Abstract
Let F/k be a finite abelian extension of number fields with k imaginary quadratic. Let OF be the ring of integers of F and n ⩾ 2 a rational integer. We construct a submodule in the higher odd-degree algebraic K-groups of OF using corresponding Gross’s special elements. We show that this submodule is of finite index and prove that this index can be computed using the higher “twisted” class number of F, which is the cardinal of the finite algebraic K-group K2n−2(OF).
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References
A. Borel: Cohomologie de SLn et valeurs de fonctions zeta aux points entiers. Ann. Sc. Norm. Super. Pisa, Cl. Sci., IV. Ser. 4 (1977), 613–636. (In French.)
N. Bourbaki: Elements of Mathematics: Commutative Algebra. Hermann, Paris, 1972.
J. I. Burgos Gil: The Regulators of Beilinson and Borel. CRM Monograph Series 15. AMS, Providence, 2002.
C. Deninger: Higher regulators and Hecke L-series of imaginary quadratic fields. II. Ann. Math. (2) 132 (1990), 131–158.
S. El Boukhari: Fitting ideals of isotypic parts of even K-groups. Manuscr. Math. 157 (2018), 23–49.
S. El Boukhari: Higher Stickelberger ideals and even K-groups. Proc. Am. Math. Soc. 150 (2022), 3231–3239.
S. El Boukhari: On a Gross conjecture over imaginary quadratic fields. Available at https://arxiv.org/abs/2302.04049 (2023), 17 pages.
M. Flach: The equivariant Tamagawa number conjecture: A survey. Stark’s Conjectures: Recent Work and New Directions. Contemporary Mathematics 358. AMS, Providence, 2004, pp. 79–125.
E. Ghate: Vandiver’s conjecture via K-theory. Cyclotomic Fields and Related Topics. Bhaskaracharya Pratishthana, Pune, 2000, pp. 285–298.
B. H. Gross: On the values of Artin L-functions. Pure Appl. Math. Q. 1 (2005), 1–13.
J. Johnson-Leung: The local equivariant Tamagawa number conjecture for almost abelian extensions. Women in Numbers 2: Research Directions in Number Theory. Contemporary Mathematics 606. AMS, Providence, 2013, pp. 1–27.
H. Klingen: Über die Werte der Dedekindschen Zetafunktion. Math. Ann. 145 (1962), 265–272. (In German.)
M. Kolster, T. Nguyen Quang Do, V. Fleckinger: Twisted S-units, p-adic class number formulas, and the Lichtenbaum conjectures. Duke Math. J. 84 (1996), 679–717.
M. Kurihara: Some remarks on conjectures about cyclotomic fields and K-groups of Z. Compos. Math. 81 (1992), 223–236.
B. Mazur, A. Wiles: Class fields of abelian extensions of ℚ. Invent. Math. 76 (1984), 179–331.
J. Neukirch: The Beilinson conjecture for algebraic number fields. Beilinson’s Conjectures on Special Values of L-Functions. Perspectives in Mathematics 4. Academic Press, Boston, 1988, pp. 193–247.
J. Neukirch, A. Schmidt, K. Wingberg: Cohomology of Number Fields. Grundlehren der Mathematischen Wissenschaften 323. Springer, Berlin, 2000.
A. Nickel: Leading terms of Artin L-series at negative integers and annihilation of higher K-groups. Math. Proc. Camb. Philos. Soc. 151 (2011), 1–22.
M. Rapoport, N. Schappacher, P. Schneider (eds.): Beilinson’s Conjectures on Special Values of L-Functions. Perspectives in Mathematics 4. Academic Press, Boston, 1988.
C. L. Siegel: Über die Fourierschen Koeffizienten von Modulformen. Nachr. Akad. Wiss. Göttingen, II. Math.-Phys. Kl. 1970 (1970), 15–56. (In German.)
W. Sinnott: On the Stickelberger ideal and the circular units of an abelian field. Invent. Math. 62 (1980), 181–234.
V. P. Snaith: Stark’s conjecture and new Stickelberger phenomena. Can. J. Math. 58 (2006), 419–448.
C. Soulé: K-théorie des anneaux d’entiers de corps de nombres et cohomologie étale. Invent. Math. 55 (1979), 251–295. (In French.)
C. Soulé: On higher p-adic regulators. Algebraic K-Theory. Lecture Notes in Mathematics 854. Springer, Berlin, 1981, pp. 372–401.
C. Soulé: Perfect forms and Vandiver conjecture. J. Reine Angew. Math. 517 (1999), 209–221.
C. Sun: The Lichtenbaum conjecture for abelian extension of imaginary quadratic fields. Available at https://arxiv.org/abs/2112.12314 (2021), 17 pages.
J. Tate: Les conjectures de Stark sur les fonctions L d’Artin en s = 0. Progress in Mathematics 47. Birkhäuser, Boston, 1984. (In French.)
S. Viguié: Index-modules and applications. Manuscr. Math. 136 (2011), 445–460.
V. Voevodsky: On motivic cohomology with ℤ/l-coefficients. Ann. Math. (2) 174 (2011), 401–438.
A. Wiles: The Iwasawa conjecture for totally real fields. Ann. Math. (2) 131 (1990), 493–540.
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El Boukhari, S. A twisted class number formula and Gross’s special units over an imaginary quadratic field. Czech Math J 73, 1333–1347 (2023). https://doi.org/10.21136/CMJ.2023.0067-23
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DOI: https://doi.org/10.21136/CMJ.2023.0067-23
Keywords
- algebraic K-theory
- Dedekind zeta function
- Artin L-function
- Beilinson regulator
- generalized index
- Lichtenbaum conjecture