Vanishing and Non-Vanishing Dirichlet Twists of L-Functions of Elliptic Curves

Let L(E/Q,s) be the L-function of an elliptic curve E defined over the rational field Q. We examine the vanishing and non-vanishing of the central values L(E,1,\chi) of the twisted L-function as \chi ranges over Dirichlet characters of given order.Comment: To appear in Journal of the London Mathematical Societ

Simultaneous nonvanishing of Dirichlet LL-functions and twists of Hecke-Maass L-functions

We prove that given a Hecke-Maass form $f$ for $\text{SL}(2, \mathbb{Z})$ and a sufficiently large prime $q$, there exists a primitive Dirichlet character $\chi$ of conductor $q$ such that the $L$-values $L(\tfrac{1}{2}, f \otimes \chi)$ and $L(\tfrac{1}{2}, \chi)$ do not vanish. We expect the same method to work for any large integer $q$

Mean values with cubic characters

We investigate various mean value problems involving order three primitive Dirichlet characters. In particular, we obtain an asymptotic formula for the first moment of central values of the Dirichlet L-functions associated to this family, with a power saving in the error term. We also obtain a large-sieve type result for order three (and six) Dirichlet characters.Comment: 22 pages; greatly shortened, simplified and corrected versio