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Given a sequence of automorphisms of the polydisk, we show that the associated composition semigroup homomorphisms on the ball of bounded holomorphic functions on the polydisk admit a universal inner function if a certain condition on the…

Complex Variables · Mathematics 2022-04-18 Timothy G. Clos

We show that the theories of some (ordered) central simple algebras with involution over real closed fields are model-complete or admit quantifier elimination, and characterize positive cones in terms of morphisms into models of some of…

Logic · Mathematics 2025-03-06 Vincent Astier

The paper presents a criterion for a C*-algebra to be a coefficient algebra associated with a given endomorphism

Operator Algebras · Mathematics 2007-05-23 V. I. Bakhtin , A. V. Lebedev

We prove that a quasi-finite endomorphism of an algebraic variety over an algebraically closed field of characteristic zero, that is injective on the complement of a closed subvariety, is an automorphism. We also prove that an endomorphism…

Algebraic Geometry · Mathematics 2021-04-02 Nilkantha Das

We prove that the algebra of invariants of a complete path algebra under the action of a homogeneous group of continuous algebra automorphisms is a complete path algebra and preserves finite or tame representation type.

Rings and Algebras · Mathematics 2026-03-27 Samuel Quirino

It is shown that universal algebras that are injective in their equational classes are characterized by internal property that can be called completeness. We define universal algebra $A$ as complete (closed to simple extensions) if for each…

Commutative Algebra · Mathematics 2021-12-14 Pavlo Dzikovskyi

Let $G$ be a closed highly homogeneous subgroup of $S_{\infty}$ not involving circular orderings. We show that the closure of a conjugacy class from $G$ contains a conjugacy class which is comeagre in it. Furthermore, we show that the…

Logic · Mathematics 2025-04-23 Monika Drzewiecka , Aleksander Ivanov , Bartosz Mokry

In this paper we consider the problem of deformation quantization of the algebra of polynomial functions on coadjoint orbits of semisimple lie groups. The deformation of an orbit is realized by taking the quotient of the universal…

Quantum Algebra · Mathematics 2007-05-23 R. Fioresi , M. A. Lledo

We show that symmetry in the vanishing of cohomology holds for graded modules over quantum complete intersections. Moreover, symmetry holds for all modules if the algebra is symmetric.

K-Theory and Homology · Mathematics 2008-11-27 Petter Andreas Bergh

The coalgebra approach to the construction of classical integrable systems from Poisson coalgebras is reviewed, and the essential role played by symplectic realizations in this framework is emphasized. Many examples of Hamiltonians with…

Mathematical Physics · Physics 2009-07-22 Angel Ballesteros , Alfonso Blasco , Francisco J. Herranz , Fabio Musso , Orlando Ragnisco

This short note provides a symplectic analogue of Vaisman's theorem in complex geometry. Namely, for any compact symplectic manifold satisfying the hard Lefschetz condition in degree 1, every locally conformally symplectic structure is in…

Symplectic Geometry · Mathematics 2024-04-08 Mehdi Lejmi , Scott O. Wilson

We prove in an elementary fashion that the image of a commutative monotone $\sigma$-complete $C^*$-algebra under a $\sigma$-normal morphism is again monotone $\sigma$-complete and give an application of this result in spectral theory.

Operator Algebras · Mathematics 2007-10-15 Marcel de Jeu

In this paper it is investigated whether various shape homology theories satisfy the Universal Coefficients Formula (UCF). It is proved that pro-homology and strong homology satisfy UCF in the class FAB of finitely generated abelian groups,…

Algebraic Topology · Mathematics 2013-05-02 Andrei V. Prasolov

A Lie algebra $\mathfrak{g}_\mathbb{Q}$ over $\mathbb{Q}$ is said to be $\mathbb{R}$-universal if every homomorphism from $\mathfrak{g}_\mathbb{Q}$ to $\mathfrak{gl}(n,\mathbb{R})$ is conjugate to a homomorphism into…

Representation Theory · Mathematics 2015-04-28 Dave Witte Morris

We consider the algebraization problem for principal bundles with reductive structure group, defined on the complement of a closed subset Z in a proper formal scheme. We show that, when Z is of codimension at least 3, an algebraization…

Algebraic Geometry · Mathematics 2008-03-07 Vladimir Baranovsky

We prove a convolution formula for the conjugacy classes in symmetric groups conjectured by the second author. A combinatorial interpretation of coefficients is provided. As a main tool we introduce new semigroup of partial permutations. We…

Combinatorics · Mathematics 2007-05-23 Vladimir Ivanov , Sergei Kerov

We show that every finite Abelian algebra A from congruence-permutable varieties admits a full duality. In the process, we prove that A also allows a strong duality, and that the duality may be induced by a dualizing structure of finite…

Rings and Algebras · Mathematics 2015-03-18 Wolfram Bentz , Pierre Gillibert , Luís Sequeira

We give characterizations of unital uniform topological algebras and saturated locally multiplicatively convex algebras by means of multiplicative linear functionals. Some automatic continuity theorems in advertibly complete uniform…

Functional Analysis · Mathematics 2014-01-03 M. El Azhari

Let $A$ be a regular category with pushouts of regular epimorphisms by regular epimorphism and $Reg(A)$ the category of regular epimorphisms in $A$. We prove that every regular epimorphism in $Reg(A)$ is an effective descent morphism if,…

Category Theory · Mathematics 2015-04-20 Tomas Everaert

Using the flatification by blow-up result of Raynaud and Gruson, we obtain new results for submersive and subtrusive morphisms. We show that universally subtrusive morphisms, and in particular universally open morphisms, are morphisms of…

Algebraic Geometry · Mathematics 2019-05-07 David Rydh