Results 51 to 60 of about 11,746 (180)
Quantitative Hahn-Banach Theorems and Isometric Extensions forWavelet and Other Banach Spaces
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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Superlinear perturbations of a double‐phase eigenvalue problem
Transactions of the London Mathematical Society, Volume 12, Issue 1, December 2025.Abstract We consider a perturbed version of an eigenvalue problem for the double‐phase operator. The perturbation is superlinear, but need not satisfy the Ambrosetti–Robinowitz condition. Working on the Sobolev–Orlicz space W01,η(Ω)$ W^{1,\eta }_{0}(\Omega)$ with η(z,t)=α(z)tp+tq$ \eta (z,t)=\alpha (z)t^{p}+t^{q}$ for 1
Yunru Bai +2 more
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On peak phenomena for non-commutative $H^\infty$
, 2008 A non-commutative extension of Amar and Lederer's peak set result is given. As its simple applications it is shown that any non-commutative $H^\infty$-algebra $H^\infty(M,\tau)$ has unique predual,and moreover some restriction in some of the results of ...
A. Grothendieck +27 more
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The domination theorem for operator classes generated by Orlicz spaces
Mathematische Nachrichten, Volume 298, Issue 11, Page 3576-3598, November 2025.Abstract We study lattice summing operators between Banach spaces focusing on two classes, ℓφ$\ell _\varphi$‐summing and strongly φ$\varphi$‐summing operators, which are generated by Orlicz sequence lattices ℓφ$\ell _\varphi$. For the class of strongly φ$\varphi$‐summing operators, we prove the domination theorem, which complements Pietsch's ...
D. L. Fernandez +3 more
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Uniform approximation of continuous functions by smooth functions with no critical points on Hilbert manifolds [PDF]
, 2001 We prove that every continuous function on a separable infinite-dimensional Hilbert space X can be uniformly approximated by smooth functions with no critical points. This kind of result can be regarded as a sort of very strong approximate version of the
Azagra, Daniel, Boiso, Manuel Cepedello
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Existence of Weak Solutions for a Degenerate Goursat‐Type Linear Problem
Mathematical Methods in the Applied Sciences, Volume 48, Issue 15, Page 14334-14341, October 2025.ABSTRACT For a generalization of the Gellerstedt operator with mixed‐type Dirichlet boundary conditions to a suitable Tricomi domain, we prove the existence and uniqueness of weak solutions of the linear problem and for a generalization of this problem.
Olimpio Hiroshi Miyagaki +2 more
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Factorizations and minimality of the Calkin Algebra norm for C(K)$C(K)$‐spaces
Journal of the London Mathematical Society, Volume 112, Issue 4, October 2025.Abstract For a scattered, locally compact Hausdorff space K$K$, we prove that the essential norm on the Calkin algebra B(C0(K))/K(C0(K))$\mathcal {B}(C_0(K))/\mathcal {K}(C_0(K))$ is a minimal algebra norm. The proof relies on establishing a quantitative factorization for the identity operator on c0$c_0$ through noncompact operators T:C0(K)→X$T: C_0(K)
Antonio Acuaviva
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A structural version of the theorem of Hahn-Banach [PDF]
, 2001 We consider one of the basic results of functional analysis, the classical theorem of Hahn-Banach. This theorem gives the existence of a continuous linear functional on a given normed vectorspace extending a given continuous linear functional on a ...
Brinkhuis, J. (Jan)
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Journal of Applied Econometrics, Volume 40, Issue 6, Page 608-626, September/October 2025.ABSTRACT This paper introduces a generalized model of peer effects for binary outcomes, based on a network game that accounts for strategic complementarity (influence of the number of peers that select the same action) and conformity to social norms (penalizing deviations from the average peers' action).
Mathieu Lambotte
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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.
openaire +2 more sources