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Related papers: On weakly Radon-Nikod\'ym compact spaces

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We prove that the tangent bundle of an inner symmetric space $M$ of compact type is weakly complex if and only if $M$ is a Riemannian product $M_1\times...\times M_k$, each $M_i$ being an even-dimensional round sphere or Hermitian…

Differential Geometry · Mathematics 2010-09-03 Andrei Moroianu , Uwe Semmelmann

Cocompactness is a property of embeddings between two Banach spaces, similar to but weaker than compactness, defined relative to some non-compact group of bijective isometries. In presence of a cocompact embedding, bounded sequences (in the…

Functional Analysis · Mathematics 2016-01-20 Cyril Tintarev

It is shown that the collection of weakly almost periodic functionals on the convolution algebra of a commutative Hopf von Neumann algebra is a C$^*$-algebra. This implies that the weakly almost periodic functionals on $M(G)$, the measure…

Functional Analysis · Mathematics 2011-01-14 Matthew Daws

A Riemannian manifold $M$ is called weakly symmetric if any two points in $M$ can be interchanged by an isometry. The compact ones have been well understood, and the main remaining case is that of 2-step nilpotent Lie groups. We give a…

Differential Geometry · Mathematics 2025-03-04 Y. Nikolayevsky , W. Ziller

We show that a geodesic metric space which does not admit bilipschitz embeddings into Banach spaces with the Radon-Nikod\'ym property does not necessarily contain a bilipschitz image of a thick family of geodesics. This is done by showing…

Metric Geometry · Mathematics 2014-11-14 Mikhail Ostrovskii

We show that the Lipschitz-free space with the Radon--Nikod\'{y}m property and a Daugavet point recently constructed by Veeorg is in fact a dual space isomorphic to $\ell_1$. Furthermore, we answer an open problem from the literature by…

The Erberlein-Smulian Theorem asserts that for complete normed spaces, that is Banach spaces, a subset is weak compact if and only if it is weak sequentially compact. In this paper it is shown that the completeness of the normed space is…

Functional Analysis · Mathematics 2007-05-23 Wha Suck Lee

For $0\leqslant \xi\leqslant \omega_1$, we define the notion of $\xi$-weakly precompact and $\xi$-weakly compact sets in Banach spaces and prove that a set is $\xi$-weakly precompact if and only if its weak closure is $\xi$-weakly compact.…

Functional Analysis · Mathematics 2019-05-30 Kevin Beanland , R. M. Causey

It is shown that if the dual of a Banach space, $X^*$, where the dual ball is weak* sequentially compact, has the weak* uniform Kadec-Klee property then $X^*$ has Property($K^*$). An example is given where the reverse implication does not…

Functional Analysis · Mathematics 2020-06-11 Tim Dalby

The KC property, a separation axiom between weakly Hausdorff and Hausdorff, requires compact subsets to be closed. Various assumptions involving local conditions, dimension, connectivity, and homotopy show certain KC-spaces are in fact…

General Topology · Mathematics 2012-08-28 Paul Fabel

Based on the concept of unbounded absolutely weakly convergence, we give new characterizations of L-weakly compact sets. As applications, we find some properties of order weakly compact operators. Also, a new characterizations of order…

Functional Analysis · Mathematics 2020-05-05 Hassan Khabaoui , Jawad H'michane , Kamal El Fahri

We study the different ways in which a weakly compact set can generate a Banach lattice. Among other things, it is shown that in an order continuous Banach lattice $X$, the existence of a weakly compact set $K \subset X$ such that $X$…

Functional Analysis · Mathematics 2015-12-31 Antonio Avilés , Antonio J. Guirao , Sebastián Lajara , José Rodríguez , Pedro Tradacete

We consider the class of weakly porous sets in Euclidean spaces. As our main goal, we give a precise characterization in terms of dyadic covering of these sets. Also, we obtain the Carleson embedding inequality for porous sets.

Functional Analysis · Mathematics 2024-10-14 Andrei Vasin

A well known result of Lozanovsky states that a Banach lattice is weakly sequentially complete if and only if it does not contain a copy of $c_{0}$. In the current paper we extend this result to the class of Banach $C(K)$ modules of finite…

Functional Analysis · Mathematics 2015-03-31 Arkady Kitover , Mehmet Orhon

Following [3] we say that a Tychonoff space $X$ is an Ascoli space if every compact subset $\mathcal{K}$ of $C_k(X)$ is evenly continuous; this notion is closely related to the classical Ascoli theorem. Every $k_\mathbb{R}$-space, hence any…

Functional Analysis · Mathematics 2015-04-17 S. Gabriyelyan , J. Kakol , G. Plebanek

We introduce the notion of compactifiable classes -- these are classes of metrizable compact spaces that can be up to homeomorphic copies ``disjointly combined'' into one metrizable compact space. This is witnessed by so-called compact…

General Topology · Mathematics 2020-02-19 A. Bartoš , J. Bobok , J. van Mill , P. Pyrih , B. Vejnar

We give some characterizations of disjointly weakly compact sets in Banach lattices, namely, those sets in whose solid hulls every disjoint sequence converges weakly to zero. As an application, we prove that a bounded linear operator from a…

Functional Analysis · Mathematics 2023-04-27 Bo Xiang , Jin Xi Chen , Lei Li

A quantum expectation is a positive linear functional of norm one on a non-commutative probability space (i.e., a C*-algebra). For a given pair of quantum expectations $\mu$ and $\lambda$ on a non-commutative probability space $A$, we…

Operator Algebras · Mathematics 2025-07-15 Fouad Naderi

In his study of the Radon Nikod\'ym property of Banach spaces, Bourgain showed (among other things) that in any closed, bounded, convex set $A$ that is nondentable, one can find a separated, weakly closed bush. In this note, we prove a…

Functional Analysis · Mathematics 2020-03-02 S. J. Dilworth , Chris Gartland , Denka Kutzarova , N. Lovasoa Randrianarivony

We characterize compact metric spaces whose locally flat Lipschitz functions separate points uniformly as exactly those that are purely 1-unrectifiable, resolving a problem of Weaver. We subsequently use this geometric characterization to…

Metric Geometry · Mathematics 2022-03-16 Ramón J. Aliaga , Chris Gartland , Colin Petitjean , Antonín Procházka