English

Minimal generating sets of transfer systems for more non-Abelian Groups

Combinatorics 2026-05-08 v1 Algebraic Topology

Abstract

For a finite group GG, NN_\infty operads encode collections of norm maps, and by work of Blumberg--Hill and Rubin their homotopy category is equivalent to the poset of GG--transfer systems on the subgroup lattice of GG. In \cite{ABB+25} the authors defined the \emph{width} w(G)w(G) as the minimal size of a generating set for the complete GG--transfer system and identified it with the number of conjugacy classes of proper meet irreducible subgroups of GG, and the \emph{complexity} c(G)c(G) as the maximum, over all transfer systems TT, of the size of a minimal generating set for TT. We compute w(G)w(G) for the semidihedral groups \SD2n\SD_{2^n} (n4n\ge 4) and the affine Frobenius groups \AGL(1,pn)FpnFpn×\AGL(1,p^n)\cong \mathbb{F}_{p^n}\rtimes \mathbb{F}_{p^n}^\times, extending existing calculations and highlighting how subgroup lattice structure governs equivariant multiplicative complexity. We also compute c(Dpn)c(D_{p^n}) for dihedral groups of order 2pn2p^n with pp an odd prime, establishing c(Dpn)=3n/2+1c(D_{p^n})=\lfloor 3n/2\rfloor+1, and derive the lower bound c(\SD2n)5(n1)/2c(\SD_{2^n})\ge\lfloor 5(n-1)/2\rfloor.

Keywords

Cite

@article{arxiv.2605.04780,
  title  = {Minimal generating sets of transfer systems for more non-Abelian Groups},
  author = {Bheemarasetty Chakravarthy and Surojit Ghosh},
  journal= {arXiv preprint arXiv:2605.04780},
  year   = {2026}
}

Comments

This is a part of Bheemarasetty Chakravarthy's BS-MS thesis. Comments are welcome!