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Related papers: Using boundaries to find smooth norms

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We introduce a new isomorphic quantity for Banach spaces, the index $\Theta_X$, based on finite convex coverings of the unit ball. This index is closely related to the asymptotic moduli of uniform convexity and uniform smoothness, so that…

Functional Analysis · Mathematics 2025-11-11 Matias Raja

We introduce the notion of approximate smoothness in a normed linear space. We characterize this property and show the connections between smoothness and approximate smoothness for some spaces. As an application, we consider in particular…

Functional Analysis · Mathematics 2022-11-08 Jacek Chmieliński , Divya Khurana , Debmalya Sain

In this note the result by A. Swift concerning the embeddability of countably branching bundle graphs into Banach spaces is extended from the context of reflexive spaces with an unconditional asymptotic structure to the context of dual…

Functional Analysis · Mathematics 2021-04-22 Yoël Perreau

The authors study Tikhonov regularization of linear ill-posed problems with a general convex penalty defined on a Banach space. It is well known that the error analysis requires smoothness assumptions. Here such assumptions are given in…

Numerical Analysis · Mathematics 2019-08-19 Bernd Hofmann , Stefan Kindermann , Peter Mathé

In this article, we characterize the $UMD$--property of a Banach space $X$ by ideal norms associated with trigonometric orthonormal systems. The asymptotic behavior of that numerical parameters can be used to decide whether or not $X$ is a…

Functional Analysis · Mathematics 2016-09-06 Joerg Wenzel

We provide sufficient conditions for a mapping between two Banach spaces to be a diffeomorphism using the approach of an auxiliary functional and also by the aid of a duality mapping corresponding to a normalization function. We simplify…

Functional Analysis · Mathematics 2018-09-17 Marek Galewski , Dušan Repovš

We show that for any uniformly elliptic fully nonlinear second-order equation with bounded measurable "coefficients" and bounded "free" term one can find an approximating equation which has a unique continuous and having the second…

Analysis of PDEs · Mathematics 2012-04-03 N. V. Krylov

There are presented certain results on extending continuous linear operators defined on spaces of E-valued continuous functions (defined on a compact Hausdorff space X) to linear operators defined on spaces of E-valued measurable functions…

Functional Analysis · Mathematics 2017-05-26 Piotr Niemiec

The main objective of this article is to provide an alternative approach to the central result of [Eldred, A. Anthony, Kirk, W. A., Veeramani, P., Proximal normal structure and relatively nonexpansive mappings, Studia Math., vol 171(3),…

Functional Analysis · Mathematics 2022-06-30 Abhik Digar , G. Sankara Raju Kosuru

The paper is concerned with the problem whether a nonseparable Banach space must contain an uncountable set of vectors such that the distances between every two distinct vectors of the set are the same. Such sets are called equilateral. We…

Functional Analysis · Mathematics 2015-04-21 Piotr Koszmider

We prove that (a) the sections space of a continuous unital subhomogeneous $C^*$ bundle over compact metrizable $X$ admits a finite-index expectation onto $C(X)$, answering a question of Blanchard-Gogi\'{c} (in the metrizable case); (b)…

Operator Algebras · Mathematics 2025-11-04 Alexandru Chirvasitu

We study two notions of approximate Birkhoff-James orthogonality in a normed space, from a geometric point of view, and characterize them in terms of normal cones. We further explore the interconnection between normal cones and approximate…

Functional Analysis · Mathematics 2024-07-30 Debmalya Sain , Kallol Paul , Arpita mal

In this paper, we begin by constructing global linear maps on (n-2)-dimensional subspaces, derived from the local continuity of linear transformations among central sections of a convex body. Using these linear maps, we subsequently…

Functional Analysis · Mathematics 2026-04-07 Ning Zhang

In this paper we relate the geometry of Banach spaces to the theory of differential equations, apparently in a new way. We will construct Banach function space norms arising as weak solutions to ordinary differential equations of first…

Functional Analysis · Mathematics 2016-08-30 Jarno Talponen

We continue our study of the free boundary regularity in the thin one-phase problem and show that $C^{2,\alpha}$ free boundaries are smooth.

Analysis of PDEs · Mathematics 2014-02-06 Daniela De Silva , Ovidiu Savin

We prove that, given any covering of any separable infinite-dimensional uniformly rotund and uniformly smooth Banach space $X$ by closed balls each of positive radius, some point exists in $X$ which belongs to infinitely many balls.

Functional Analysis · Mathematics 2012-12-13 Vladimir P. Fonf , Michael Levin , Clemente Zanco

We modify the very well known theory of normed spaces $(E, \norm)$ within functional analysis by considering a sequence $(\norm_n : n\in\N)$ of norms, where $\norm_n$ is defined on the product space $E^n$ for each $n\in\N$. Our theory is…

Functional Analysis · Mathematics 2012-03-20 H. G. Dales , M. E. Polyakov

The main purpose of this paper is to give a general regularity result for Cauchy-Riemann equations in complex Banach spaces with totally real boundary conditions. The usual elliptic $L^p$-regularity results hold true under one crucial…

Analysis of PDEs · Mathematics 2007-05-23 Katrin Wehrheim

We show that if $X$ is a Banach space whose dual $X^{*}$ has an equivalent locally uniformly rotund (LUR) norm, then for every open convex $U\subseteq X$, for every $\varepsilon >0$, and for every continuous and convex function $f:U…

Functional Analysis · Mathematics 2014-11-04 Daniel Azagra , Carlos Mudarra

In this paper, we give sufficient conditions to establish central limit theorems for boundary estimates of Poisson point processes. The considered estimates are obtained by smoothing some bias corrected extreme values of the point process.…

Statistics Theory · Mathematics 2011-03-31 Stéphane Girard , Ludovic Menneteau