Steve Lester: Equidistribution of mass for modular forms

In this talk I will discuss a holomorphic analog of the Quantum Unique Ergodicity conjecture of Rudnick and Sarnak in the context of modular forms for $SL_2(\mathbb Z)$. In particular, I will describe the work of Holowinsky and Soudararajan who showed that the $L^2$ mass of holomorphic Hecke cusp forms equidistributes with respect to hyperbolic measure in the limit as the weight tends to infinity.