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Related papers: Quasi-theories

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The article is devoted to linear quasigroups and some of their generalizations. In the first part main definitions and notions of the theory of quasigroups are given. In the second part some elementary properties of linear quasigroups and…

Group Theory · Mathematics 2011-03-01 Abdullo Tabarov

In previous works, we introduced and studied certain categories called quasi-BPS categories associated to symmetric quivers with potential, preprojective algebras, and local surfaces. They have properties reminiscent of BPS invariants/…

Algebraic Geometry · Mathematics 2026-03-27 Tudor Pădurariu , Yukinobu Toda

In this article we provide evidence for a well-known conjecture which states that quasi-isometric simply-connected nilpotent Lie groups are isomorphic. We do so by constructing new examples which are rigid in the sense that whenever they…

Group Theory · Mathematics 2017-11-21 Manuel Amann

We revise the notion of the quasi-sectorial contractions. Our main theorem establishes a relation between semigroups of quasi-sectorial contractions and a class of m-sectorial generators. We discuss a relevance of this kind of contractions…

Functional Analysis · Mathematics 2007-11-06 V. A. Zagrebnov

We present a variation of quasi-isometry to approach the problem of defining a geometric notion equivalent to commensurability. In short, this variation can be summarized as "quasi-isometry with uniform parameters for a large enough family…

Group Theory · Mathematics 2010-06-01 Andreas Lochmann

We introduce a new notion, called quasi-holomorphic maps. These are real smooth maps equipped with a structure that imitates the singularities and singularity stratifications of holomorphic maps on the source and target manifolds, although…

Geometric Topology · Mathematics 2025-11-04 András Csépai , András Szűcs

In nature, one observes that a K-theory of an object is defined in two steps. First a "structured" category is associated to the object. Second, a K-theory machine is applied to the latter category to produce an infinite loop space. We…

K-Theory and Homology · Mathematics 2013-04-03 Nicolas Michel

We present an Eilenberg-Steenrod-like axiomatic framework for equivariant coarse homology and cohomology theories. We also discuss a general construction of such coarse theories from topological ones and the associated transgression maps. A…

Algebraic Topology · Mathematics 2022-07-27 Christopher Wulff

Tate cohomology has been generalised by several authors using different constructions that have applications in group theory, ring theory and homotopical algebra. Therefore, there is a need for a uniform account that explains why their…

Group Theory · Mathematics 2026-04-02 Max Gheorghiu

We use quasi-orders to describe the structure of C-groups. We do this by associating a quasi-order to each compatible C-relation of a group, and then give the structure of such quasi-ordered groups. We also reformulate in terms of…

Logic · Mathematics 2018-10-26 Gabriel Lehéricy

In [8](arXiv:2111.06159) we introduced the notion of a k-almost-quasifibration. In this article we update this definition and call it a k-c-quasifibration. This will help us to relate it to quasifibrations. We study some basic properties of…

Algebraic Topology · Mathematics 2022-08-16 S. K. Roushon

A quasi-schemoid is a small category whose morphisms are colored with appropriate combinatorial data. In this note, Mitchell's embedding theorem for a tame schemoid is established. The result allows us to give a cofibrantly generated model…

Category Theory · Mathematics 2016-02-29 Katsuhiko Kuribayashi , Yasuhiro Momose

The aim of this paper is to develop the theory of Hom-coalgebras and related structures. After reviewing some key constructions and examples of quasi-deformations of Lie algebras involving twisted derivations and giving rise to the class of…

Rings and Algebras · Mathematics 2008-11-24 Abdenacer Makhlouf , Sergei Silvestrov

We present a general theory of quasiprobability distributions on phase spaces of quantum systems whose dynamical symmetry groups are (finite-dimensional) Lie groups. The family of distributions on a phase space is postulated to satisfy the…

Quantum Physics · Physics 2009-10-30 C. Brif , A. Mann

We develop a quasisymmetric analogue of the theory of Schubert cycles, building off of our previous work on a quasisymmetric analogue of Schubert polynomials and divided differences. Our constructions result in a natural geometric…

Algebraic Geometry · Mathematics 2024-10-22 Philippe Nadeau , Hunter Spink , Vasu Tewari

We introduce quasi-Hopf $*$-algebras i.e. quasi-Hopf algebras equipped with a conjugation (star) operation. The definition of quasi-Hopf $*$-algebras proposed ensures that the class of quasi-Hopf $*$-algebras is closed under twisting and…

Quantum Algebra · Mathematics 2007-05-23 M. D. Gould , T. Lekatsas

In this paper, we study a special class of quasi-homomorphisms, i.e. quasi-retractions from a group to its subgroups. We first give some algebraic and geometric properties of quasi-retracts and then propose a theory of quasi-split short…

Group Theory · Mathematics 2025-08-21 Renxing Wan

We use quantum and Floer homology to construct (partial) quasi-morphisms on the universal cover of the group of compactly supported Hamiltonian diffeomorphisms for a certain class of non-closed strongly semi-positive symplectic manifolds…

Symplectic Geometry · Mathematics 2016-05-10 Sergei Lanzat

We define algebras of quasi-quaternion type, which are symmetric algebras of tame representation type whose stable module category has certain structure similar to that of the algebras of quaternion type introduced by Erdmann. We observe…

Representation Theory · Mathematics 2014-04-29 Sefi Ladkani

This is a survey about certain "almost homomorphisms" and "almost linear" functionals (called quasi-morphisms and quasi-states) in symplectic topology and their applications to Hamiltonian dynamics, functional-theoretic properties of…

Symplectic Geometry · Mathematics 2014-12-24 Michael Entov