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We calculate the extension groups between simple modules of pro-$p$-Iwahori Hecke algebras.

Representation Theory · Mathematics 2017-05-03 Noriyuki Abe

We prove a recursive formula for the exterior and symmetric powers of modules for a cyclic 2-group. This makes computation straightforward. Previously, a complete description was only known for cyclic groups of prime order.

Representation Theory · Mathematics 2015-10-09 Frank Himstedt , Peter Symonds

Algebraic deformations of modules over a ring are considered. The resulting theory closely resembles Gerstenhaber's deformation theory of associative algebras.

Commutative Algebra · Mathematics 2007-05-23 Donald Yau

We introduce cell modules for the tabular algebras defined in a previous work (math.QA/0107230); these modules are analogous to the representations arising from left Kazhdan--Lusztig cells. The standard modules of the title are constructed…

Quantum Algebra · Mathematics 2007-05-23 R. M. Green

We extend a conjecture of Kimberley-Robertson on the abelianizations of certain square complex groups.

Group Theory · Mathematics 2007-05-23 Diego Rattaggi

In this paper, we give a characterization of Coxeter group representations of Lusztig's a-function value 1, then determine all the irreducible such representations for certain simply laced Coxeter groups.

Representation Theory · Mathematics 2026-03-23 Hongsheng Hu

In this paper we prove parts of a conjecture of Herzog giving lower bounds on the rank of the free modules appearing in the linear strand of a graded $k$-th syzygy module over the polynomial ring. If in addition the module is…

Commutative Algebra · Mathematics 2021-05-18 Tim Roemer

This paper surveys, and in some cases generalises, many of the recent results on homomorphisms and the higher Ext groups for q-Schur algebras and for the Hecke algebra of type A. We review various results giving isomorphisms between Ext…

Representation Theory · Mathematics 2007-05-23 Anton Cox , Alison Parker

We give the expression of the metric derived from Lie groups. For the metric derived from classical Lie groups such as the unitary group, the orthogonal group and the symplectic group, we conjecture that the metric becomes the Einstein…

Differential Geometry · Mathematics 2017-02-27 Kazuyasu Shigemoto

The aim of this work is to prove a conjecture related to the Combinatorial Invariance Conjecture of Kazhdan-Lusztig polynomials, in the parabolic setting, for lower intervals in every arbitrary Coxeter group. This result improves and…

Combinatorics · Mathematics 2018-07-09 Mario Marietti

We generalize a cohomological construction of representations due to Lusztig from the hyperspecial case to arbitrary parahoric subgroups of a reductive group over a local field, which splits over an unramified extension. We compute the…

Representation Theory · Mathematics 2019-03-15 Charlotte Chan , Alexander B. Ivanov

We obtain explicit branching rules for graded cell modules and graded simple modules over the endomorphism algebra of a Bott-Samelson bimodule. These rules allow us to categorify a well-known recursive formula for Kazhdan-Lusztig…

Representation Theory · Mathematics 2015-07-17 David Plaza

Let $A,A^*$ be the generators of the $q-$Onsager algebra. Analogues of Lusztig's $r-th$ higher order relations are proposed. In a first part, based on the properties of tridiagonal pairs of $q-$Racah type which satisfy the defining…

Mathematical Physics · Physics 2015-06-18 P. Baseilhac , T. T. Vu

In this paper we study higher Deligne--Lusztig representations of reductive groups over finite quotients of discrete valuation rings. At even levels, we show that these geometrically constructed representations coincide with certain induced…

Representation Theory · Mathematics 2016-04-07 Zhe Chen , Alexander Stasinski

We prove Lusztig's conjectures P1-P15 for hyperbolic Coxeter groups of rank 3. Our proof enables us to give a description of the a-function and Kazhdan-Lusztig cells for these Coxeter groups.

Representation Theory · Mathematics 2020-10-14 Jianwei Gao , Xun Xie

We prove Lusztig's conjectures ${\bf P1}$-${\bf P15}$ for the affine Weyl group of type $\tilde{C}_2$ for all choices of positive weight function. Our approach to computing Lusztig's $\mathbf{a}$-function is based on the notion of a…

Representation Theory · Mathematics 2018-11-19 J. Guilhot , J. Parkinson

We prove the strong Atiyah conjecture for right-angled Artin groups and right-angled Coxeter groups. More generally, we prove it for groups which are certain finite extensions or elementary amenable extensions of such groups.

Geometric Topology · Mathematics 2012-10-12 Peter Linnell , Boris Okun , Thomas Schick

We prove a tamely ramified version of the Kazhdan-Lusztig equivalence using factorization algebras. More precisely, we establish an equivalence between the DG category of Iwahori-integrable affine Lie algebra representations and the DG…

Representation Theory · Mathematics 2021-11-30 Lin Chen , Yuchen Fu

A general method for constructing logarithmic modules in vertex operator algebra theory is presented. By utilizing this approach, we give explicit vertex operator construction of certain indecomposable and logarithmic modules for the…

Quantum Algebra · Mathematics 2014-11-18 Drazen Adamovic , Antun Milas

We describe a logarithmic tensor product theory for certain module categories for a ``conformal vertex algebra.'' In this theory, which is a natural, although intricate, generalization of earlier work of Huang and Lepowsky, we do not…

Quantum Algebra · Mathematics 2008-11-26 Yi-Zhi Huang , James Lepowsky , Lin Zhang