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Related papers: A note on quasi-perfect morphisms

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The paper is devoted to the study of mappings with non--bounded characteristics of quasiconformality. The analog of the theorem about radius injectivity of locally quasiconformal mappings was proved for some class of mappings. There are…

Complex Variables · Mathematics 2013-01-28 Evgeny Sevost'yanov

For a group $G$, we construct a quasi morphism from its left orderings and the map from the space of left orderings to the second bounded cohomology. We show that these maps reflect various properties of the group orderings.

Group Theory · Mathematics 2010-07-07 Tetsuya Ito

Shape theory works nice for (Hausdorff) paracompact spaces, but for spaces with no separation axioms, it seems to be quite poor. However, for finite and locally finite spaces their weak homotopy type is rather rich, and is equivalent to the…

Algebraic Topology · Mathematics 2010-12-30 Andrei V. Prasolov

We characterise proper morphisms of $\infty$-topoi in terms of a relativised notion of compactness: we show that a geometric morphism of $\infty$-topoi is proper if and only if it commutes with colimits indexed by filtered internal…

Category Theory · Mathematics 2025-03-18 Louis Martini , Sebastian Wolf

Let $K$ be a closed polydisc or ball in $\C^n$, and let $Y$ be a quasi projective algebraic manifold which is Zariski locally equivalent to $\C^p$, or a complement of an algebraic subvariety of codimension $\ge 2$ in such manifold. If $r$…

Complex Variables · Mathematics 2007-05-23 Kolarič Dejan

Let $R$ be a Noetherian ring and let $C$ be a semidualizing $R$-module. In this paper, by using the classes $ \mathcal{P}_C $ and $ \mathcal{I}_C $, we extend the notions of perfect and coperfect modules introduced by D.Rees \cite{R} and…

Commutative Algebra · Mathematics 2016-04-08 M. Rahmani , A. -J. Taherizadeh

In the present article, we investigate the following deformation problem. Let $(R,\mathfrak m)$ be a local (graded local) Noetherian ring with a (homogeneous) regular element $y \in \mathfrak m$ and assume that $R/yR$ is quasi-Gorenstein.…

Commutative Algebra · Mathematics 2026-03-03 Kazuma Shimomoto , Naoki Taniguchi , Ehsan Tavanfar

We define and develop the notion of a discretisable quasi-action. It is shown that a cobounded quasi-action on a proper non-elementary hyperbolic space $X$ not fixing a point of $\partial X$ is quasi-conjugate to an isometric action on…

Group Theory · Mathematics 2022-07-18 Alex Margolis

We introduce quasi-homomorphisms of cluster algebras, a flexible notion of a map between cluster algebras of the same type (but with different coefficients). The definition is given in terms of seed orbits, the smallest equivalence classes…

Rings and Algebras · Mathematics 2016-01-18 Chris Fraser

Directional notions in topology and analysis naturally lead to nonsymmetric structures such as quasi-metrics, quasi-uniformities, and modular spaces. In these settings, classical notions of connectedness and completion based on symmetric…

General Topology · Mathematics 2026-01-26 Philani Rodney Majozi

In this paper, we give two elementary constructions of homogeneous quasi-morphisms defined on the group of Hamiltonian diffeomorphisms of certain closed connected symplectic manifolds (or on its universal cover). The first quasi-morphism,…

Symplectic Geometry · Mathematics 2007-06-13 Pierre Py

We prove constructively the existence of surjective morphisms from affine space onto certain open subvarieties of affine space of the same dimension. For any algebraic set $Z\subset \mathbb{A}^{n-2}\subset \mathbb{A}^{n}$, we construct an…

Algebraic Geometry · Mathematics 2023-08-22 Viktor Balch Barth

In this article, we characterize the distortion elements of the group of smooth diffeomorphisms of the circle and of the group of compactly supported smooth diffeomorphisms of the real line. More precisely, we prove that, in this context,…

Dynamical Systems · Mathematics 2025-07-21 Hélène Eynard-Bontemps , Emmanuel Militon

There is a well known link from the first topic in the title to the third one. In this paper we thread that link through the second topic. The central result is a criterion for the tensor nilpotence of morphisms of perfect complexes over…

Commutative Algebra · Mathematics 2018-11-27 Luchezar L. Avramov , Srikanth B. Iyengar , Amnon Neeman

We introduce and geometrically characterize the notion of uniformly perfect Morse boundary for proper geodesic metric spaces. As a unifying result, we prove that the Morse boundary of any finitely generated, non-elementary group is…

Group Theory · Mathematics 2026-02-09 Suzhen Han , Qing Liu

This paper is about the local geometry of a real surfaces. It introduces machinery for studying families of subsets which are determined by conditions which are similar to base conditions, but also involve positivity/non-negativity. The…

alg-geom · Mathematics 2008-02-03 Dean Alvis , Bernard Johnston , James Madden

This expository article is devoted to the local theory of ultradifferentiable classes of functions, with a special emphasis on the quasianalytic case. Although quasianalytic classes are well-known in harmonic analysis since several decades,…

Classical Analysis and ODEs · Mathematics 2008-02-07 Vincent Thilliez

We show that the Hamiltonian dynamics of the self-interacting, abelian p-form theory in D=2p+2 dimensional space-time gives rise to the quasi-local structure. Roughly speaking, it means that the field energy is localized but on closed…

High Energy Physics - Theory · Physics 2007-05-23 D. Chruscinski

Grothendieck proved in EGA IV that if any integral scheme of finite type over a locally noetherian scheme X admits a desingularization, then X is quasi-excellent, and conjectured that the converse is probably true. We prove this conjecture…

Algebraic Geometry · Mathematics 2008-09-11 Michael Temkin

The article is devoted to a structure of topological spaces related with topological quasigroups. Regular and complete spaces over topological quasigroups are studied. Separations and embeddings are also investigated for them. Their…

Group Theory · Mathematics 2023-12-29 S. V. Ludkowski