Patrick Dorey (Durham):
Intertwiners and the Geometry of Root Systems
This talk will describe how certain sets of integers
arising in the study of lattice models on cylinders can be given
a geometrical interpretation in terms of root systems and the
Coxeter element. This establishes their positivity in a uniform
way, and also elucidates connections with results of Kostant
concerning the finite subgroups of su(2).