Browsing 2025 by MSC "20"

Now showing items 1-3 of 3

    • On the Complexity of Epimorphism Testing with Virtually Abelian Targets 

      [OWP-2025-01] Elder, Murray; Shen, Jerry; Weiss, Armin (Mathematisches Forschungsinstitut Oberwolfach, 2025-01)
      Friedl and Löh (2021, Confl. Math.) prove that testing whether or not there is an epimorphism from a finitely presented group to the direct product of an abelian and a finite group, or to a virtually cyclic group, is ...

    • Parabolic Normalizers in Finite Coxeter Groups as Subdirect Products 

      [OWP-2025-10] Douglass, J. Matthew; Pfeiffer, Götz; Röhrle, Gerhard (Mathematisches Forschungsinstitut Oberwolfach, 2025-09)
      We revisit the structure of the normalizer $N_W(P)$ of a parabolic subgroup $P$ in a finite Coxeter group $W$, originally described by Howlett. Building on Howlett's Lemma, which provides canonical complements for reflection ...

    • The $q$-Deformed Random-to-Random Family in the Hecke Algebra 

      [OWP-2025-12] Brauner, Sarah; Commins, Patricia; Grinberg, Darij; Saliola, Franco (Mathematisches Forschungsinstitut Oberwolfach, 2025-11)
      We generalize Reiner-Saliola-Welker's well-known but mysterious family of $k$-random-to-random shuffles from Markov chains on symmetric groups to Markov chains on the Type-$A$ Iwahori-Hecke algebras. We prove that the ...