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Related papers: A Short Study of Alexandroff Spaces

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We define a class of spaces on which one may generalise the notion of compactness following motivating examples from higher-dimensional number theory. We establish analogues of several well-known topological results (such as Tychonoff's…

General Topology · Mathematics 2019-02-11 Raven Waller

In the following text we show that the Alexandroff space $X$ is uniformizable if and only if the collection of all smallest neighbourhoods is a partition of $X$. Moreover the Alexandroff space $X$ is uniformizable and functional Alexandroff…

General Topology · Mathematics 2023-09-01 Fatemah Ayatollah Zadeh Shirazi , Elahe Hakimi , Arezoo Hosseini , Reza Rezavand

Not all convex functions on $\mathbb{R}^n$ have finite minimizers; some can only be minimized by a sequence as it heads to infinity. In this work, we aim to develop a theory for understanding such minimizers at infinity. We study astral…

Optimization and Control · Mathematics 2025-12-10 Miroslav Dudík , Robert E. Schapire , Matus Telgarsky

In this note, we estimate the upper bound of volume of closed positively or nonnegatively curved Alexandrov space $X$ with strictly convex boundary. We also discuss the equality case. In particular, the Boundary Conjecture holds when the…

Differential Geometry · Mathematics 2020-10-23 Jian Ge

We define regular points of an extremal subset in an Alexandrov space and study their basic properties. We show that a neighborhood of a regular point in an extremal subset is almost isometric to an open subset in Euclidean space and that…

Differential Geometry · Mathematics 2023-01-18 Tadashi Fujioka

With the goal of solving optimisation problems on non-Riemannian manifolds, such as geometrical surfaces with sharp edges, we develop and prove the convergence of a forward-backward method in Alexandrov spaces with curvature bounded both…

Optimization and Control · Mathematics 2026-04-03 Heikki von Koch , Tuomo Valkonen

In this paper, we generalize a theorem {\`a} la Alexandrov of Wang, Wang and Zhang [WWZ] for closed codimension-two spacelike submanifolds in the Minkowski spacetime for an adapted CMC condition .

Differential Geometry · Mathematics 2019-09-12 Oussama Hijazi , Sebastian Montiel , Simon Raulot

Denote by $\mathcal{A}(\kappa)$ the set of all compact Alexandrov surfaces with curvature bounded below by $\kappa$ without boundary, endowed with the topology induced by the Gromov-Hausdorff metric. We determine the connected components of…

Metric Geometry · Mathematics 2013-11-01 Joël Rouyer , Costin Vîlcu

We construct an Alexander type invariant for oriented doodles from a deformation of the Tits representation of the twin group and from the Chebyshev polynomials of second kind. Similar to the Alexander polynomial, our invariant vanishes on…

Geometric Topology · Mathematics 2020-09-21 Bruno Cisneros , Marcelo Flores , Jesús Juyumaya , Christopher Roque-Márquez

We develop a structure theory for RCD spaces with curvature bounded above in Alexandrov sense. In particular, we show that any such space is a topological manifold with boundary whose interior is equal to the set of regular points. Further…

Differential Geometry · Mathematics 2019-09-10 Vitali Kapovitch , Martin Kell , Christian Ketterer

We investigate harmonic maps from weighted graphs into metric spaces that locally admit unique centers of gravity, like Alexandrov spaces with upper curvature bounds. We prove an existence result by constructing an iterative geometric…

Metric Geometry · Mathematics 2007-08-22 J. Jost , L. Todjihounde

The main purpose of this paper is to introduce and study the primal-proximity spaces. Also, we define two new operators via primal proximity spaces and investigate some of their fundamental properties. In addition, we obtain a new topology,…

General Topology · Mathematics 2024-12-20 Ahmad Al-Omari , Murad Ozcog , Santanu Acharjee

This book provides a gentle introduction to fractional Sobolev spaces, which play a central role in the calculus of variations, partial differential equations, and harmonic analysis. The first part deals with fractional Sobolev spaces of…

Analysis of PDEs · Mathematics 2023-03-13 Giovanni Leoni

Comparison of $1$-dimensional distance functions is a basic tool in Alexandrov geometry and it is used to characterize spaces with curvature bounded above or below. For the zero curvature bound there is a differential inequality which…

Metric Geometry · Mathematics 2017-01-19 Murat Limoncu , Şahin Koçak

We introduce the notion of good coverings of metric spaces, and prove that if a metric space admits a good covering, then it has the same locally Lipschitz homotopy type as the nerve complex of the covering. As an application, we obtain a…

Metric Geometry · Mathematics 2018-08-02 Ayato Mitsuishi , Takao Yamaguchi

We present a short proof of the Alexandrov-Fenchel inequalities for mixed volumes of convex bodies.

Metric Geometry · Mathematics 2019-06-25 D. Cordero-Erausquin , B. Klartag , Q. Merigot , F. Santambrogio

The purpose of this note is to discuss how various Sobolev spaces defined on multiple cones behave with respect to density of smooth functions, interpolation and extension/restriction to/from $\RR^n$. The analysis interestingly combines use…

Classical Analysis and ODEs · Mathematics 2010-05-31 Pascal Auscher , Nadine Badr

In this expository note, we present a transparent proof of Toponogov's theorem for Alexandrov spaces in the general case, not assuming local compactness of the underlying metric space. More precisely, we show that if M is a complete…

Metric Geometry · Mathematics 2012-07-26 Urs Lang , Viktor Schroeder

In this paper, we introduce round and sleek topological spaces and study their properties.

General Topology · Mathematics 2022-10-28 Jitender Singh

In this paper we discuss the sufficient and necessary conditions for multiple Alexandrov spaces being glued to an Alexandrov space. We propose a Gluing Conjecture, which says that the finite gluing of Alexandrov spaces is an Alexandrov…

Differential Geometry · Mathematics 2020-03-24 Jian Ge , Nan Li
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