of $\text{Gal}\left( H/K \right)$. This is an identity in the group ring $\mathbb{C}\left[ \text{Gal}\left( H/K \right) \right]$ expressing $\Theta _{{{S}_{\infty }}}^{(n)}\,\left( 0 \right)$ as essentially a linear combination of logarithms of special values $\left\{ \Psi ({{z}_{\sigma }}) \right\}$, where $\Psi :\,{{\mathbb{H}}^{n}}\,\to \,\mathbb{R}$ is a Hilbert modular function for a congruence subgroup of $S{{L}_{2}}\left( {{\mathcal{O}}_{F}} \right)$ and $\left\{ {{z}_{\sigma }}\,:\,\sigma \,\in \,\text{Gal}\left( H/K \right) \right\}$ are $\text{CM}$ points on a universal Hilbert modular variety. We apply this result to express the relative class number ${{h}_{H}}/{{h}_{K}}$ as a rational multiple of the determinant of an $\left( {{h}_{K}}\,-\,1 \right)\,\times \,\left( {{h}_{K}}\,-\,1 \right)$ matrix of logarithms of ratios of special values $\Psi ({{z}_{\sigma }})$, thus giving rise to candidates for higher analogs of elliptic units. Finally, we obtain a product formula for $\Psi ({{z}_{\sigma }})$ in terms of exponentials of special values of $L$-functions.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 2010

References

[A] T., Asai, On a certain function analogous to log |η(z)|. Nagoya Math J. 40(1970), 193-211.Google Scholar
[B] D., Barsky, Fonctions zeta p-adiques d'une classe de rayon corps de nombres totalement réels. Groupe d'Etude d'Analyse Ultramétrique 16, Secrétariat Math., Paris, 1978.Google Scholar
[BY1] J. H., Bruinier and T., Yang, CM values of Hilbert modular functions. Invent. Math. 163(2006), no. 2, 229-288. doi:10.1007/s00222-005-0459-7Google Scholar
[BY2] J. H., Bruinier and T., Yang, Twisted Borcherds products on Hilbert modular surfaces and their CM values. Amer. J. Math. 129(2007), no. 3, 807-841.Google Scholar
[BF] D., Burns and M., Flach, Motivic L-functions and Galois module structures. Math. Ann. 305(1996), no. 1, 65-102. doi:10.1007/BF01444212Google Scholar
[CN] Cassou-Noguès, P., Valeurs aux entiers négatifs des fonctions zêta et fonctions zêta p-adiques. Invent. Math. 51(1979), no. 1, 29-59. doi:10.1007/BF01389911Google Scholar
[C] C., Chevalley, L'arithmétique dans les algèbres de matrices. Actualités Scientifiques et Industrielles 323, Hermann, Paris, 1936.Google Scholar
[Ch] T., Chinburg, On the Galois structure of algebraic integers and S-units. Invent. Math. 74(1983), no. 3, 321-349. doi:10.1007/BF01394240Google Scholar
[DR] P., Deligne and K., Ribet, Values of abelian L-functions at negative integers over totally real fields. Invent. Math. 59(1980), no. 3, 227-286. doi:10.1007/BF01453237Google Scholar
[GR] I., Gradshteyn, and I., Ryzhik, Table of Integrals, series, and products. Fourth edition, Academic Press, New York-London, 1965.Google Scholar
[K] S., Konno, On Kronecker's limit formula in a totally imaginary quadratic field over a totally real algebraic number field. J. Math. Soc. Japan 17(1965), 411-424.Google Scholar
[Kr] S., Krantz, Function theory of several complex variables. Pure and Applied Mathematics, John Wiley and Sons, Inc., New York, 1982.Google Scholar
[L1] S., Lang, Algebraic Number Theory. Addison-Wesley Publishing Co., Inc., Reading, MA, 1970.Google Scholar
[L2] S., Lang, Elliptic Functions. Graduate Texts in Mathematics 112, Springer-Verlag, New York, 1987.Google Scholar
[M] C. J., Moreno, The Chowla-Selberg formula. J. Number Theory 17(1983), no. 2, 226-245. doi:10.1016/0022-314X(83)90022-7Google Scholar
[N] J., Neukirch, Algebraic number theory. Grundlehren der Mathematischen Wissenschaften 322, Springer-Verlag, Berlin, 1999.Google Scholar
[P] C. D., Popescu, Rubin's integral refinement of the abelian Stark conjecture. In: Stark's conjectures: recent work and new directions, Contemp. Math. 358, American Mathematical Society, Providence, RI, 200, pp. 1-35.Google Scholar
[R] K., Rubin, A Stark conjecture ”;over Z“ for abelian L-functions with multiple zeros. Ann. Inst. Fourier (Grenoble) 46(1996), no. 1, 33-62.Google Scholar
[Si] C. L., Siegel, Lectures on advanced analytic number theory. Notes by S. Raghavan. Tata Institute of Fundamental Research Lectures on Mathematics 23, Tata Institute of Fundamental Research, Bombay, 1965.Google Scholar
[St1] H. M., Stark, L-functions at s = 1. I. L-functions for quadratic forms. Advances in Math. 7(1971), 301-343. doi:10.1016/S0001-8708(71)80009-9Google Scholar
[St2] H. M., Stark, L-functions at s = 1. II. Artin L-functions with rational characters. Advances in Math. 17(1975), no. 1, 60-92. doi:10.1016/0001-8708(75)90087-0Google Scholar
[St3] H. M., Stark, L-functions at s = 1. III. Totally real fields and Hilbert's twelfth problem. Advances in Math. 22(1976), no. 1, 64-84. doi:10.1016/0001-8708(76)90138-9Google Scholar
[St4] H. M., Stark, [H. M. Stark] L-functions at s = 1. IV. First derivatives at s = 0. Adv. in Math. 35(1980), no. 3, 197-235. doi:10.1016/0001-8708(80)90049-3Google Scholar
[T] J., Tate, Les conjectures de Stark sur les fonctiones L d'Artin en s = 0. Progress in Mathematics 47, Birkhäuser Boston, Inc., Boston, MA, 1984.Google Scholar
[Y] T., Yang, CM number fields and modular forms. Pure Appl. Math. Q. 1(2005), no. 2, part 1, 305-340.Google Scholar