Results 21 to 30 of about 854 (144)
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
wiley +1 more source
Some extensions of a dual of the Hahn-Banach Theorem, with applications to separation and Helly type theorems [PDF]
Bulletin of the Australian Mathematical Society, 1976 In previous papers we have proved that if G is a ω*-closed subspace of the conjugate space B* of a normed linear space B, then every b ∈ B can be extended within B, from G to the whole B*, with an arbitrarily small increase of the norm. Here we give some extensions of this result to the case when B* is replaced by a normed linear space E and B by any ...
openaire +2 more sources
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
wiley +1 more source
Plank theorems and their applications: A survey
Bulletin of the London Mathematical Society, Volume 58, Issue 1, January 2026.Abstract Plank problems concern the covering of convex bodies by planks in Euclidean space and are related to famous open problems in convex geometry. In this survey, we introduce plank problems and present surprising applications of plank theorems in various areas of mathematics.
William Verreault
wiley +1 more source
On ℬ‐Analog of the Sumudu Transform Associated With the General Quantum ℬ‐Difference Operator
Journal of Mathematics, Volume 2026, Issue 1, 2026.We present here a B‐analog of the Sumudu transform defined via a general quantum B‐difference operator which generalizes classical difference operators in the context of quantum calculus, is employed to study the proposed problem. We explore the core characteristics of the B‐Sumudu transform and illustrate its applications in solving B‐initial value ...
Karima M. Oraby +2 more
wiley +1 more source
On the Borel Complexity of Hahn-Banach Extensions
, 2005 The classical Hahn-Banach Theorem states that any linear bounded functional defined on a linear subspace of a normed space admits a norm-preserving linear bounded extension to the whole space.
Brattka, Vasco
core +1 more source
Journal of Mathematics, Volume 2026, Issue 1, 2026.In this paper, we investigate the stability and numerical solution of second‐order linear nonhomogeneous equations with the general quantum B‐difference operator. We prove Hyers–Ulam stability (HU s) and Hyers–Ulam–Rassias stability (HUR s) for these equations using a Riccati equation approach and variation of parameters technique.
Karima M. Oraby +3 more
wiley +1 more source
A HAHN-BANACH EXTENSION THEOREM FOR ENTIRE FUNCTIONS OF NUCLEAR TYPE
Journal of the Korean Mathematical Society, 2004 Let \(E\) be a nuclear space and \(F\) be a Banach space, both over the complex numbers. Let \(f\) be a holomorphic map from \(E\) to \(F\). It is shown that \(f\) is of uniformly bounded type if and only if, for an arbitrary locally convex space \(G\) containing \(E\) as a closed subspace, \(f\) can be extended to a holomorphic map from \(F\) to \(G\).
openaire +3 more sources
Weak solutions for a singular beam equation
ZAMM - Journal of Applied Mathematics and Mechanics / Zeitschrift für Angewandte Mathematik und Mechanik, Volume 105, Issue 12, December 2025.Abstract This paper deals with a dynamic Gao beam of infinite length subjected to a moving concentrated Dirac mass. Under appropriate regularity assumptions on the initial data, the problem possesses a weak solution which is obtained as the limit of a sequence of solutions of regularized problems.
Olena Atlasiuk +2 more
wiley +1 more source
Conformal optimization of eigenvalues on surfaces with symmetries
Journal of the London Mathematical Society, Volume 112, Issue 6, December 2025.Abstract Given a conformal action of a discrete group on a Riemann surface, we study the maximization of Laplace and Steklov eigenvalues within a conformal class, considering metrics invariant under the group action. We establish natural conditions for the existence and regularity of maximizers. Our method simplifies the previously known techniques for
Denis Vinokurov
wiley +1 more source