Results 1 to 10 of about 49 (39)

Symmetry of Narayana Numbers and Rowvacuation of Root Posets

open access: yesForum of Mathematics, Sigma, 2021
For a Weyl group W of rank r, the W-Catalan number is the number of antichains of the poset of positive roots, and the W-Narayana numbers refine the W-Catalan number by keeping track of the cardinalities of these antichains.
Colin Defant, Sam Hopkins
doaj   +1 more source

On the systole growth in congruence quaternionic hyperbolic manifolds

open access: yesBulletin of the London Mathematical Society, Volume 54, Issue 4, Page 1265-1281, August 2022., 2022
Abstract We provide an explicit lower bound for the systole in principal congruence covers of compact quaternionic hyperbolic manifolds. We also prove the optimality of this lower bound.
Vincent Emery   +2 more
wiley   +1 more source

Intersecting principal Bruhat ideals and grades of simple modules [PDF]

open access: yes, 2022
We prove that the grades of simple modules indexed by boolean permutations, over the incidence algebra of the symmetric group with respect to the Bruhat order, are given by Lusztig's \(\mathbf{a}\)-function. Our arguments are combinatorial, and include a
Tenner, Bridget Eileen   +6 more
core   +1 more source

Equivariant perverse sheaves on Coxeter arrangements and buildings [PDF]

open access: yesÉpijournal de Géométrie Algébrique, 2019
When $W$ is a finite Coxeter group acting by its reflection representation on $E$, we describe the category ${\mathsf{Perv}}_W(E_{\mathbb C}, {\mathcal{H}}_{\mathbb C})$ of $W$-equivariant perverse sheaves on $E_{\mathbb C}$, smooth with respect to the ...
Martin H. Weissman
doaj   +1 more source

Harmonic differential forms for pseudo-reflection groups II. Bi-degree bounds [PDF]

open access: yes, 2023
This paper studies three results that describe the structure of the super-coinvariant algebra of pseudo-reflection groups over a field of characteristic \(0\).
Wallach, Nolan R., Swanson, Joshua P.
core   +1 more source

Generalized associahedra via brick polytopes [PDF]

open access: yesDiscrete Mathematics & Theoretical Computer Science, 2012
We generalize the brick polytope of V. Pilaud and F. Santos to spherical subword complexes for finite Coxeter groups. This construction provides polytopal realizations for a certain class of subword complexes containing all cluster complexes of finite ...
Vincent Pilaud, Christian Stump
doaj   +1 more source

A sheep in wolf’s clothing: from group theory to a novel antiviral strategy

open access: yes, 2022
The recent pandemic has led to a particular interest in mathematical and computational virology. I have previously given an introduction to virus structure and assembly, in particular the group theory aspect of structure and the modelling aspects of ...
Dechant, Pierre-Philippe
core   +3 more sources

Homological stability for Artin monoids

open access: yesProceedings of the London Mathematical Society, Volume 121, Issue 3, Page 537-583, September 2020., 2020
Abstract We prove that certain sequences of Artin monoids containing the braid monoid as a submonoid satisfy homological stability. When the K(π,1) conjecture holds for the associated family of Artin groups, this establishes homological stability for these groups.
Rachael Boyd
wiley   +1 more source

Generic Newton points and the Newton poset in Iwahori-double cosets

open access: yesForum of Mathematics, Sigma, 2020
We consider the Newton stratification on Iwahori-double cosets in the loop group of a reductive group. We describe a group-theoretic condition on the generic Newton point, called cordiality, under which the Newton poset (that is, the index set for non ...
Elizabeth Milićević, Eva Viehmann
doaj   +1 more source

Commuting involution graphs for [(A)\tilde]n [PDF]

open access: yes, 2006
In this article we consider the commuting graphs of involution conjugacy classes in the affine Weyl group A~n. We show that where the graph is connected the diameter is at most 6.
Hart, Sarah, Hart, Sarah B.
core   +1 more source

Home - About - Disclaimer - Privacy