English

Around evaluations of biset functors

Representation Theory 2018-07-24 v3 Group Theory

Abstract

For a non-vanishing group, we show that the evaluation functor induces an equivalence between the category of modules over the double Burnside algebra and a certain category of biset functors. Using this equivalence, we deduce that over a field of characteristic zero, the double Burnside algebra of a non-vanishing group is a quasi-hereditary algebra. We also show that the double Burnside algebra over a field is self-injective if and only if it is semisimple.

Keywords

Cite

@article{arxiv.1511.03314,
  title  = {Around evaluations of biset functors},
  author = {Baptiste Rognerud},
  journal= {arXiv preprint arXiv:1511.03314},
  year   = {2018}
}

Comments

v2: there is now a part on the exact Borel subalgebras. I also gave a proof '\`a la Bouc-Th\'evenaz'of Barker's Theorem on the semi-simplicity of the category of biset functors. v3: accepted for publication in Annales de l'institut Fourier

R2 v1 2026-06-22T11:42:02.457Z