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Related papers: A compactness criterion in Schauder spaces

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We propose a simple criterion of compactness in the space of fuzzy number on the space of finite dimension and apply to deal with a class of fuzzy intergral equations in the best condition.

Functional Analysis · Mathematics 2017-07-10 Tran Minh Thuyet , Do Huy Hoang , Pham Thanh Son , Ho Quang Duc

An improvement of the author's result, proved in 1961, concerning necessary and sufficient conditions for the compactness of an imbedding operator is given.

Functional Analysis · Mathematics 2007-05-23 A. G. Ramm

Differential completions and compactifications of differential spaces are introduced and investigated. The existence of the maximal differential completion and the maximal differential compactification is proved. A sufficient condition for…

Differential Geometry · Mathematics 2011-03-30 Diana Dziewa-Dawidczyk , Zbigniew Pasternak-Winiarski

To appear in J. Funct. Spaces and Appl.

Functional Analysis · Mathematics 2008-06-27 Pascal Lefevre , Daniel Li , Herve Queffelec , Luis Rodriguez-Piazzaa

We state several sufficient conditions for compact spacelike surface in the3-dimensional de Sitter space to be totally geodesic or spherical.

Differential Geometry · Mathematics 2007-05-23 Alexander Borisenko

An improvement of the author's result, proved in 1961, concerning necessary and sufficient conditions for the compactness of embedding operators is given. A counterexample to a published statement concerning compactness of embedding…

Numerical Analysis · Mathematics 2007-05-23 A. G. Ramm

A version of Arzel\`a-Ascoli theorem for $X$ being $\sigma$-locally compact Hausdorff space is proved. The result is used in proving compactness of Fredholm, Hammerstein and Urysohn operators. Two fixed point theorems, for Hammerstein and…

Functional Analysis · Mathematics 2015-05-12 Mateusz Krukowski , Bogdan Przeradzki

We employ Schauder fixed-point Theorem to prove the existence of at least one positive continuous solution of the quadratic integral equation Moreover, the maximal and the minimal solutions of the last equation are also proved.

Classical Analysis and ODEs · Mathematics 2021-11-17 Insaf F. Ben Saouda , Haitham A. Makhzoumb , Kheria M. Msaikc

The classical criterion for compactness in Banach spaces of functions can be reformulated into a simple tightness condition in the time-frequency domain. This description preserves more explicitly the symmetry between time and frequency…

Functional Analysis · Mathematics 2007-05-23 Monika Dörfler , Hans G. Feichtinger , Karlheinz Gröchenig

We prove a compactness criterion for asymptotic $L_p$ spaces over arbitrary measure spaces. Total boundedness is characterized by almost equiboundedness together with total boundedness in $L_p$ of all truncations. This gives a…

Functional Analysis · Mathematics 2026-04-22 Nuno J. Alves

The paper discusses an applicability criterion for a cutoff regularization in the coordinate representation in the Euclidean space with a dimension larger than two. It is shown that the set of functions satisfying the criterion is not…

Mathematical Physics · Physics 2024-03-15 A. V. Ivanov

In this note a criterion for Cauchy sequences is proved which refines the one presented in `Cauchy sequences in b-metric spaces', Topology Appl. 373 (2025) 109477.

General Topology · Mathematics 2026-04-17 Lech Pasicki

We show that any set of quotients with fixed Chern classes of a given coherent sheaf on a compact Kaehler manifold is bounded in a sense which we define. The result is proved by adapting Grothendieck's boundedness criterium expressed via…

Complex Variables · Mathematics 2017-08-23 Matei Toma

It is shown that a specific ordering of the Rademacher chaos leads to a basic sequence in a wide class of symmetric spaces on the segment [0,1]. Necessary and sufficient conditions on a such space are found for Rademacher chaos to possess…

Functional Analysis · Mathematics 2007-05-23 S. V. Astashkin

In this article we introduce a new scale of weighted Orlicz-Sobolev sequence spaces generated by a class of suitable Orlicz functions and prove various continuity and compactness criteria for them. In a nutshell, continuity is a consequence…

Functional Analysis · Mathematics 2025-03-26 Pierre-A. Vuillermot

The aim of the paper is to characterize (pre)compactness in the spaces of Lipschitz/H\"older continuous mappings acting from a compact metric space to a normed space. To this end some extensions and generalizations of already existing…

Functional Analysis · Mathematics 2023-06-21 Jacek Gulgowski , Piotr Kasprzak , Piotr Maćkowiak

We prove a compactness theorem for metrics with Bounded Integral Curvature on a fixed closed surface $\Sigma$. As a corollary, we obtain a compactification of the space of Riemannian metrics with conical singularities, where an accumulation…

Differential Geometry · Mathematics 2016-10-20 Clément Debin

We give a sufficient condition for a composition operator with positive characteristic to be compact on the Hardy space of Dirichlet series.

Functional Analysis · Mathematics 2024-02-21 Frédéric Bayart

Necessary and sufficient conditions are given for the existence of extended Schmidt decompositions, with more than two subspaces.

Quantum Physics · Physics 2009-10-28 Asher Peres

The analog of the Schauder inequality for closed surfaces in Euclidean spaces is obtained in this article.

Differential Geometry · Mathematics 2007-06-18 Andrei Bodrenko
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