Results 31 to 40 of about 11,694 (136)
On the extension of linear operators
International Journal of Mathematics and Mathematical Sciences, 2001 It is well known that the Hahn-Banach theorem, that is, the extension theorem for bounded linear functionals, is not true in general for bounded linear operators. A characterization of spaces for which it is true was published by Kakutani in 1940.
John J. Saccoman
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ℂ-convexity in infinite-dimensional Banach spaces and applications to Kergin interpolation
International Journal of Mathematics and Mathematical Sciences, 2006 We investigate the concepts of linear convexity and ℂ-convexity in complex Banach spaces. The main result is that any ℂ-convex domain is necessarily linearly convex.
Lars Filipsson
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On Four Classical Measure Theorems
Mathematics, 2021 A subset B of an algebra A of subsets of a set Ω has property (N) if each B-pointwise bounded sequence of the Banach space ba(A) is bounded in ba(A), where ba(A) is the Banach space of real or complex bounded finitely additive measures defined on A ...
Salvador López-Alfonso +2 more
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Generalized Integral Transforms via the Series Expressions
Mathematics, 2020 From the change of variable formula on the Wiener space, we calculate various integral transforms for functionals on the Wiener space. However, not all functionals can be obtained by using this formula.
Hyun Soo Chung
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Polynomial Approximation on Unbounded Subsets, Markov Moment Problem and Other Applications
Mathematics, 2020 This paper starts by recalling the author’s results on polynomial approximation over a Cartesian product A of closed unbounded intervals and its applications to solving Markov moment problems.
Octav Olteanu
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Potential trace inequalities via a Calderón‐type theorem
Journal of the London Mathematical Society, Volume 113, Issue 3, March 2026.Abstract In this paper, we develop a general theoretical tool for the establishment of the boundedness of notoriously difficult operators (such as potentials) on certain specific types of rearrangement‐invariant function spaces from analogous properties of operators that are easier to handle (such as fractional maximal operators).
Zdeněk Mihula +2 more
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A Version of the Hahn-Banach Theorem for R-Vector Spaces [PDF]
Sahand Communications in Mathematical AnalysisRecently, $R$-metric spaces have been introduced to generalized metric spaces. This extension is based on the construction of a new universe with interesting properties.
Azadeh Alijani +2 more
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The asymmetric sandwich theorem
, 2011 We discuss the asymmetric sandwich theorem, a generalization of the Hahn-Banach theorem. As applications, we derive various results on the existence of linear functionals that include bivariate, trivariate and quadrivariate generalizations of the Fenchel
Galin L. A. +5 more
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Solvability of invariant systems of differential equations on H2$\mathbb {H}^2$ and beyond
Mathematische Nachrichten, Volume 299, Issue 2, Page 456-479, February 2026.Abstract We show how the Fourier transform for distributional sections of vector bundles over symmetric spaces of non‐compact type G/K$G/K$ can be used for questions of solvability of systems of invariant differential equations in analogy to Hörmander's proof of the Ehrenpreis–Malgrange theorem.
Martin Olbrich, Guendalina Palmirotta
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A Choquet theory of Lipschitz‐free spaces
Proceedings of the London Mathematical Society, Volume 132, Issue 2, February 2026.Abstract Let (M,d)$(M,d)$ be a complete metric space and let F(M)$\mathcal {F}({M})$ denote the Lipschitz‐free space over M$M$. We develop a ‘Choquet theory of Lipschitz‐free spaces’ that draws from the classical Choquet theory and the De Leeuw representation of elements of F(M)$\mathcal {F}({M})$ (and its bi‐dual) by positive Radon measures on βM ...
Richard J. Smith
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