Werner Müller is Professor at the Mathematical Institute of the University of Bonn. He is the author of over fifty publications, including articles in Inventiones Mathematicae, Geometric and Functional Analysis, and Communications in Mathematical Physics. His research interests include geometric analysis, scattering theory, analytic theory of automorphic forms, and harmonic analysis on locally symmetric spaces. Sug Woo Shin is Associate Professor of Mathematics at the University of California at Berkeley. His research is centered on number theory, Shimura varieties, Langlands functoriality, trace formula, and automorphic forms. His work has appeared in many journals, including Inventiones Mathematicae, Mathematische Annalen, and the Israel Journal of Mathematics. Nicolas Templier is Associate Professor of Mathematics at Cornell University. His work focuses on number theory, automorphic forms, arithmetic geometry, and mathematical physics. His list of publications include articles in Inventiones Mathematicae, Selecta Mathematica, and the Israel Journal of Mathematics.