Abhishek
Saha
School of
Mathematical Sciences
Queen Mary University of London
Title: Some analytic aspects of automorphic forms
and L-functions
Abstract: The eigenfunctions (of the Laplacian) on
various geometric spaces constitute a class of
mathematical objects of fundamental importance. From
the point of view of quantum mechanics, the
eigenfunctions correspond to particles moving with a
certain energy, which leads naturally to questions
motivated by subfields of physics. For example, one
also has the so-called sup-norm problem, which asks
how high the peaks of an eigenfunctions can be.
In this talk, I
will give a gentle introduction to some of these
problems in a setting where number theory plays a key
role. In the special case when the manifold is a
surface of constant negative structure, and is
constructed from "quaternion algebras", a famous
result of Iwaniec and Sarnak improves upon the trivial
bound for the sup-norm using number-theoretic
techniques. I will explain this result, and then talk
about recent progress on an analogous question where
the underlying surface is itself allowed to vary.
There are also many interesting connections between
these questions and deep open conjectures in number
theory such as the Grand Riemann hypothesis, which I
will attempt to explain.