English

Representations of categories of G-maps

Representation Theory 2019-05-14 v4 Algebraic Topology Combinatorics Group Theory

Abstract

We study representations of wreath product analogues of categories of finite sets. This includes the category of finite sets and injections (studied by Church, Ellenberg, and Farb) and the opposite of the category of finite sets and surjections (studied by the authors in previous work). We prove noetherian properties for the injective version when the group in question is polycyclic-by-finite and use it to deduce general twisted homological stability results for such wreath products and indicate some applications to representation stability. We introduce a new class of formal languages (quasi-ordered languages) and use them to deduce strong rationality properties of Hilbert series of representations for the surjective version when the group is finite.

Keywords

Cite

@article{arxiv.1410.6054,
  title  = {Representations of categories of G-maps},
  author = {Steven V Sam and Andrew Snowden},
  journal= {arXiv preprint arXiv:1410.6054},
  year   = {2019}
}

Comments

27 pages, split off from arXiv:1409.1670v1; v2: added Section 5.2 on wreath product version of Murnaghan's stability theorem; v3: significant rewrite; v4: corrected some proofs