Results 1 to 10 of about 7,951 (103)
McShane-Whitney extensions in constructive analysis [PDF]
Logical Methods in Computer Science, 2020 Within Bishop-style constructive mathematics we study the classical McShane-Whitney theorem on the extendability of real-valued Lipschitz functions defined on a subset of a metric space.
Iosif Petrakis
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The Hahn-Banach Extension Theorem for Fuzzy Normed Spaces Revisited [PDF]
Abstract and Applied Analysis, 2014 This paper deals with fuzzy normed spaces in the sense of Cheng and Mordeson. We characterize fuzzy norms in terms of ascending and separating families of seminorms and prove an extension theorem for continuous linear functionals on a fuzzy normed space.
Carmen Alegre, Salvador Romaguera
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Quantitative Hahn-Banach Theorems and Isometric Extensions forWavelet and Other Banach Spaces [PDF]
Axioms, 2013 We introduce and study Clarkson, Dol’nikov-Pichugov, Jacobi and mutual diameter constants reflecting the geometry of a Banach space and Clarkson, Jacobi and Pichugov classes of Banach spaces and their relations with James, self-Jung, Kottman and Schäffer
Sergey Ajiev
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Convexity, Markov Operators, Approximation, and Related Optimization
Mathematics, 2022 The present review paper provides recent results on convexity and its applications to the constrained extension of linear operators, motivated by the existence of subgradients of continuous convex operators, the Markov moment problem and related Markov ...
Octav Olteanu
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Mathematics, 2022 As is well-known, unlike the one-dimensional case, there exist nonnegative polynomials in several real variables that are not sums of squares. First, we briefly review a method of approximating any real-valued nonnegative continuous compactly supported ...
Octav Olteanu
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On Hahn-Banach theorem and some of its applications
Open Mathematics, 2022 First, this work provides an overview of some of the Hahn-Banach type theorems. Of note, some of these extension results for linear operators found recent applications to isotonicity of convex operators on a convex cone.
Olteanu Octav
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Mathematics, 2020 The aim of this review paper is to recall known solutions for two Markov moment problems, which can be formulated as Hahn–Banach extension theorems, in order to emphasize their relationship with the following problems: (1) pointing out a previously ...
Octav Olteanu
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Support theorems in abstract settings [PDF]
, 2017 In this paper we establish a general framework in which the verification of support theorems for generalized convex functions acting between an algebraic structure and an ordered algebraic structure is still possible.
Olbryś, Andrzej, Páles, Zsolt
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Unique Hahn-Banach extensions and Korovkin’s theorem [PDF]
Proceedings of the American Mathematical Society, 1975 This paper characterizes in terms of weak topologies those bounded linear functionals on a subspace which have unique Hahn-Banach extensions to the whole linear normed space. The relationship to the Choquet boundary is discussed, and a Korovkin type theorem is obtained.
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The Tracial Hahn-Banach Theorem, Polar Duals, Matrix Convex Sets, and Projections of Free Spectrahedra [PDF]
, 2016 This article investigates matrix convex sets and introduces their tracial analogs which we call contractively tracial convex sets. In both contexts completely positive (cp) maps play a central role: unital cp maps in the case of matrix convex sets and ...
Helton, J. William +2 more
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