Peter
Humphries
Department
of Mathematics
University of Virginia
Title: Hybrid subconvex bounds for self-dual GL(3)
L-functions via spectral reciprocity
Abstract: We discuss the subconvexity problem in the
setting of GL(3) x GL(2) x GL(1) Rankin-Selberg
L-functions involving a fixed GL(3) automorphic form,
a GL(2) automorphic form, and a twist by a primitive
Dirichlet character. In favourable situations, namely
when the GL(3) form is self-dual, the central value of
this L-function is non-negative. In this setting, we
show how one can obtain subconvex bounds for this
central L-value in the GL(2)- and GL(1)-aspects by
extending a first moment method pioneered by Conrey
and Iwaniec and later by Xiaoqing Li. We reformulate
their approaches in the language of spectral
reciprocity: exact identities for moments of
L-functions in terms of other moments of L-functions.
This is joint work with Soumendra Ganguly, Yongxiao
Lin, and Ramon Nunes.