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We give a characterisation of fragmentable, compact linearly order spaces. In particular, we show that if $K$ is a compact, fragmentable, linearly ordered space then $K$ is a Radon-Nikod\'{y}m compact. In addition, we obtain some…

Functional Analysis · Mathematics 2008-11-14 R. J. Smith

We prove that every fragmentable linearly ordered compact space is almost totally disconnected. This combined with a result of Arvanitakis yields that every linearly ordered quasi Radon-Nikodym compact space is Radon-Nikodym, providing a…

General Topology · Mathematics 2009-03-03 Antonio Avilés

We provide a characterization of continuous images of Radon-Nikodym compacta lying in a product of real lines and model on it a method for constructing natural examples of such continuous images.

General Topology · Mathematics 2010-01-26 Alexander D. Arvanitakis , Antonio Avilés

A compact space $K$ is Radon-Nikod\'{y}m if there is a lower semi-continuous metric fragmenting $K$. In this note, we show that, under $\diamondsuit (\mathrm{non}{\mathcal{M}})$, there is a Radon-Nikod\'{y}m compact space of weight…

Functional Analysis · Mathematics 2025-04-15 Arturo Martínez-Celis , Adam Morawski

A compact space is said to be weakly Radon-Nikod\'ym if it is homeomorphic to a weak*-compact subset of the dual of a Banach space not containing an isomorphic copy of $\ell_1$. In this work we provide an example of a continuous image of a…

Functional Analysis · Mathematics 2015-09-18 Gonzalo Martínez-Cervantes

Let X be a separable Banach space and Y a space which has the Radon-Nikodym property. In this work, we show that L(X, Y) has the Radon-Nikodym property, if L(X, Y) is weakly locally uniformly convex or if L(X, Y) is a weakly compactly gen-…

Functional Analysis · Mathematics 2016-03-24 M. Daher

We construct a continuous image of a Radon-Nikod\'ym compact space which is not Radon-Nikod\'ym compact, solving the problem posed in the 80ties by Isaac Namioka.

Functional Analysis · Mathematics 2019-12-19 Antonio Avilés , Piotr Koszmider

A topological space $X$ is said to be {\em $Y$-rigid} if any continuous map $f:X\rightarrow Y$ is constant. In this paper we construct a number of examples of regular countably compact $\mathbb R$-rigid spaces with additional properties…

General Topology · Mathematics 2021-10-11 Serhii Bardyla , Lyubomyr Zdomskyy

We prove that a continuous image of a Radon-Nikod\'ym compact space of weight less than b is Radon-Nikod\'ym compact. As a Banach space counterpart, subspaces of Asplund generated Banach spaces of density character less than b are Asplund…

Functional Analysis · Mathematics 2014-09-15 Antonio Avilés

We give necessary and sufficient conditions for a Banach space $X$ having the Radon-Nikod\'{y}m property in terms of polynomial spline sequences.

Functional Analysis · Mathematics 2018-07-06 Markus Passenbrunner

Yu. I. Merzljakov developed a method of splittable coordinates which helps to verify the linearity of some groups, he established some fundamental results using this method. In this paper we use the method of splittable coordinates and find…

Group Theory · Mathematics 2007-05-23 V. G. Bardakov , O. V. Bryukhanov

We prove that every Lindel\"of scattered subspace of a $\Sigma$-product of first-countable spaces is $\sigma$-compact. In particular, we obtain the result stated in the title. This answers some questions of Tkachuk from [Houston J. Math. 48…

General Topology · Mathematics 2025-01-28 Antonio Avilés , Mikołaj Krupski

We prove that a compact space is monotonically Sokolov if and only if it is monotonically $\omega$-monolithic. This gives answers to several questions of R. Rojas-Hernandez and V. V. Tkachuk.

General Topology · Mathematics 2014-11-26 Marek Cuth

A transitive compact foliated space is shown to be a Riemannian foliation if and only if it is locally connected, finite dimensional, strongly equicontinuous and quasi-analytic, and the closure of its holonomy pseudogroup is quasi-analytic.

Geometric Topology · Mathematics 2013-11-15 Jesús A. Álvarez López , Alberto Candel

A space is od-compact (resp. od-Lindel\"of) provided any cover by open dense sets has a finite (resp. countable) subcover. We first show with simple examples that these properties behave quite poorly under finite or countable unions. We…

General Topology · Mathematics 2015-03-24 Mathieu Baillif

Given positive measures $\nu,\mu$ on an arbitrary measurable space $(\Omega, \mathcal F)$, we construct a sequence of finite partitions $(\pi_n)_n$ of $(\Omega, \mathcal F)$ s.t. $$ \sum_{A\in \pi_n: \mu(A)>0} 1_{A} \frac{\nu(A)}{\mu(A)}…

Classical Analysis and ODEs · Mathematics 2019-09-10 Oleksii Mostovyi , Pietro Siorpaes

We prove that under certain combinatorial conditions, the realization spaces of line arrangements on the complex projective plane are connected. We also give several examples of arrangements with eight, nine and ten lines which have…

Algebraic Geometry · Mathematics 2011-05-18 Shaheen Nazir , Masahiko Yoshinaga

It is well known that every bounded below and non increasing sequence in the real line converges. We give a version of this result valid in Banach spaces with the Radon-Nikodym property, thus extending a former result of A. Proch\'azka.

Functional Analysis · Mathematics 2013-03-08 Robert Deville , Óscar Madiedo

Let Z be a complex space and let S be a compact set in C^n x Z which is fibered over R^n (the real subspace of C^n). We give a necessary and sufficient condition for S to be a Stein compactum.

Complex Variables · Mathematics 2011-01-18 Franc Forstneric , Erlend Fornaess Wold

We show that a compact length space is polyhedral if a small spherical neighborhood of any point is conic.

Differential Geometry · Mathematics 2018-07-09 Nina Lebedeva , Anton Petrunin
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