English
Related papers

Related papers: Hecke algebras from groups acting on trees and HNN…

200 papers

For every Hecke C*-algebra of right-angled, hyperbolic type, we construct a smooth subalgebra to which traces associated with arbitrary conjugacy classes in the associated Coxeter group extend. We calculate the pairing with K-theory of the…

Operator Algebras · Mathematics 2026-03-25 Piotr Nowak , Sanaz Pooya , Sven Raum , Adam Skalski

Graded Hecke algebras can be constructed geometrically, with constructible sheaves and equivariant cohomology. The input consists of a complex reductive group G (possibly disconnected) and a cuspidal local system on a nilpotent orbit for a…

Algebraic Geometry · Mathematics 2025-01-20 Maarten Solleveld

A geometric extension algebra is an extension algebra of a semi-simple perverse sheaf (allowing shifts), e.g. a push-forward of the constant sheaf under a projective map. Particular nice situations arise for collapsings of homogeneous…

Representation Theory · Mathematics 2015-10-06 Julia Sauter

This paper investigates the connections between buildings and Hecke algebras through the combinatorial study of two algebras spanned by averaging operators on buildings. As a consequence we obtain a geometric and combinatorial description…

Representation Theory · Mathematics 2007-05-23 James Parkinson

In this article we investigate the action of (ramified and unramified) Hecke operators on automorphic forms for the function field of the projective line defined over a finite field and for the group GL_2. We first compute the dimension of…

Number Theory · Mathematics 2024-06-19 Roberto Alvarenga , Nans Bonnel

We analyze the algebraic structures of G--Frobenius algebras which are the algebras associated to global group quotient objects. Here G is any finite group. These algebras turn out to be modules over the Drinfeld double of the group ring…

Algebraic Geometry · Mathematics 2007-05-23 Ralph M. Kaufmann

We investigate the profinite completions of a certain family of groups acting on trees. It turns out that for some of the groups considered, the completions coincide with the closures of the groups in the full group of tree automorphisms.…

Group Theory · Mathematics 2007-05-23 Ekaterina Pervova

This paper is an expanded and updated version of the preprint arXiv:math/0406499. It includes a more detailed description of the basics of the theory of Cherednik and Hecke algebras of varieties started in arXiv:math/0406499, as well as a…

Quantum Algebra · Mathematics 2017-03-21 Pavel Etingof

The main result of this paper shows that, over large enough fields of characteristic different from $2$, the alternating Hecke algebras are $\mathbb{Z}$-graded algebras that are isomorphic to fixed-point subalgebras of the quiver Hecke…

Representation Theory · Mathematics 2016-08-08 Clinton Boys , Andrew Mathas

In this paper we study homological properties of modules over an affine Hecke algebra H. In particular we prove a comparison result for higher extensions of tempered modules when passing to the Schwartz algebra S, a certain topological…

Representation Theory · Mathematics 2009-05-20 Eric Opdam , Maarten Solleveld

Hecke algebras are usually defined algebraically, via generators and relations. We give a new algebro-geometric construction of affine and double-affine Hecke algebras (the former is known as the Iwahori-Hecke algebra, and the latter was…

alg-geom · Mathematics 2008-02-03 Victor Ginzburg , Mikhail Kapranov , Eric Vasserot

Aiming for a revival of the theory of crystallographic complex reflection groups, we compute (minimal) Coxeter-like reflection presentations for the infinite families of those non-genuine groups which satisfy Steinberg's fixed point…

Group Theory · Mathematics 2025-10-10 Davide Dal Martello

We investigate deformations of skew group algebras arising from the action of the symmetric group on polynomial rings over fields of arbitrary characteristic. Over the real or complex numbers, Lusztig's graded affine Hecke algebra and…

Representation Theory · Mathematics 2022-05-12 Naomi Krawzik , Anne Shepler

This thesis is devoted to the study of the interactions existing between the algebraic structure of locally compact groups and the properties of their continuous unitary representations, with a special emphasis on the Type I groups. On the…

Representation Theory · Mathematics 2023-06-08 Lancelot Semal

Automorphism groups of locally finite trees provide a large class of examples of simple totally disconnected locally compact groups. It is desirable to understand the connections between the global and local structure of such a group.…

Group Theory · Mathematics 2012-01-19 Pierre-Emmanuel Caprace , Tom De Medts

We introduce the spin Hecke algebra, which is a q-deformation of the spin symmetric group algebra, and its affine generalization. We establish an algebra isomorphism which relates our spin (affine) Hecke algebras to the (affine)…

Representation Theory · Mathematics 2011-11-09 Weiqiang Wang

We study Hecke operators associated with curves over a non-archimedean local field $K$ and over the rings $O/{\mathfrak m}^N$, where $O\subset K$ is the ring of integers. Our main result is commutativity of a certain "small" local Hecke…

Number Theory · Mathematics 2025-07-31 Alexander Braverman , David Kazhdan , Alexander Polishchuk , Ka Fai Wong

The current article is a short survey on the theory of Hecke algebras, and in particular Kazhdan-Lusztig theory, and on the theory of symplectic reflection algebras, and in particular rational Cherednik algebras. The emphasis is on the…

Representation Theory · Mathematics 2014-01-21 Maria Chlouveraki

We address the problem to characterise closed type I subgroups of the automorphism group of a tree. Even in the well-studied case of Burger-Mozes' universal groups, non-type I criteria were unknown. We prove that a huge class of groups…

Group Theory · Mathematics 2016-11-30 Cyril Houdayer , Sven Raum

Let G be a split Kac-Moody group over a non-archimedean local field. We define a completion of the Iwahori-Hecke algebra of G. We determine its center and prove that it is isomorphic to the spherical Hecke algebra of G using the Satake…

Representation Theory · Mathematics 2023-09-15 Ramla Abdellatif , Auguste Hébert