ANALYSIS AND GROUP ACTIONS ON TREES AND BUILDINGS
Special semester at Rutgers, Spring 2006
Organized by Lisa Carbone, Donald Cartwright and George Willis

In recent years there have been a wealth of new results revealing the emerging role of group actions on trees and buildings in the study of infinite dimensional algebra, discrete subgroups of Lie groups, automorphic forms and arithmetic properties of groups, Kac-Moody algebras and groups in physics, low dimensional topology and the construction of expanders. The theory of group actions on trees and buildings is a powerful combinatorial tool and one of the few known methods that allows us to link these diverse topics.

In Spring 2006, our collaborative research group focussed on group actions on trees and buildings with applications to a range of topics involving analysis, number theory, geometry, combinatorics, algebra and physics.

Our program was held in parallel with the special year at the Institute for Advanced Study at Princeton in the academic year 2005/6, on Lie Groups, Representations and Discrete Mathematics , led by Alex Lubotzky.

We were funded in part by grants from the National Science Foundation, the Australian Research Council and Rutgers / DIMACS.

LONG TERM VISITORS
Udo Baumgartner, Univertsity of Newcastle, Australia
Donald Cartwright, Sydney University, Australia
Hisham Sati, University of Adelaide. Australia
Zoran Sunik, Texas A&M Univertsity
George Willis, Univertsity of Newcastle, Australia

SHORT TERM VISITORS
Mikhail Ershov, Institute for Advanced Studies
Avinoam Mann, Hebrew University of Jerusalem
Matthias Neufang, Carleton University, Canada
Jacqui Rammage, Univertsity of Newcastle, Australia
Alireza Salehi Golsefidy, Yale University
Aner Shalev, Hebrew University of Jerusalem
Alain Valette, Universite de Neuchatel, Switzerland

PARTICIPATING GRADUATE STUDENTS
Corina Calinescu, Rutgers University
Dennis Clark, University of Michigan
Leigh Cobbs, Rutgers University
Alexander Conway, Rutgers University
Diego Penta, Rutgers University
Anne Thomas, University of Chicago