Abstract:
The reflective modular forms of orthogonal type are fundamental automorphic objects generalizing the classical Dedekind eta-function. This article describes two methods for constructing such modular forms in terms of Jacobi forms: automorphic products and Jacobi lifting. In particular, it is proved that the first non-zero Fourier–Jacobi coefficient of the Borcherds modular form $\Phi_{12}$ (the generating function of the so-called Fake Monster Lie Algebra) in any of the 23 one-dimensional cusps coincides with the Kac–Weyl denominator function of the affine algebra of the root system of the corresponding Niemeier lattice. This article gives a new simple construction of the automorphic discriminant of the moduli space of Enriques surfaces as a Jacobi lifting of the product of eight theta-functions and considers three towers of reflective modular forms. One of them, the tower of $D_8$, gives a solution to a problem of Yoshikawa (2009) concerning the construction of Lorentzian Kac–Moody algebras from the automorphic discriminants connected with del Pezzo surfaces and analytic torsions of Calabi–Yau manifolds. The article also formulates some conditions on sublattices, making it possible to produce families of ‘daughter’ reflective forms from a fixed modular form. As a result, nearly 100 such functions are constructed here.
Bibliography: 77 titles.
This work was supported by the Laboratory of Mirror Symmetry, National Research University, Higher School of Economics
(Russian Federation government grant, ag. no. 14.641.31.0001).
This publication is cited in the following 21 articles:
Haowu Wang, Brandon Williams, “The fake monster algebra and singular Borcherds products”, Advances in Mathematics, 461 (2025), 110083
Yota Maeda, “Reflective obstructions of unitary modular varieties”, Journal of Algebra, 647 (2024), 341
Bing-Xin Lao, Ruben Minasian, “Consistency of eight-dimensional supergravities: anomalies, lattices and counterterms”, J. High Energ. Phys., 2024:6 (2024)
Dmitrii Adler, Valery Gritsenko, “Modular differential equations of W(D)-invariant Jacobi forms”, Journal of Geometry and Physics, 2024, 105339
Y. Maeda, Y. Odaka, “Fano Shimura varieties with mostly branched cusps”, Birational Geometry, Kähler–Einstein Metrics and Degenerations, Springer Proceedings in Mathematics & Statistics, 409, 2023, 633
Haowu Wang, “2-Reflective Lattices of Signature (n, 2) withn≥8”, International Mathematics Research Notices, 2023:20 (2023), 17953
K. Sun, H. Wang, “Conway invariant Jacobi forms on the Leech lattice”, Forum Mathematicum, 34:6 (2022), 1591–1619
H. Wang, “Reflective modular forms on lattices of prime level”, Trans. Amer. Math. Soc., 375 (2022), 3451–3468
X. Dai, K.-I. Yoshikawa, “Analytic torsion for log-Enriques surfaces and Borcherds product”, Forum of Mathematics, Sigma, 10 (2022), E77
C. F. Cota, A. Klemm, T. Schimannek, “State counting on fibered cy 3-folds and the non-abelian weak gravity conjecture”, J. High Energy Phys., 2021, no. 5, 30
H. Wang, “Weyl invariant E-8 Jacobi forms”, Commun. Number Theory Phys., 15:3 (2021), 517–573
Dittmann M., Wang H., “Theta Blocks Related to Root Systems”, Math. Ann., 2021
H. Wang, “On some free algebras of orthogonal modular forms II”, Res. Number Theory, 7:3 (2021), 47
H. Wang, “The classification of free algebras of orthogonal modular forms”, Compos. Math., 157:9 (2021), 2026–2045
H. Wang, “Weyl invariant Jacobi forms: a new approach”, Adv. Math., 384 (2021), 107752
H. Wang, B. Williams, “On some free algebras of orthogonal modular forms”, Adv. Math., 373 (2020), 107332
V. Gritsenko, H. Wang, “Theta block conjecture for paramodular forms of weight 2”, Proc. Amer. Math. Soc., 148:5 (2020), 1863–1878
D. Adler, V. Gritsenko, “The d-8-tower of weak Jacobi forms and applications”, J. Geom. Phys., 150 (2020), 103616