Abstract
In this paper, we solve the Rankin–Selberg problem. That is, we break the well known Rankin–Selberg’s bound on the error term of the second moment of Fourier coefficients of a \({\text {GL}}(2)\) cusp form (both holomorphic and Maass), which remains its record since its birth for more than 80 years. We extend our method to deal with averages of coefficients of L-functions which can be factorized as a product of a degree one and a degree three L-functions.
Similar content being viewed by others
Notes
There is a typo in [14, eq. (20.158)].
References
Aggarwal, K.: A new subconvex bound for \({\rm GL}(3)\) L-functions in the \(t\)-aspect. Int. J. Number Theory (2020). https://doi.org/10.1142/S1793042121500275
Blomer, V.: Subconvexity for twisted L-functions on \({\rm GL}(3)\). Am. J. Math. 134(5), 1385–1421 (2012)
Blomer, V., Khan, R., Young, M.: Distribution of mass of holomorphic cusp forms. Duke Math. J. 162(14), 2609–2644 (2013)
Bourgain, J.: Decoupling exponential sums and the Riemann zeta function. J. Am. Math. Soc. 30(1), 205–224 (2017)
Friedlander, J., Iwaniec, H.: Summation formulae for coefficients of L-functions. Can. J. Math. 57(3), 494–505 (2005)
Gelbart, S., Jacquet, H.: A relation between automorphic representations of \({\rm GL}(2)\) and \({\rm GL}(3)\). Ann. Sci. École Norm. Sup. (4) 11(4), 471–542 (1978)
Goldfeld, D.: Automorphic forms and L-functions for the group \({\rm GL}(n,{\mathbb{R}})\). With an appendix by Kevin A. Broughan. Cambridge Studies in Advanced Mathematics, vol. 99, pp. xiv+493. Cambridge University Press, Cambridge (2006)
Goldfeld, D., Li, X.: Voronoi formulas on \({\rm GL}(n)\). Int. Math. Res. Not., 25 (2006) (Art. ID 86295)
Graham, S.W., Kolesnik, G.: Van der Corput’s Method of Exponential Sums. London Mathematical Society Lecture Note Series, vol. 126. Cambridge University Press, Cambridge (1991)
Huang, B.: Quantum variance for Eisenstein series. Int. Math. Res. Not. 2021(2), 1224–1248 (2019)
Huxley, M.N.: Area, Lattice Points, and Exponential Sums. London Mathematical Society Monographs. New Series, vol. 13, The Clarendon Press, Oxford University Press, New York (1996)
Ivić, A.: Large values of certain number-theoretic error terms. Acta Arith. 56, 135–159 (1990)
Ivić, A.: On the fourth moment in the Rankin–Selberg problem. Arch. Math. (Basel) 90(5), 412–419 (2008)
Iwaniec, H., Kowalski, E.: Analytic number theory, vol. 53 of American Mathematical Society Colloquium Publications. American Mathematical Society, Providence, RI (2004)
Jacquet, H., Shalika, J.: Rankin–Selberg convolutions: Archimedean theory. Festschrift in honor of I. I. Piatetski-Shapiro on the occasion of his sixtieth birthday, Part I (Ramat Aviv, 1989), Israel Math. Conf. Proc., vol. 2, pp. 125–207. Weizmann, Jerusalem (1990)
Jutila, M.: Lectures on a method in the theory of exponential sums. In: Tata Institute of Fundamental Research Lectures on Mathematics and Physics, vol. 80. Published for the Tata Institute of Fundamental Research, Bombay; Springer, Berlin (1987)
Kiral, E., Petrow, I., Young, M.: Oscillatory integrals with uniformity in parameters. J. Théor. Nombres Bordx. 31(1), 145–159 (2019)
Kumar, S., Mallesham, K., Singh, S.K.: Non-linear additive twist of Fourier coefficients of \({\rm GL}(3)\) Maass forms (2019). arXiv:1905.13109
Lau, Y.K., Lü, G.S., Wu, J.: Integral power sums of Hecke eigenvalues. Acta Arith. 150(2), 687–716 (2011)
Li, X.: The central value of the Rankin–Selberg L-functions. Geom. Funct. Anal. 18(5), 1660–1695 (2009)
Lin, Y., Sun, Q.: Analytic twists of \({\rm GL}_3 \times {\rm GL}_2\) automorphic forms. Int. Math. Res. Not. (2021). https://doi.org/10.1093/imrn/rnaa348
Miller, S., Schmid, W.: Automorphic distributions, \(L\)-functions, and Voronoi summation for \({\rm GL}(3)\). Ann. Math. (2) 164(2), 423–488 (2006)
Munshi, R.: The circle method and bounds for L-functions-III: \(t\)-aspect subconvexity for \({\rm GL}(3)\) L-functions. J. Am. Math. Soc. 28(4), 913–938 (2015)
Munshi, R.: Subconvexity for \({\rm GL}(3)\times {\rm GL}(2) \)\( L \)-functions in \( t \)-aspect (2018). arXiv:1810.00539
Rankin, R.A.: Contributions to the theory of Ramanujan’s function \(\tau (n)\) and similar arithmetical functions. I. The zeros of the function \(\sum _{n=1}^\infty \tau (n)/n^s\) on the line \({\rm Re} s=13/2\). II. The order of the Fourier coefficients of integral modular forms. Proc. Camb. Philos. Soc. 35, 351–372 (1939)
Selberg, A.: Bemerkungen über eine Dirichletsche Reihe, die mit der Theorie der Modulformen nahe verbunden ist. (German). Arch. Math. Nat. 43, 47–50 (1940)
Titchmarsh, E.C.: The theory of the Riemann zeta-function. In: Edited and with a preface by D. R. Heath-Brown, 2nd edn., pp. x+412. The Clarendon Press, Oxford University Press, New York (1986)
Valentin, B., Farrell, B.: The role of the Ramanujan conjecture in analytic number theory. Bull. Am. Math. Soc. (N.S.) 50(2), 267–320 (2013)
Acknowledgements
The author wants to thank Prof. Jianya Liu and Zeév Rudnick for their help and encouragements. He would like to thank Yongxiao Lin and Qingfeng Sun for many discussions on [5, 21]. The author started to try seriously to solve the Rankin–Selberg problem when he was a postdoc at Tel Aviv University. He likes to thank Tel Aviv Unviersity for providing a nice work environment.
Author information
Authors and Affiliations
Corresponding author
Additional information
Communicated by Kannan Soundararajan.
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
This work was supported by the Young Taishan Scholars Program of Shandong Province (Grant No. tsqn201909046), Qilu Young Scholar Program of Shandong University, and NSFC (Nos. 12001314 and 12031008)