English

Artin transfer patterns on descendant trees of finite p-groups

Group Theory 2015-11-25 v1

Abstract

Based on a thorough theory of the Artin transfer homomorphism TG,H:GH/HT_{G,H}:\,G\to H/H^\prime from a group GG to the abelianization H/HH/H^\prime of a subgroup HGH\le G of finite index n=(G:H)n=(G:H), and its connection with the permutation representation GSnG\to S_n and the monomial representation GHSnG\to H\wr S_n of GG, the Artin pattern G(τ(G),ϰ(G))G\mapsto(\tau(G),\varkappa(G)), which consists of families τ(G)=(H/H)HG\tau(G)=(H/H^\prime)_{H\le G}, resp. ϰ(G)=(ker(TG,H))HG\varkappa(G)=(\ker(T_{G,H}))_{H\le G}, of transfer targets, resp. transfer kernels, is defined for the vertices GTG\in\mathcal{T} of any descendant tree T\mathcal{T} of finite pp-groups. It is endowed with partial order relations τ(π(G))τ(G)\tau(\pi(G))\le\tau(G) and ϰ(π(G))ϰ(G)\varkappa(\pi(G))\ge\varkappa(G), which are compatible with the parent-descendant relation π(G)<G\pi(G)<G of the edges Gπ(G)G\to\pi(G) of the tree T\mathcal{T}. The partial order enables termination criteria for the pp-group generation algorithm which can be used for searching and identifying a finite pp-group GG, whose Artin pattern (τ(G),ϰ(G))(\tau(G),\varkappa(G)) is known completely or at least partially, by constructing the descendant tree with the abelianization G/GG/G^\prime of GG as its root. An appendix summarizes details concerning induced homomorphisms between quotient groups, which play a crucial role in establishing the natural partial order on Artin patterns (τ(G),ϰ(G))(\tau(G),\varkappa(G)) and explaining the stabilization, resp. polarization, of their components in descendant trees T\mathcal{T} of finite pp-groups.

Keywords

Cite

@article{arxiv.1511.07819,
  title  = {Artin transfer patterns on descendant trees of finite p-groups},
  author = {Daniel C. Mayer},
  journal= {arXiv preprint arXiv:1511.07819},
  year   = {2015}
}

Comments

39 pages, 9 figures, dedicated to Professor M. F. Newman