3 papers
math.GR2025
Parabolic Normalizers in Finite Coxeter Groups as Subdirect Products
J. Matthew Douglass, Götz Pfeiffer, Gerhard Roehrle
We revisit the structure of the normalizer of a parabolic subgroup in a finite Coxeter group , originally described by Howlett. Building on Howlett's Lemma, which p…
math.RT2018
On the Invariants of the Cohomology of Complements of Coxeter Arrangements
J. Matthew Douglass, Goetz Pfeiffer, Gerhard Roehrle
We refine Brieskorn's study of the cohomology of the complement of the reflection arrangement of a finite Coxeter group . As a result we complete the verification of a conjectur…
math.RT2007
The homology of the Steinberg variety and Weyl group coinvariants
J. Matthew Douglass, Gerhard Roehrle
Let G be a complex, connected, reductive algebraic group with Weyl group W and Steinberg variety Z. We show that the graded Borel-Moore homology of Z is isomorphic to the smash pro…