English

Euler-Poincar\'{e} formulae for positive depth Bernstein projectors

Representation Theory 2020-06-29 v1

Abstract

Work of Bezrukavnikov-Kazhdan-Varshavsky uses an equivariant system of trivial idempotents of Moy-Prasad groups to obtain an Euler-Poincar\'{e} formula for the r-depth Bernstein projector. Barbasch-Ciubotaru-Moy use depth-zero cuspidal representations of parahoric subgroups to decompose the Euler-Poincar\'{e} presentation of the depth-zero projector. For positive depth rr, we establish a decomposition of the Euler-Poincar\'{e} presentation of the r-depth Bernstein projector based on a notion of associate classes of cuspidal pairs for Moy-Prasad quotients. We apply these new Euler-Poincar\'{e} presentations to the obtain decompositions of the resolutions of Schneider-Stuhler and Bestvina-Savin.

Cite

@article{arxiv.2006.14648,
  title  = {Euler-Poincar\'{e} formulae for positive depth Bernstein projectors},
  author = {Allen Moy and Gordan Savin},
  journal= {arXiv preprint arXiv:2006.14648},
  year   = {2020}
}

Comments

36 pages, 2 figures

R2 v1 2026-06-23T16:38:07.180Z