Symmetry Breaking for Representations of Rank One Orthogonal Groups. Workshop on Representations of Lie Groups and their Subgroups (organized by G. Chang). Chalmers University of Technology, Sweden, 19-20 September 2013.

I begin with the general theory of real spherical varieties applied to branching problems, and then explain a method to give a complete classification of breaking symmetry operators between spherical principal series representations of O(n+1,1) and O(n,1). A new feature at integral points will be also discussed. If time allows, I then use the results to determine the breaking symmetry operators between their irreducible composition factors.

© Toshiyuki Kobayashi