Geometric Arthur parameters

Abstract: Arthur proposed a description of automorphic forms in terms of tempered automorphic forms for centralizers of SL2 homomorphisms. I will explain a point of view on the Arthur parameterization in the setting of function fields coming from relative Langlands duality, emphasizing the role of $shearing$ (the symmetry of the derived category of graded vector spaces which simultaneously shifts weights and cohomological degrees). Shearing helps account for a deficit of Tannakian formalism in the derived context - there are more eigenvalues for tensor actions than one might expect. The talk reports on joint work with Yiannis Sakellaridis and Akshay Venkatesh.

number theory

Audience: researchers in the topic

BC-MIT number theory seminar