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Related papers: On regular but not completely regular spaces

200 papers

An inverse limit of a sequence of covering spaces over a given space $X$ is not, in general, a covering space over $X$ but is still a lifting space, i.e. a Hurewicz fibration with unique path lifting property. Of particular interest are…

General Topology · Mathematics 2017-08-04 Gregory R. Conner , Wolfgang Herfort , Petar Pavešić

We consider the relationship between normality and semi-proximality. We give a consistent example of a first countable locally compact Dowker space that is not semi-proximal, and two ZFC examples of semi-proximal non-normal spaces. This…

General Topology · Mathematics 2024-01-22 Khulod Almontashery , Paul Szeptycki

Partial Isometries are important constructs that help give nontrivial solutions once a simple solution is known. We generalize this notion to Extended Partial Isometries and include operators which have right inverses but no left inverses…

High Energy Physics - Theory · Physics 2007-05-23 Tewodros Amdeberhan , Arvind Ayyer

In this talk we will study the partial breaking of supersymmetry in flat and anti de Sitter space. We will see that partial breaking in flat space can be accomplished using either of two representations for the massive N=1 spin-3/2…

High Energy Physics - Theory · Physics 2007-05-23 Jonathan A. Bagger , Richard Altendorfer

In a countably normed space which is a linear space equipped with a countable number of pair-wise compatible norms, we prove the existence of a common nearest point (in all norms) from a point outside a nonempty subset if this subset is…

Functional Analysis · Mathematics 2022-12-14 Moustafa M. Zakaria , Nashat Faried , Hany A. El-Sharkawy

Let $\cal P$ be a finite classical polar space of rank $d$. An $m$-regular system with respect to $(k - 1)$-dimensional projective spaces of $\cal P$, $1 \le k \le d - 1$, is a set $\cal R$ of generators of $\cal P$ with the property that…

Combinatorics · Mathematics 2021-03-18 Antonio Cossidente , Giuseppe Marino , Francesco Pavese , Valentino Smaldore

In spaces of nonpositive curvature the existence of isometrically embedded flat (hyper)planes is often granted by apparently weaker conditions on large scales. We show that some such results remain valid for metric spaces with non-unique…

Metric Geometry · Mathematics 2016-03-15 Dominic Descombes , Urs Lang

We present an algorithm for constructing the fixed point of a general non-isometric similarity of the plane.

History and Overview · Mathematics 2014-11-03 Zhigang Han , Ron Umble

I survey problems concerning Lindelof spaces which have partial set- theoretic solutions.

Logic · Mathematics 2011-04-19 Franklin D. Tall

We study combinatorial configurations with the associated point and line graphs being strongly regular. Examples not belonging to known classes such as partial geometries and their generalizations or elliptic semiplanes are constructed.…

Combinatorics · Mathematics 2025-09-30 Marién Abreu , Martin Funk , Vedran Krčadinac , Domenico Labbate

We study the Borel subsets of the plane that can be made closed by refining the Polish topology on the real line. These sets are called potentially closed. We first compare Borel subsets of the plane using products of continuous functions.…

Logic · Mathematics 2007-10-02 Dominique Lecomte

The aim of this paper is to study some examples of exponentially harmonic maps. We study such maps firstly on flat euclidean and Minkowski spaces and secondly on Friedmann-Lema\^ itre universes. We also consider some new models of…

Mathematical Physics · Physics 2009-11-07 A D Kanfon , A Füzfa , D Lambert

We introduce a geometric realization of noncommutative singularity resolutions. To do this, we first present a new conjectural method of obtaining conventional resolutions using coordinate rings of matrix-valued functions. We verify this…

Algebraic Geometry · Mathematics 2011-03-01 Charlie Beil

We consider the incompressible Euler equations on ${\mathbb R}^d$, where $d \in \{ 2,3 \}$. We prove that: (a) In Lagrangian coordinates the equations are locally well-posed in spaces with fixed real-analyticity radius (more generally, a…

Analysis of PDEs · Mathematics 2016-12-21 Peter Constantin , Igor Kukavica , Vlad Vicol

The problem of finding a point in the intersection of closed sets can be solved by the method of alternating projections and its variants. It was shown in earlier papers that for convex sets, the strategy of using quadratic programming (QP)…

Optimization and Control · Mathematics 2015-06-30 C. H. Jeffrey Pang

In this article, we re-examine some of the classical pointwise multiplication theorems in Sobolev-Slobodeckij spaces, in part motivated by a simple counter-example that illustrates how certain multiplication theorems fail in…

Analysis of PDEs · Mathematics 2021-03-01 A. Behzadan , M. Holst

We construct series of examples of exotic smooth structures on compact locally symmetric spaces of noncompact type. In particular, we obtain higher rank examples, which do not support Riemannian metric of nonpositive curvature. The examples…

Differential Geometry · Mathematics 2014-10-01 Boris Okun

Alternative iterative methods for a nonexpansive mapping in a Banach space are proposed and proved to be convergent to a common solution to a fixed point problem and a variational inequality. We give rates of asymptotic regularity for such…

Functional Analysis · Mathematics 2009-06-01 Vittorio Colao , Laurentiu Leustean , Genaro Lopez , Victoria Martin-Marquez

In the setting of CAT(k) spaces, common fixed point iterations built from prox mappings (e.g. prox-prox, Krasnoselsky-Mann relaxations, nonlinear projected-gradients) converge locally linearly under the assumption of linear metric…

Optimization and Control · Mathematics 2021-12-13 Florian Lauster , D. Russell Luke

L^p spaces of mappings taking values in arbitrary metric spaces, which we call nonlinear Lebesgue spaces, play an important role in several fields of mathematics. For instance, membership in these spaces is typically required for transport…

Functional Analysis · Mathematics 2026-03-10 Guillaume Sérieys , Alain Trouvé