6 papers
Stability of Multiplicities in Symmetry Breaking: The sl_2 Case
Toshiyuki Kobayashi
This expository paper explains, in the case of , the ideas introduced in the preprints (arXiv:2509.17007, 2604.22262), which develop a new framework for the study…
Stability of Branching Multiplicities for Orthogonal Gelfand Pairs
Toshiyuki Kobayashi
We propose a structural framework for branching multiplicities in representation theory, emphasizing their behavior under variation of infinitesimal characters. For the orthogonal…
How does the restriction of representations change under translations? A story for the general linear groups and the unitary groups
Toshiyuki Kobayashi, Birgit Speh
We present a new approach to symmetry breaking for pairs of real forms of . Translation functors are powerful tools for studying families…
Harish-Chandra's admissibility theorem and beyond
Toshiyuki Kobayashi
This article is a record of the lecture at the centennial conference for Harish-Chandra. The admissibility theorem of Harish-Chandra concerns the restrictions of irreducible repres…
Translation functors, branching problems, and applications to the restriction of coherent cohomology of Shimura varieties
Michael Harris, Toshiyuki Kobayashi, Birgit Speh
We study properties of the restriction of discrete series representations of to and the corresponding symmetry breaking operators in $\operatorname{Hom}_{…
Proper Actions and Representation Theory
Toshiyuki Kobayashi
This exposition presents recent developments on proper actions, highlighting their connections to representation theory. It begins with geometric aspects, including criteria for th…