[Choix de signes dans l’AGM pour les thêta constantes en genre deux]
Les algorithmes existants pour le calcul de thêta-constantes en genre en temps quasilinéaire utilisent des suites de Borchardt, un analogue de la moyenne arithmético-géométrique pour quatre nombres complexes. Dans cet article, nous montrons que ces suites de Borchardt sont constituées uniquement de bons choix de signes, comme c’est le cas en genre . Ce résultat permet de lever les indéterminations de signes lors du calcul de thêta-constantes en genre sans recours à l’intégration numérique.
Existing algorithms to compute genus theta constants in quasi-linear time use Borchardt sequences, an analogue of the arithmetic-geometric mean for four complex numbers. In this paper, we show that these Borchardt sequences are only given by good choices of square roots, as in the genus case. This removes the sign indeterminacies when computing genus theta constants without relying on numerical integration.
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Mots clés : Theta functions, Genus $2$, Algorithms, Borchardt mean
Jean Kieffer 1
@article{PMB_2022____37_0, author = {Jean Kieffer}, title = {Sign choices in the {AGM} for genus two theta constants}, journal = {Publications math\'ematiques de Besan\c{c}on. Alg\`ebre et th\'eorie des nombres}, pages = {37--58}, publisher = {Presses universitaires de Franche-Comt\'e}, year = {2022}, doi = {10.5802/pmb.45}, language = {en}, url = {https://pmb.centre-mersenne.org/articles/10.5802/pmb.45/} }
TY - JOUR AU - Jean Kieffer TI - Sign choices in the AGM for genus two theta constants JO - Publications mathématiques de Besançon. Algèbre et théorie des nombres PY - 2022 SP - 37 EP - 58 PB - Presses universitaires de Franche-Comté UR - https://pmb.centre-mersenne.org/articles/10.5802/pmb.45/ DO - 10.5802/pmb.45 LA - en ID - PMB_2022____37_0 ER -
%0 Journal Article %A Jean Kieffer %T Sign choices in the AGM for genus two theta constants %J Publications mathématiques de Besançon. Algèbre et théorie des nombres %D 2022 %P 37-58 %I Presses universitaires de Franche-Comté %U https://pmb.centre-mersenne.org/articles/10.5802/pmb.45/ %R 10.5802/pmb.45 %G en %F PMB_2022____37_0
Jean Kieffer. Sign choices in the AGM for genus two theta constants. Publications mathématiques de Besançon. Algèbre et théorie des nombres (2022), pp. 37-58. doi : 10.5802/pmb.45. https://pmb.centre-mersenne.org/articles/10.5802/pmb.45/
[1] Theorie des arithmetisch-geometrisches Mittels aus vier Elementen, Gesammelte Werke, Reimer, 1888, pp. 373-431
[2] Moyenne arithmético-géométrique et périodes de courbes de genre 1 et 2, Gaz. Math., Soc. Math. Fr., Volume 38 (1988), pp. 36-64 | Zbl
[3] The arithmetic-geometric mean of Gauss, Enseign. Math., Volume 30 (1984), pp. 275-330 | MR | Zbl
[4] Moyenne arithmético-géométrique, suites de Borchardt et applications, Ph. D. Thesis, École polytechnique (2006)
[5] Fast evaluation of modular functions using Newton iterations and the AGM, Math. Comput., Volume 80 (2011) no. 275, pp. 1823-1847 | DOI | MR | Zbl
[6] The complexity of class polynomial computation via floating point approximations, Math. Comput., Volume 78 (2009) no. 266, pp. 1089-1107 | DOI | MR | Zbl
[7] Computing modular polynomials in quasi-linear time, Math. Comput., Volume 78 (2009) no. 267, pp. 1809-1824 | DOI | MR | Zbl
[8] Computing class polynomials for abelian surfaces, Exp. Math., Volume 23 (2014), pp. 129-145 | DOI | MR | Zbl
[9] On the variety associated to the ring of theta constants in genus 3, Am. J. Math., Volume 141 (2019) no. 3, pp. 705-732 | DOI | MR | Zbl
[10] Werke, Dietrich, 1868
[11] Bad reduction of genus 2 curves with CM Jacobian varieties, Compos. Math., Volume 153 (2017) no. 12, pp. 2534-2576 | DOI | MR | Zbl
[12] GeoGebra 6.0.588.0, 2020
[13] On the graded ring of theta-constants, Am. J. Math., Volume 86 (1964) no. 1, pp. 219-246 | DOI | MR | Zbl
[14] On the graded ring of theta-constants (II), Am. J. Math., Volume 88 (1966) no. 1, pp. 221-236 | DOI | MR | Zbl
[15] Theta functions, Springer, 1972 | DOI | MR
[16] Higher genus arithmetic-geometric means, Ramanujan J., Volume 17 (2008) no. 1, pp. 1-17 | DOI | MR | Zbl
[17] Introductory lectures on Siegel modular forms, Cambridge Studies in Advanced Mathematics, 20, Cambridge University Press, 1990 | DOI
[18] Computing Jacobi’s in quasi-linear time, Math. Comput., Volume 87 (2018), pp. 1479-1508 | DOI | MR | Zbl
[19] Computing theta functions in quasi-linear time in genus 2 and above, LMS J. Comput. Math., Volume 19A (2016), pp. 163-177 special issue: Algorithmic Number Theory Symposium (ANTS XII) | DOI | MR | Zbl
[20] A quasi-linear time algorithm for computing modular polynomials in dimension 2, LMS J. Comput. Math., Volume 18 (2015), pp. 603-632 | DOI | MR | Zbl
[21] Modular polynomials on Hilbert surfaces, J. Number Theory, Volume 216 (2020), pp. 403-459 | DOI | MR | Zbl
[22] Computing period matrices and the Abel–Jacobi map of superelliptic curves, Math. Comput., Volume 88 (2019) no. 316, pp. 847-888 | DOI | MR | Zbl
[23] Tata lectures on theta. I, Progress in Mathematics, 28, Birkhäuser, 1983 | DOI | MR
[24] Complex multiplication of abelian surfaces, Ph. D. Thesis, Universiteit Leiden (2010)
[25] Computing Igusa class polynomials, Math. Comput., Volume 83 (2014), pp. 275-309 | DOI | MR | Zbl
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