Results 51 to 60 of about 2,366 (219)
Signed Projective Cubes, a Homomorphism Point of View
ABSTRACT The (signed) projective cubes, as a special class of graphs closely related to the hypercubes, are on the crossroad of geometry, algebra, discrete mathematics and linear algebra. Defined as Cayley graphs on binary groups, they represent basic linear dependencies.
Meirun Chen +2 more
wiley +1 more source
On excess in finite Coxeter groups [PDF]
For a finite Coxeter group $W$ and $w$ an element of $W$ the `excess' of $w$ is defined to be $e(w) = \min\{\ell(x) + \ell(y) - \ell(w) \; | \; w=xy, \; x^2 = y^2 = 1\}$ where $\ell$ is the length function on $W$. Here we investigate the behaviour of $e(w)$, and a related concept reflection excess, when restricted to standard parabolic subgroups of $W$.
Hart, Sarah B. +1 more
openaire +4 more sources
Sensitivity and Hamming Graphs
ABSTRACT For any m ≥ 3 we show that the Hamming graph H ( n , m ) admits an imbalanced partition into m sets, each inducing a subgraph of low maximum degree. This improves previous results by Tandya and by Potechin and Tsang, and disproves the Strong m‐ary Sensitivity Conjecture of Asensio, García‐Marco, and Knauer.
Sara Asensio +3 more
wiley +1 more source
On conjugacy separability of some Coxeter groups and parabolic-preserving automorphisms [PDF]
We prove that even Coxeter groups, whose Coxeter diagrams contain no (4, 4, 2) triangles, are conjugacy separable. In particular, this applies to all right-angled Coxeter groups or word hyperbolic even Coxeter groups. For an arbitrary Coxeter group W, we
Caprace, Pierre-Emmanuel +1 more
core
Peak algebras, paths in the Bruhat graph and Kazhdan-Lusztig polynomials [PDF]
We obtain a nonrecursive combinatorial formula for the Kazhdan-Lusztig polynomials which holds in complete generality and which is simpler and more explicit than any existing one, and which cannot be linearly simplified. Our proof uses a new basis of the
Francesco Brenti, Fabrizio Caselli
doaj +1 more source
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
openaire +4 more sources
Proper 3‐realizability and second cohomology of groups on two generators of finite order
Abstract Given an (infinite) finitely generated group G$G$, its first cohomology group H1(G;ZG)$H^1(G;{\mathbb {Z}}G)$ is free abelian and “counts” the number of ends of G$G$ which equals 1+rank(H1(G;ZG))$1 + rank (H^1(G;{\mathbb {Z}}G))$. The question whether or not for every finitely presented group G$G$ its second cohomology group H2(G;ZG)$H^2(G ...
Francisco F. Lasheras, R. Roy
wiley +1 more source
Hecke group algebras as degenerate affine Hecke algebras [PDF]
The Hecke group algebra $\operatorname{H} \mathring{W}$ of a finite Coxeter group $\mathring{W}$, as introduced by the first and last author, is obtained from $\mathring{W}$ by gluing appropriately its $0$-Hecke algebra and its group algebra.
Florent Hivert +2 more
doaj +1 more source
Coxeter quotients of the automorphism group of a Coxeter group
We show that for a large class $\mathcal{W}$ of Coxeter groups the following holds: Given a group $W_Γ$ in $\mathcal{W}$, the automorphism group ${\rm Aut}(W_Γ)$ virtually surjects onto some infinite Coxeter group. In particular, the group ${\rm Aut}(W_Γ)$ is virtually indicable and therefore does not have Kazhdan's property (T).
openaire +2 more sources
Generalised spin Calogero–Moser systems from Cherednik algebras
Abstract Integrable spin Calogero–Moser type systems with non‐symmetric configurations of the singularities of the potential appeared in the work of Chalykh, Goncharenko and Veselov in 1999. We obtain various generalisations of these examples by making use of the representation theory of Cherednik algebras.
Misha Feigin +2 more
wiley +1 more source

