This week's speaker is Prof. Johannes Kellendonk from Lyon.
Room 39C. 174, 3.30pm Thursday 12 November.
Title: C*-algebraic approach to topological phases
Abstract: Topological insulators are physical materials which behave like insulators in the bulk but have currents on their boundary which can not be destroyed by disorder. Theoretical analysis suggests that there are 10 universality classes of symmetries such an insulator can have. It is a challenge to understand that properly.
We look at the bulk theory and more precisely at the C-algebra of observables of the bulk theory and show how the symmetries can be implemented. The ten universality classes are then described by van Daele's K-theory for graded real or complex C-algebras.