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Related papers: Some realcompact spaces

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We prove that the category of c-spaces with continuous maps is not cartesian closed. As a corollary the category of locally finitary compact spaces with continuous maps is also not cartesian closed.

Logic in Computer Science · Computer Science 2023-06-22 Z. Lyu , X. Xie , H. Kou

In this survey article we provide an introduction to submanifold geometry in symmetric spaces of noncompact type. We focus on the construction of examples and the classification problems of homogeneous and isoparametric hypersurfaces, polar…

Differential Geometry · Mathematics 2019-01-16 Jose Carlos Diaz-Ramos , Miguel Dominguez-Vazquez , Victor Sanmartin-Lopez

S. Garcia-Ferreira and H. Ohta gave a construction that was intended to produce a tau-pseudocompact space, which has a regular-closed zero set A and a regular-closed C-embedded set B such that neither A nor B is tau-pseudocompact. We show…

General Topology · Mathematics 2009-03-14 Jerry E. Vaughan

We characterize 1-complemented subspaces of finite codimension in strictly monotone one-$p$-convex, $2<p<\infty,$ sequence spaces. Next we describe, up to isometric isomorphism, all possible types of 1-unconditional structures in sequence…

Functional Analysis · Mathematics 2016-09-06 Beata Randrianantoanina

We present a notion of precompactness, and study some of its properties, in the context of apartness spaces whose apartness structure is not necessarily induced by any uniform one. The presentation lies entirely with a Bishop-style…

Logic in Computer Science · Computer Science 2015-07-01 Douglas S Bridges

Every compact symmetric space $M$ admits a dual noncompact symmetric space $\check{M}$. When $M$ is a generalized Grassmannian, we can view $\check{M}$ as a open submanifold of it consisting of space-like subspaces \cite{HL}. Motivated from…

Algebraic Geometry · Mathematics 2018-11-08 Yunxia Chen , Yongdong Huang , Naichung Conan Leung

In this paper we have obtained two more characterizations of nearly pseudocompact spaces.

General Topology · Mathematics 2022-03-28 Biswajit Mitra , Sanjib Das

Motivated by Exel's inverse semigroup approach to combinatorial C*-algebras, in a previous work the authors defined an inverse semigroup associated with a labelled space. We construct a representation of the C*-algebra of a labelled space,…

Operator Algebras · Mathematics 2019-09-11 Giuliano Boava , Gilles G. de Castro , Fernando de L. Mortari

This paper studies direct limits of full upper triangular matrix algebras with embeddings which are not *-extendible. A representation of the limit algebra is found so that the generated C*-algebra is the C*-envelope. Some examples are…

funct-an · Mathematics 2008-02-03 Alan Hopenwasser , Cecelia Laurie

We consider the covering of a ball in certain normed spaces by its congruent subsets and show that if the finite number of sets is not greater than the dimensionality of the space, then the centre of the ball either belongs to the interior…

Functional Analysis · Mathematics 2017-08-07 Sergij V. Goncharov

\emph{Scalable spaces} are simply connected compact manifolds or finite complexes whose real cohomology algebra embeds in their algebra of (flat) differential forms. This is a rational homotopy invariant property and all scalable spaces are…

Geometric Topology · Mathematics 2022-09-16 Aleksandr Berdnikov , Fedor Manin

Two examples of spectral triples with non-integer dimension spectrum are considered. These triples involve commutative C*-algebras. The first example has complex dimension spectrum and trivial differential algebra. The other is a parameter…

Mathematical Physics · Physics 2008-09-29 R. Trinchero

We show that nuclear C*-algebras have a refined version of the completely positive approximation property, in which the maps that approximately factorize through finite dimensional algebras are convex combinations of order zero maps. We use…

Operator Algebras · Mathematics 2012-04-27 Ilan Hirshberg , Eberhard Kirchberg , Stuart White

The main result states that a connected conic singular sub-manifold of a Riemannian manifold, compact when the ambient manifold is non-Euclidean, is Lipschitz Normally Embedded: the outer and inner metric space structures are metrically…

Differential Geometry · Mathematics 2023-06-27 André Costa , Vincent Grandjean , Maria Michalska

We characterise the strictly closed left invariant C*-subalgebras of the C*-algebra C_b(G) of bounded continuous functions on a locally compact group G. On the dual side, we characterise the strictly closed invariant C*-subalgebras of the…

Operator Algebras · Mathematics 2011-10-26 Pekka Salmi

Motivated by advances in categorical probability, we introduce non-commutative almost everywhere (a.e.) equivalence and disintegrations in the setting of C*-algebras. We show that C*-algebras (resp. W*-algebras) and a.e. equivalence classes…

Quantum Physics · Physics 2023-12-18 Arthur J. Parzygnat , Benjamin P. Russo

We give a simple and explicit example of a complex Banach space which is not isomorphic to its complex conjugate, and hence of two real-isomorphic spaces which are not complex-isomorphic.

Functional Analysis · Mathematics 2008-02-03 Nigel J. Kalton

We study the class of compact convex subsets of a topological vector space which admits a strictly convex and lower semicontinuous function. We prove that such a compact set is embeddable in a strictly convex dual Banach space endowed with…

Functional Analysis · Mathematics 2015-10-28 L. García-Lirola , J. Orihuela , M. Raja

We discuss some notions of compactness and convergence relative to a specified family F of subsets of some topological space X. The two most interesting particular cases of our construction appear to be the following ones. (1) The case in…

General Topology · Mathematics 2011-06-07 Paolo Lipparini

In this paper we will give two different natural generalizations of compact spaces and connected spaces simultaneously. We will show that these generalizations coincide for the subspaces of the real line and that they differ for subspaces…

General Topology · Mathematics 2024-04-08 Nebojsa Elez , Ognjen Papaz