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In this article we prove various results about transferring or lifting $\mathrm{A}_\infty$-algebra structures along quasi-isomorphisms over a commutative ring.

K-Theory and Homology · Mathematics 2025-10-24 Janina C. Letz

Let $X$ be a connected CW complex. Let $\mathcal{V}$ be a symplectic vector bundle of rank $2mn$ over $X$, and let $\mathcal{A}$ be a topological Azumaya algebra of degree $2mn$ with a symplectic involution over a $X$. We give conditions…

Algebraic Topology · Mathematics 2025-08-26 Niny Arcila-Maya

In this note we discuss some examples of non torsion and non algebraic cohomology classes for varieties over finite fields. The approach follows the construction of Atiyah-Hirzebruch and Totaro.

Algebraic Geometry · Mathematics 2014-01-09 Alena Pirutka , Nobuaki Yagita

We discuss an universal bordism invariant obtained from the Atiyah-Patodi-Singer eta-invariant from the analytic and homotopy theoretic point of view. Classical invariants like the Adams e-invariant, $\rho$-invariants and $String$-bordism…

Algebraic Topology · Mathematics 2017-06-14 Ulrich Bunke

The main goal of the paper is the discussion of a deeper interaction between matrix theory over polynomial rings over a field and typical methods of commutative algebra and related algebraic geometry. This is intended in the sense of…

Commutative Algebra · Mathematics 2024-06-07 Zaqueu Ramos , Aron Simis

We analyze the algebra of observables of a charged particle on a noncommutative torus in a constant magnetic field. We present a set of generators of this algebra which coincide with the generators for a commutative torus but at a different…

High Energy Physics - Theory · Physics 2009-11-07 Bogdan Morariu , Alexios P. Polychronakos

We study the analogue of tautological rings of fibre bundles in the context of fibrations with Poincar\' e fibre, i.e. the ring obtained by fibre integrating powers of the fibrewise Euler class. We discuss how to compute the Euler ring with…

Algebraic Topology · Mathematics 2026-05-06 Nils Prigge

We give an axiomatic framework for studying the representation theory of towers of algebras. We introduce a new class of algebras, contour algebras, generalising (and interpolating between) blob algebras and cyclotomic Temperley-Lieb…

Representation Theory · Mathematics 2007-05-23 Anton Cox , Paul Martin , Alison Parker , Changchang Xi

This paper combines two studies: a topological semantics for epistemic notions and abstract argumentation theory. In our combined setting, we use a topological semantics to represent the structure of an agent's collection of evidence, and…

Artificial Intelligence · Computer Science 2017-07-28 Chenwei Shi , Sonja Smets , Fernando R. Velázquez-Quesada

Following an idea of Totaro, we prove that the classical integral cycle class map from algebraic cycles to \'etale cohomology factors through a quotient of $\ell$-adic \'etale cobordism over an algebraically closed field of positive…

Algebraic Geometry · Mathematics 2010-01-06 Gereon Quick

In this paper, we define representations and cohomology of weighted Rota-Baxter Lie algebras. As applications of cohomology, we study abelian extensions and formal $1$-parameter deformations weighted Rota-Baxter Lie algebras. Finally, we…

Representation Theory · Mathematics 2021-09-07 Apurba Das

In this paper, first we introduce the concept of modified Rota-Baxter Lie-Yamaguti algebras. Then the cohomology of a modified Rota-Baxter Lie-Yamaguti algebra with coefficients in a suitable representation is established. As applications,…

Rings and Algebras · Mathematics 2024-02-01 Wen Teng , Shuangjian Guo

We develop a theory of group actions and coverings on Brauer graphs that parallels the theory of group actions and coverings of algebras. In particular, we show that any Brauer graph can be covered by a tower of coverings of Brauer graphs…

Representation Theory · Mathematics 2012-12-03 Edward L Green , Sibylle Schroll , Nicole Snashall

The crystalline differential operators on a smooth variety X give rise to a non-split Azumaya algebra over the cotangent bundle of the Frobenius twist X'. In some cases, this Azumaya algebra splits when restricted to finite covers of X'. In…

Algebraic Geometry · Mathematics 2026-05-29 Siqing Zhang

Standard combinatorial construction, due to Kontsevich, associates to any $\ai$-algebra with an invariant inner product, an inhomogeneous class in the cohomology of the moduli spaces of Riemann surfaces with marked points. We propose an…

Algebraic Topology · Mathematics 2008-01-08 Alastair Hamilton , Andrey Lazarev

A finite-dimensional unital and associative algebra over $\mathbb{R}$, or what we shall call simply "an algebra" in this paper for short, generalities the construction by which we derive the complex numbers by "adjoining an element $i$" to…

Rings and Algebras · Mathematics 2017-08-04 Nathan BeDell

This paper is devoted to studying deformation, cohomology theory of Rota-Baxter pre-Lie algebras of arbitrary weights. First we give the notion of a new representation of a Rota-Baxter pre-Lie algebra of arbitrary weight and define the…

Rings and Algebras · Mathematics 2022-08-09 Shuangjian Guo , Yufei Qin , Kai Wang , Guodong Zhou

Let A be an Azumaya algebra of constant rank n^2 over a Hensel pair (R,I) where R is a semilocal ring with n invertible in R. Then the reduced Whitehead group SK(A) coincides with its reduction SK(A/IA).

Rings and Algebras · Mathematics 2008-12-19 R. Hazrat

We show how to calculate the operator algebra and the operator Lie algebra of a stochastic labelled-graph grammar. More specifically, we carry out a generic calculation of the product (and therefore the commutator) of time-evolution…

Formal Languages and Automata Theory · Computer Science 2019-09-11 Eric Mjolsness

We determine multiplication and convolution topological algebras for classes of $\omega$-ultradifferentiable functions of Beurling type. Hypocontinuity and discontinuity of the multiplication and convolution mappings are also investigated.

Functional Analysis · Mathematics 2022-01-19 Angela A. Albanese , Claudio Mele