Sparse equidistribution problems, period bounds, and subconvexity

Research paper by Akshay Venkatesh

Indexed on: 31 Jul '06Published on: 31 Jul '06Published in: Mathematics - Number Theory


We introduce a ``geometric'' method to bound periods of automorphic forms. The key features of this method are the use of equidistribution results in place of mean value theorems, and the systematic use of mixing and the spectral gap. Applications are given to equidistribution of sparse subsets of horocycles and to equidistribution of CM points; to subconvexity of the triple product period in the level aspect over number fields, which implies subconvexity for certain standard and Rankin-Selberg $L$-functions; and to bounding Fourier coefficients of automorphic forms.