{ "id": "1512.05502", "version": "v1", "published": "2015-12-17T09:17:05.000Z", "updated": "2015-12-17T09:17:05.000Z", "title": "Short-Interval Averages of Sums of Fourier Coefficients of Cusp Forms", "authors": [ "Thomas A. Hulse", "Chan Ieong Kuan", "David Lowry-Duda", "Alexander Walker" ], "categories": [ "math.NT" ], "abstract": "Let $f$ be a weight $k$ holomorphic cusp form of level one, and let $S_f(n)$ denote the sum of the first $n$ Fourier coefficients of $f$. In analogy with Dirichlet's divisor problem, it is conjectured that $S_f(X) \\ll X^{\\frac{k-1}{2} + \\frac{1}{4} + \\epsilon}$. Understanding and bounding $S_f(X)$ has been a very active area of research. The current best bound for individual $S_f(X)$ is $S_f(X) \\ll X^{\\frac{k-1}{2} + \\frac{1}{3}} (\\log X)^{-0.1185}$ from Wu. Chandrasekharan and Narasimhan showed that the Classical Conjecture for $S_f(X)$ holds on average over intervals of length $X$. Jutila improved this result to show that the Classical Conjecture for $S_f(X)$ holds on average over short intervals of length $X^{\\frac{3}{4} + \\epsilon}$. Building on the results and analytic information about $\\sum \\lvert S_f(n) \\rvert^2 n^{-(s + k - 1)}$ from our recent paper, we further improve these results to show that the Classical Conjecture for $S_f(X)$ holds on average over short intervals of length approximately $X^{\\frac{2}{3} + \\epsilon}$.", "revisions": [ { "version": "v1", "updated": "2015-12-17T09:17:05.000Z" } ], "analyses": { "subjects": [ "11F30" ], "keywords": [ "fourier coefficients", "short-interval averages", "classical conjecture", "short intervals", "current best bound" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2015arXiv151205502H" } } }