Abstract
A “shear” is a unipotent translate of a cuspidal geodesic ray in the quotient of the hyperbolic plane by a non-uniform discrete subgroup of \({\text {PSL}}(2,\mathbb {R})\), possibly of infinite co-volume. We prove the regularized equidistribution of shears under large translates with effective (that is, power saving) rates. We also give applications to weighted second moments of GL(2) automorphic L-functions, and to counting lattice points on locally affine symmetric spaces.
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Notes
By “spectral gap” we always mean the distance between the first eigenvalue \(\lambda _{1}\) and the base eigenvalue \(\lambda _{0}\) of the hyperbolic Laplacian; see Sect. 2.5.
Of course one can instead order by wordlength in \(\Gamma \), as is done in [3], to restore equidistribution and apply the Affine Sieve.
Equivalently, non-elementary, that is, not virtually abelian.
For surface groups, being geometrically finite is equivalent to being finitely generated.
Roughly speaking, the critical exponent measures the asymptotic growth rate of \(\Gamma \); see Sect. 2.1.
Added in print: In private communication, Hee Oh has notified us that she and Nimish Shah have an unpublished manuscript in which they obtain a result similar to (1.16) in the lattice case.
Recall that the limit set, \(\Lambda \), of \(\Gamma \) decomposes disjointly into cusps (i.e., parabolic fixed points) and radial limit points (also called “points of approximation”); the complement \(\partial \mathbb {H}{\setminus }\Lambda \) is called the free boundary (which is empty if \(\Gamma \) is a lattice). See §2.1.
We should note that we are using a non-standard definition for the Eisenstein series, where we multiply the series by \(\tfrac{1}{\omega }\) instead of by \(\tfrac{1}{\omega ^s}\). Using the standard definition instead will result in minor changes to the regularized Eisenstein series in the lattice case.
References
Blomer, V., Brumley, F., Kontorovich, A., Templier, N.: Bounding hyperbolic and spherical coefficients of Maass forms. J. Théor. Nombres Bordeaux 26(3), 559–579 (2014)
Beardon, Alan F.: The Geometry of Discrete Groups, volume 91 of Graduate Texts in Mathematics. Springer, New York (1983)
Bourgain, J., Gamburd, A., Sarnak, P.: Affine linear sieve, expanders, and sum-product. Invent. Math. 179(3), 559–644 (2010)
Bourgain, J., Gamburd, A., Sarnak, P.: Generalization of Selberg’s 3/16th theorem and affine sieve. Acta Math 207, 255–290 (2011)
Bourgain, J., Kontorovich, A.: The affine sieve beyond expansion I: Thin hypotenuses. Int. Math. Res. Not. IMRN 19, 9175–9205 (2015)
Bourgain, J., Kontorovich, A., Sarnak, P.: Sector estimates for hyperbolic isometries. GAFA 20(5), 1175–1200 (2010)
Blomer, Valentin: Sums of Hecke eigenvalues over values of quadratic polynomials. Int. Math. Res. Not. IMRN, (16):Art. ID rnn059. 29, (2008)
Bernstein, Joseph, Reznikov, André: Sobolev norms of automorphic functionals and Fourier coefficients of cusp forms. C. R. Acad. Sci. Paris Sér. I Math. 327(2), 111–116 (1998)
Cowling, M., Haagerup, U., Howe, R.: Almost \(L^2\) matrix coefficients. J. Reine Angew. Math. 387, 97–110 (1988)
Delsarte, J.: Sur le gitter fuchsien. C. R. Acad. Sci. Paris 214, 147–179 (1942)
Deligne, P.: La conjecture de Weil. I. Inst. Hautes Études Sci. Publ. Math. 43, 273–307 (1974)
Diaconu, A., Garrett, P.: Subconvexity bounds for automorphic \(L\)-functions. J. Inst. Math. Jussieu 9(1), 95–124 (2010)
Diaconu, A., Garrett, P., Goldfeld, D.: Moments for \(L\)-functions for \(GL_r\times GL_{r-1}\). In: Contributions in analytic and algebraic number theory, volume 9 of Springer Proc. Math., pp. 197–227. Springer, New York (2012)
Dolgopyat, Dmitry: On decay of correlations in Anosov flows. Ann. of Math. (2) 147(2), 357–390 (1998)
Duke, W., Rudnick, Z., Sarnak, P.: Density of integer points on affine homogeneous varieties. Duke Math. J. 71(1), 143–179 (1993)
Eskin, A., McMullen, C.: Mixing, counting and equidistribution in lie groups. Duke Math. J. 71, 143–180 (1993)
Gelfand, I.M., Graev, M.I., Pjateckii-Shapiro, I.I.: Teoriya predstavlenii i avtomorfnye funktsii. Generalized functions, No. 6. Izdat. Nauka, Moscow, (1966)
Gelbart, S., Jacquet, H.: A relation between automorphic representations of \(\text{ GL }(2)\) and \(\text{ GL }(3)\). Ann. Sci. École Norm. Sup. (4) 11(4), 471–542 (1978)
Good, A.: The convolution method for Dirichlet series. In: The Selberg trace formula and related topics (Brunswick, Maine, 1984), volume 53 of Contemp. Math., pages 207–214. Amer. Math. Soc., Providence, RI, (1986)
Ghosh, A., Reznikov, A., Sarnak, P.: Nodal domains of Maass forms I. Geom. Funct. Anal. 23(5), 1515–1568 (2013)
Hong, J., Kontorovich, A.: Almost prime coordinates for anisotropic and thin pythagorean orbits. Israel J. Math. 209(1), 397–420 (2015)
Hulse, Thomas A., Kiral, E. Mehmet, Kuan, Chan Ieong, Lim, Li-Mei: Counting square discriminants, 2013. Preprint, arXiv:1307.6606
Hooley, C.: On the number of divisors of a quadratic polynomial. Acta Math. 110, 97–114 (1963)
Huber, H.: über eine neue Klasse automorpher Funktionen und ein Gitterpunktproblem in der hyperbolischen Ebene. i. Comment. Math. Helv. 30, 20–62 (1956)
Iwaniec, H., Kowalski, E.: Analytic number theory, volume 53 of American Mathematical Society Colloquium Publications. American Mathematical Society, Providence, RI (2004)
Iwaniec, H.: Topics in classical automorphic forms. American Mathematical Society, Providence, RI (1997)
Kontorovich, A., Oh, H.: Almost prime Pythagorean triples in thin orbits. J. reine angew. Math. 667, 89–131 (2012). arXiv:1001.0370
Kontorovich, A.: The hyperbolic lattice point count in infinite volume with applications to sieves. Duke J. Math. 149(1), 1–36 (2009). arXiv:0712.1391
Kontorovich, A.: Levels of distribution and the affine sieve. Ann. Fac. Sci. Toulouse Math. (6) 23(5), 933–966 (2014)
Kim, H., Sarnak, P.: Refined estimates towards the Ramanujan and Selberg conjectures. J. Amer. Math. Soc. 16(1), 175–181 (2003)
Lax, P.D., Phillips, R.S.: The asymptotic distribution of lattice points in Euclidean and non-Euclidean space. Journal of Functional Analysis 46, 280–350 (1982)
Liu, J., Sarnak, P.: Integral points on quadrics in three variables whose coordinates have few prime factors. Israel J. Math 178, 393–426 (2010)
Margulis, G.A.: On some aspects of the theory of Anosov systems. Springer Monographs in Mathematics. Springer-Verlag, Berlin, 2004. With a survey by Richard Sharp: Periodic orbits of hyperbolic flows, Translated from the Russian by Valentina Vladimirovna Szulikowska
Mohammadi, A., Oh, H.: Matrix coefficients, counting and primes for orbits of geometrically finite groups, (2013). To appear, JEMS
Michel, P., Venkatesh, A.: The subconvexity problem for \(\text{ GL }_2\). Publ. Math. Inst. Hautes Études Sci. 111, 171–271 (2010)
Naud, F.: Expanding maps on Cantor sets and analytic continuation of zeta functions. Ann. Sci. École Norm. Sup. (4) 38(1), 116–153 (2005)
Nevo, A., Sarnak, P.: Prime and almost prime integral points on principal homogeneous spaces. Acta Math. 205(2), 361–402 (2010)
Oh, H., Shah, N.A.: Equidistribution and counting for orbits of geometrically finite hyperbolic groups. J. Amer. Math. Soc. 26(2), 511–562 (2013)
Oh, H., Shah, N.A.: Limits of translates of divergent geodesics and integral points on one-sheeted hyperboloids. Israel J. Math. 199(2), 915–931 (2014)
Patterson, S.J.: The Laplacian operator on a Riemann surface. Compositio Math. 31(1), 83–107 (1975)
Patterson, S.J.: The limit set of a Fuchsian group. Acta Mathematica 136, 241–273 (1976)
Petridis, Y.N., Sarnak, P.: Quantum unique ergodicity for \(\text{ SL }_2({O})\backslash {\bf H}^3\) and estimates for \(L\)-functions. J. Evol. Equ. 1(3), 277–290 (2001)
Sarnak, P.: Asymptotic behavior of periodic orbits of the horocycle flow and Eisenstein series. Comm. Pure Appl. Math. 34(6), 719–739 (1981)
Sarnak, P.: Additive number theory and Maass forms. In: Number theory (New York, 1982), vol. 1052 of Lecture Notes in Math., pp. 286–309. Springer, Berlin (1984)
Sarnak, P.C.: Fourth moments of grossencharakteren zeta functions. Comm. Pure Appl. Math. 38, 167–178 (1985)
Selberg, A.: Harmonic analysis and discontinuous groups in weakly symmetric Riemannian spaces with applications to Dirichlet series. J. Indian Math. Soc. (N.S.) 20, 47–87 (1956)
Shalom, Y.: Rigidity, unitary representations of semisimple groups, and fundamental groups of manifolds with rank one transformation group. Ann. of Math. (2) 152(1), 113–182 (2000)
Strombergsson, A.: On the uniform equidistribution of long closed horocycles. Duke Math. J. 123, 507–547 (2004)
Sarnak, Peter, Ubis, Adrián: The horocycle flow at prime times. J. Math. Pures Appl. (9) 103(2), 575–618 (2015)
Sullivan, D.: Entropy, Hausdorff measures old and new, and limit sets of geometrically finite Kleinian groups. Acta Math. 153(3–4), 259–277 (1984)
Titchmarsh, E.C.: The Theory of the Riemann Zeta-Function. Oxford Univ. Press, London/New York, Oxford (1951)
Templier, N., Tsimerman, J.: Non-split sums of coefficients of \(GL(2)\)-automorphic forms. Israel J. Math. 195(2), 677–723 (2013)
Venkatesh, A.: Sparse equidistribution problems, period bounds and subconvexity. Ann. of Math. (2) 172(2), 989–1094 (2010)
Zagier, D.: Eisenstein series and the Riemann zeta function. In: Automorphic forms, representation theory and arithmetic (Bombay, 1979), volume 10 of Tata Inst. Fund. Res. Studies in Math., pages 275–301. Tata Inst. Fundamental Res., Bombay, (1981)
Acknowledgements
The authors would like to express their gratitude to Jens Marklof, Curt McMullen, and Peter Sarnak for many enlightening comments and suggestions. The second author would especially like to thank Valentin Blomer, Farrell Brumley, and Nicolas Templier for many hours of discussion about this problem; see also the related work in [1].
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Communicated by A. Venkatesh.
Kelmer is partially supported by NSF Grant DMS-1237412 and NSF Grant DMS-1401747.
Kontorovich is partially supported by an NSF CAREER Grant DMS-1254788/DMS-1455705, an NSF FRG Grant DMS-1463940, and an Alfred P. Sloan Research Fellowship.
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Kelmer, D., Kontorovich, A. Effective equidistribution of shears and applications. Math. Ann. 370, 381–421 (2018). https://doi.org/10.1007/s00208-017-1580-9
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DOI: https://doi.org/10.1007/s00208-017-1580-9