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We introduce the notion of non commutative truncated polynomial extension of an algebra A. We study two families of these extensions. For the first one we obtain a complete classification and for the second one, which we call upper…

Rings and Algebras · Mathematics 2011-11-28 Jorge A. Guccione , Juan J. Guccione , Christian Valqui

In this article, we apply the approach of relative algebraic geometry towards analytic geometry to the category of bornological and Ind-Banach spaces (non-Archimedean or not). We are able to recast the theory of Grosse-Kl\"onne dagger…

Algebraic Geometry · Mathematics 2022-10-12 Federico Bambozzi , Oren Ben-Bassat

We revisit G. Elek's notion of amenable representation type, where algebras are characterised by every indecomposable module being "almost" the direct sum of modules of bounded dimension. We give a new proof of his result that string…

Representation Theory · Mathematics 2022-08-19 Sebastian Eckert

We describe a natural structure of an abelian intertwining algebra (in the sense of Dong and Lepowsky) on the direct sum of the untwisted vertex operator algebra constructed {}from the Leech lattice and its (unique) irreducible twisted…

High Energy Physics - Theory · Physics 2008-02-03 Yi-Zhi Huang

For any injective von Neumann algebra R and any discrete, countable group G, which acts by *-automorphisms on R, we construct an idempotent mapping of an ultra-weakly dense subspace of B(H) onto the reducerd crossed product von Neumann…

Operator Algebras · Mathematics 2020-06-15 Erik Christensen

Let $A$ be a unital associative algebra over a field $k$. All unital associative algebras containing $A$ as a subalgebra of a given codimension $\mathfrak{c}$ are described and classified. For a fixed vector space $V$ of dimension…

Rings and Algebras · Mathematics 2017-01-27 A. L. Agore , G. Militaru

We investigate the behavior of extension monads, introduced in the 1990s by the second author, in terms of structure results for infinitely many finitary operations and common constructions in varieties or categories of algebras.…

Logic · Mathematics 2025-08-11 Danielle Bowerman , Matt Insall

In this paper, we deal with a notion of Banach space-valued mappings defined on a set consisting of finite graphs with uniformly bounded vertex degree. These functions will be endowed with certain boundedness and additivity criteria. We…

Combinatorics · Mathematics 2015-01-14 Felix Pogorzelski

In a previous paper the second author introduced a compact topology on the space of closed ideals of a unital Banach algebra A. If A is separable then this topology is either metrizable or else neither Hausdorff nor first countable. Here it…

Functional Analysis · Mathematics 2007-05-23 J. F. Feinstein , D. W. B. Somerset

Let $K$ be a normal subgroup of the finite group $H$. To a block of a $K$-interior $H$-algebra we associate a group extension, and we prove that this extension is isomorphic to an extension associated to a block given by the Brauer…

Representation Theory · Mathematics 2011-12-02 Tiberiu Coconet

We introduce the notion of \emph{topo-symmetric extensions} of topological groups, a new generalization of classical group extensions that incorporates both topological and symmetry constraints. We define morphisms between such extensions,…

General Mathematics · Mathematics 2025-10-02 Es-said En-naoui

We study representations of Banach algebras on reflexive Banach spaces. Algebras which admit such representations which are bounded below seem to be a good generalisation of Arens regular Banach algebras; this class includes dual Banach…

Functional Analysis · Mathematics 2010-03-16 Matthew Daws

We study a notion of indecomposability in differential algebraic groups which is inspired by both model theory and differential algebra. After establishing some basic definitions and results, we prove an indecomposability theorem for…

Logic · Mathematics 2014-10-24 James Freitag

UNIFORM algebras have been extensively investigated because of their importance in the theory of uniform approximation and as examples of complex Banach algebras. An interesting question is whether analogous algebras exist when a complete…

Functional Analysis · Mathematics 2012-01-31 Jonathan W. Mason

We investigate when a skew polynomial extension T = R[x; {\sigma}, {\delta}] of a Hopf algebra R admits a Hopf algebra structure, substantially generalising a theorem of Panov. When this construction is applied iteratively in characteristic…

Rings and Algebras · Mathematics 2014-08-06 K. A. Brown , S. O'Hagan , J. J. Zhang , G. Zhuang

Let $T$ be a Banach algebra homomorphism from a Banach algebra $\mathcal B$ to a Banach algebra $\mathcal A$ with $\|T\|\leq 1$. Recently it has been obtained some results about Arens regularity and also various notions of amenability of…

Functional Analysis · Mathematics 2015-02-19 F. Abtahi , A. Ghafarpanah , A. Rejali

Let $A$ be a Banach algebra and $M$ be a Banach right $A$-module. A linear map $\delta : M\to M$ is called a generalized derivation if there exists a derivation $d : A \to A$ such that $$\delta(xa)=\delta(x)a + x d(a) \quad (a \in A, x \in…

Functional Analysis · Mathematics 2021-07-23 Gh. Abbaspour , M. S. Moslehian , A. Niknam

We establish the exponential law for suitably topologies on spaces of vector-valued smooth functions on topological groups, where smoothness is defined by using differentiability along continuous one-parameter subgroups. As an application,…

Functional Analysis · Mathematics 2014-02-26 Daniel Beltita , Mihai Nicolae

We show how a novel construction of the sheaf of Cherednik algebras on a quotient orbifold Y=X/G by virtue of formal geometry in author's prior work leads to results for the sheaf of Cherednik algebra which until recently were viewed as…

Quantum Algebra · Mathematics 2021-10-04 Alexander Vitanov

We study the space of orthogonally additive $n$-homogeneous polynomials on $C(K)$. There are two natural norms on this space. First, there is the usual supremum norm of uniform convergence on the closed unit ball. As every orthogonally…

Functional Analysis · Mathematics 2018-07-10 Christopher Boyd , Raymond A. Ryan , Nina Snigireva