This project supports research in several areas of algebra and number theory. One principal investigator will study the analytic and geometric construction of lattices of Lie groups. Another principal investigator will investigate analytic and number theoretic questions with particular emphasis on L-functions of automorphic forms. The third principal investigator will develop invariant theory in order to apply it to the study of explicit structure of infinite dimensional representations of semisimple Lie groups. The postdoctoral associate will study several questions about representations of groups over local fields with a view toward applying these results to L-functions and automorphic forms. This is a broad research program centered around the theory of Lie groups. The applications will be in geometry, number theory and physics.