English
Related papers

Related papers: Quasidiagonal Representations of Nilpotent Groups

200 papers

Solutions which are quasimodular forms to a second order differential equation attached to a triangular group are explicitly described in terms of certain orthogonal polynomials.

Number Theory · Mathematics 2007-05-23 Masanobu Kaneko , Masao Koike

For a finite group $G$, let $p(G)$ denote the minimal degree of a faithful permutation representation of $G$. The minimal degree of a faithful representation of $G$ by quasi-permutation matrices over the fields $\mathbb{C}$ and $\mathbb{Q}$…

Representation Theory · Mathematics 2021-06-25 Soham Swadhin Pradhan , B. Sury

Given a group G, we construct, in a canonical way, an inverse semigroup S(G) associated to G. The actions of S(G) are shown to be in one-to-one correspondence with the partial actions of G, both in the case of actions on a set, and that of…

funct-an · Mathematics 2008-02-03 Ruy Exel

With this work we initiate a study of the representations of a unipotent group over a field of characteristic zero from the modular point of view. Let $G$ be such a group. The stack of all representations of a fixed finite dimension $n$ is…

Algebraic Geometry · Mathematics 2010-02-26 Ishai Dan-Cohen

For a locally compact group $G$, we show that it is possible to present the class of continuous unitary representations of $G$ as an elementary class of metric structures, in the sense of continuous logic. More precisely, we show how…

Classical Analysis and ODEs · Mathematics 2021-11-05 Itaï Ben Yaacov , Isaac Goldbring

We study finite-dimensional nonassociative algebras. We prove the implicit function theorem for such algebras. This allows us to establish a correspondence between such algebras and quasigroups, in the spirit of classical correspondence…

Rings and Algebras · Mathematics 2022-08-23 Yuri Bahturin , Alexander Olshanskii

It is first shown that the nilpotent or the solvable approximation of an almost-Riemannian structure at a singular point is always a linear almost-Riemannian structure on a Lie group or a homogeneous space. The generic properties of…

Optimization and Control · Mathematics 2022-04-25 Yacine Chitour , Philippe Jouan , Ronald Manríquez

Let S be a subsemigroup of an abelian torsion-free group G. If S is a positive cone of G, then all C*-algebras generated by faithful isometrical non-unitary representations of S are canonically isomorphic. Proved by Murphy, this statement…

Operator Algebras · Mathematics 2012-12-04 M. A. Aukhadiev , V. H. Tepoyan

We consider numerical semigroups associated with normal weighted homogeneous surface singularities with rational homology sphere links. We say that a semigroup is representable if it can be realized in this way. In this article, we study…

Algebraic Geometry · Mathematics 2026-01-21 Zsolt Baja , Tamás László

We develop a semigroup approach to representation theory for pro-Lie groups satisfying suitable amenability conditions. As an application of our approach, we establish a one-to-one correspondence between equivalence classes of unitary…

Representation Theory · Mathematics 2016-06-07 Daniel Beltita , Amel Zergane

We study the minimal unitary representations of non-compact groups and supergroups obtained by quantization of their geometric realizations as quasi-conformal groups and supergroups. The quasi-conformal groups G leave generalized…

High Energy Physics - Theory · Physics 2011-02-09 Murat Gunaydin , Oleksandr Pavlyk

We define a `nice representation' of a finitely presented group G as being a non-degenerate essentially surjective simplicial map f from a `nice' space X into a 3-complex associated to a presentation of G, with a strong control over the…

Geometric Topology · Mathematics 2016-03-22 Daniele Ettore Otera , Valentin Poenaru

Representations of Quantum Groups U_q (g_n), g_n any semi simple Lie algebra of rank n, are constructed from arbitrary representations of rank n-1 quantum groups for q a root of unity. Representations which have the maximal dimension and…

High Energy Physics - Theory · Physics 2009-10-22 Wolfgang A. Schnizer

In this paper, we investigate nilpotent and unimodular solvable Lie groups that admit quasi-Einstein metrics $(M,g,X)$ with $X$ a left-invariant vector field, which we call totally left-invariant quasi-Einstein metrics. We give a complete…

Differential Geometry · Mathematics 2025-09-30 Nazia Valiyakath

In this paper, we describe the relationship between the quasi-component q(G) of a (perfectly) minimal pseudocompact abelian group G and the quasi-component q(\widetilde G) of its completion. Specifically, we characterize the pairs (C,A) of…

General Topology · Mathematics 2012-03-19 D. Dikranjan , Gábor Lukács

The orthogonal groups are a series of simple Lie groups associated to symmetric bilinear forms. There is no analogous series associated to symmetric trilinear forms. We introduce an infinite dimensional group-like object that can be viewed…

Representation Theory · Mathematics 2021-09-27 Andrew Snowden

We provide an explicit construction for a complete set of orthogonal primitive idempotents of finite group algebras over nilpotent groups. Furthermore, we give a complete set of matrix units in each simple epimorphic image of a finite group…

Representation Theory · Mathematics 2013-02-19 Inneke Van Gelder , Gabriela Olteanu

In this paper, we construct certain unipotent representations for the real orthogonal group and the metaplectic group in the sense of Vogan. Our construction is based on quantum induction which involves the compositions of even number of…

Representation Theory · Mathematics 2022-01-03 Hongyu He

In this note we start the study of whether the reduced C*-algebra of an inverse semigroup is quasi-diagonal, making explicit use of the inner structure of this class of semigroups in order to produce quasi-diagonal approximations. Given a…

Operator Algebras · Mathematics 2022-08-23 Diego Martínez

We introduce the decomposition rank, a notion of covering dimension for nuclear C^*-algebras. The decomposition rank generalizes ordinary covering dimension and has nice permanence properties; in particular, it behaves well with respect to…

Operator Algebras · Mathematics 2007-05-23 Eberhard Kirchberg , Wilhelm Winter