English
Related papers

Related papers: Reconstruction Algebras of Type A

200 papers

We give a unified description of twisted forms of classical reductive groups schemes. Such group schemes are constructed from algebraic objects of finite rank, excluding some exceptions of small rank. These objects, augmented odd form…

Group Theory · Mathematics 2026-05-08 Egor Voronetsky

We introduce the notions of relational groupoids and relational convolution algebras. We provide various examples arising from the group algebra of a group $G$ and a given normal subgroup $H$. We also give conditions for the existence of a…

Mathematical Physics · Physics 2021-09-22 Ivan Contreras , Nima Moshayedi , Konstantin Wernli

The relation between representations and positive definite functions is a key concept in harmonic analysis on topological groups. Recently this relation has been studied on topological groupoids. This is the first in a series of papers in…

Operator Algebras · Mathematics 2007-05-23 Massoud Amini , Alireza Medghalchi

We introduce the notion of confined subalgebras in the context of the group von Neumann algebra. We also define Uniformly Recurrent States -- an operator-algebraic analog of Uniformly Recurrent Subgroups. Using this framework, we show that…

Operator Algebras · Mathematics 2026-04-21 Tattwamasi Amrutam , Yongle Jiang

We introduce a general scheme of constructing smooth subalgebras of C$^*$-algebras that are closed under the smooth calculus of self-adjoint elements. We illustrate the scheme with a number of examples.

Operator Algebras · Mathematics 2026-05-12 Shelley Hebert , Slawomir Klimek , Matt McBride

We construct a new family of irreducible modules over any basic classical affine Kac-Moody Lie superalgebra which are induced from modules over the Heisenberg subalgebra. We also obtain irreducible deformations of these modules for the…

Representation Theory · Mathematics 2022-02-10 Luan Pereira Bezerra , Lucas Calixto , Vyacheslav Futorny , Iryna Kashuba

In this paper the authors investigate the structure the restricted Lie algebra cohomology of p-nilpotent Lie algebras with trivial p-power operation. Our study is facilitated by a spectral sequence whose $E_{2}$-term is the tensor product…

Group Theory · Mathematics 2014-08-25 Jon F. Carlson , Daniel K. Nakano

In "A note on generalized Clifford algebras and representations" (Caenepeel, S.; Van Oystaeyen, F., Comm. Algebra 17 (1989) no. 1, 93--102.) generalized Clifford algebras were introduced via Clifford representations; these correspond to…

Rings and Algebras · Mathematics 2009-03-27 Tim Neijens , Fred Van Oystaeyen

We consider the structure of algebra of operators, acting in $n-$fold tensor product space, which are partially transposed on the last term. Using purely algebraical methods we show that this algebra is semi-simple and then, considering its…

Quantum Physics · Physics 2015-06-16 Marek Mozrzymas , Michał Horodecki , Michał Studziński

We investigate the construction and properties of Clifford algebras by a similar manner as our previous construction of the octonions, namely as a twisting of group algebras of Z_2^n by a cocycle. Our approach is more general than the usual…

Quantum Algebra · Mathematics 2007-05-23 H. Albuquerque , S. Majid

Any finite-dimensional commutative (associative) graded algebra with all nonzero homogeneous subspaces one-dimensional is defined by a symmetric coefficient matrix. This algebraic structure gives a basic kind of $A$-graded algebras…

Rings and Algebras · Mathematics 2026-03-23 Yunnan Li , Shi Yu

Recently V.H.L\'opez Sol\'is and I.Shestakov solved an old problem by N.Jacobson on describing of unital alternative algebras containing the $2\times 2$ matrix algebra $M_2$ as a unital subalgebra. Here we give another description of…

Rings and Algebras · Mathematics 2022-12-05 Alexandre Grishkov , Ivan Shestakov

We construct the finite-dimensional continuous complex representations of $\mathrm{SL}_2$ over compact discrete valuation rings of even residual characteristic. We also prove that the complex group algebras of $\mathrm{SL}_2$ over finite…

Representation Theory · Mathematics 2023-08-17 M Hassain

In this paper we analyse the structure of the Cuntz semigroup of certain $C(X)$-algebras, for compact spaces of low dimension, that have no $\mathrm{K}_1$-obstruction in their fibres in a strong sense. The techniques developed yield…

Operator Algebras · Mathematics 2011-01-26 Ramon Antoine , Francesc Perera , Luis Santiago

We generalise the definition of a group algebra so that it makes sense for non-locally compact topological groups, in particular, we require that the representation theory of the group algebra is isomorphic (in the sense of Gelfand-Raikov)…

Operator Algebras · Mathematics 2007-05-23 Hendrik Grundling

In this paper we study rational surface singularities R with star shaped dual graphs, and under very mild assumptions on the self-intersection numbers we give an explicit description of all their special Cohen-Macaulay modules. We do this…

Representation Theory · Mathematics 2023-06-22 Osamu Iyama , Michael Wemyss

We show that a class of algebras is closed under the taking of homomorphic images and direct products if and only if the class consists of all algebras that satisfy a set of (generally simultaneous) equations. For classes of regular…

Group Theory · Mathematics 2022-06-23 Peter M Higgins , Marcel Jackson

We investigate the representations and the structure of Hecke algebras associated to certain finite complex reflection groups. We first describe computational methods for the construction of irreducible representations of these algebras,…

Representation Theory · Mathematics 2019-02-20 Gunter Malle , Jean Michel

We present here two detailed examples of additive categorifications of the cluster algebra structure of a coordinate ring of a maximal unipotent subgroup of a simple Lie group. The first one is of simply-laced type ($A_3$) and relies on an…

Representation Theory · Mathematics 2017-01-27 Laurent Demonet

We study initial algebras of determinantal rings, defined by minors of generic matrices, with respect to their classical generic point. This approach leads to very short proofs for the structural properties of determinantal rings. Moreover,…

Commutative Algebra · Mathematics 2021-05-18 Winfried Bruns , Tim Roemer , Attila Wiebe