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Related papers: Weakly strongly regular uniform algebras

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The general theme of this note is illustrated by the following theorem: Theorem 1. Suppose $K$ is a compact set in the complex plane and 0 belongs to the boundary $\partial K$. Let ${\cal A}(K)$ denote the space of all functions $f$ on $K$…

Functional Analysis · Mathematics 2016-09-07 N. V. Rao

It is shown that there exists a compact planar set K such that the uniform algebra R(K) is nontrivial and strongly regular. This settles an issue raised by Donald Wilken 55 years ago. It is shown that the set K can be chosen such that, in…

Complex Variables · Mathematics 2025-01-03 Alexander J. Izzo

It is shown that there exists a compact set $X$ in ${\bf C}^N$ ($N\geq 2$) such that $\widehat X\setminus X$ is nonempty and the uniform algebra $P(X)$ has a dense set of invertible elements, a large Gleason part, and an abundance of…

Complex Variables · Mathematics 2016-06-21 Alexander J. Izzo

A singular riemannian foliation F on a complete riemannian manifold M is said to admit sections if each regular point of M is contained in a complete totally geodesic immersed submanifold (a section) that meets every leaf of F orthogonally…

Geometric Topology · Mathematics 2011-06-21 Marcos Alexandrino , Claudio Gorodski

Let $X$ and $Y$ be separable Banach spaces. Suppose $Y$ either has a shrinking basis or $Y$ is isomorphic to $C(2^\mathbb{N})$ and $A$ is a subset of weakly compact operators from $X$ to $Y$ which is analytic in the strong operator…

Functional Analysis · Mathematics 2013-04-15 Kevin Beanland , Daniel Freeman

We establish spherical variants of the Gleason-Kahane-Zelazko and Kowalski-S{\l}odkowski theorems, and we apply them to prove that every weak-2-local isometry between two uniform algebras is a linear map. Among the consequences, we solve a…

Functional Analysis · Mathematics 2017-05-11 Lei Li , Antonio M. Peralta , Liguang Wang , Ya-Shu Wang

In this paper, the concept of weakly uniform perfectness is considered. As an analogue of the theory of uniform perfectness, we obtain the relationships between weakly uniform perfectness and Bergman kernel, Poincar\'e metric and Hausdorff…

Complex Variables · Mathematics 2025-09-01 Zhiyuan Zheng

It is proved that the space of differential forms with weak exterior and co-derivative, is compactly embedded into the space of square integrable differential forms. Mixed boundary conditions on weak Lipschitz domains are considered.…

Analysis of PDEs · Mathematics 2019-05-01 Sebastian Bauer , Dirk Pauly , Michael Schomburg

We show how multiplier ideals can be used to obtain uniform multiplicative bounds for certain families of ideals on a smooth complex algebraic variety. In particular we prove a quick but rather surprising result about symbolic powers of…

Algebraic Geometry · Mathematics 2009-10-31 Lawrence Ein , Robert Lazarsfeld , Karen E. Smith

In this work we prove that if $X$ is a complete locally convex space and $f:X\to \mathbb{R}\cup \{+\infty \}$ is a function such that $f-x^\ast$ attains its minimum for every $x^\ast \in U$, where $U$ is an open set with respect to the…

Functional Analysis · Mathematics 2020-03-03 Pedro Pérez-Aros , Lionel Thibaul

We give a counterexample to a conjecture of S.E. Morris by showing that there is a compact plane set X such that R(X) has no non-zero, bounded point derivations but such that R(X) is not weakly amenable. We also give an example of a…

Functional Analysis · Mathematics 2007-05-23 J. F. Feinstein

We show that for any positive forward density subset N \subset Z, there exists an integer m>0, such that, for all n>m, N contains almost perfect n-scaled reproductions of any previously chosen finite set of integers.

Number Theory · Mathematics 2014-03-17 Mario Bessa , Maria Carvalho

We show that a finite set of integers $A \subseteq \mathbb{Z}$ with $|A+A| \le K |A|$ contains a large piece $X \subseteq A$ with Fre\u{i}man dimension $O(\log K)$, where large means $|A|/|X| \ll \exp(O(\log^2 K))$. This can be thought of…

Combinatorics · Mathematics 2016-06-06 Freddie Manners

We consider operators T : M_0 -> Z and T : M -> Z, where Z is a Banach space and (M_0, M) is a pair of Banach spaces belonging to a general construction in which M is defined by a "big-O" condition and M_0 is given by the corresponding…

Functional Analysis · Mathematics 2016-11-14 Karl-Mikael Perfekt

A cohomological vanishing property is proved for finitely supported ideals in an arbitrary d-dimensional regular local ring. (Such vanishing implies some refined Briancon-Skoda-type results, not otherwise known in mixed characteristic.) It…

Commutative Algebra · Mathematics 2007-05-23 Joseph Lipman

We introduce a vector-valued version of a uniform algebra, called the vector-valued function space over a uniform algebra. The diameter two properties of the vector-valued function space over a uniform algebra on an infinite compact…

Functional Analysis · Mathematics 2021-03-17 Han Ju Lee , Hyung-Joon Tag

Let $X$ be a pointed compact metric space. Assuming that $\mathrm{lip}_0(X)$ has the uniform separation property, we prove that every weakly compact composition operator on spaces of Lipschitz functions $\mathrm{Lip}_0(X)$ and…

Functional Analysis · Mathematics 2014-05-19 A. Jiménez-Vargas

Let $1\le m<n$ be integers, and let $K\subset\mathbb{R}^{n}$ be a self-similar set satisfying the strong separation condition, and with $\dim K=s>m$. We study the a.s. values of the $s-m$-dimensional Hausdorff and packing measures of $K\cap…

Dynamical Systems · Mathematics 2017-03-31 Ariel Rapaport

In a previous paper the second author introduced a compact topology on the space of closed ideals of a unital Banach algebra A. If A is separable then this topology is either metrizable or else neither Hausdorff nor first countable. Here it…

Functional Analysis · Mathematics 2007-05-23 J. F. Feinstein , D. W. B. Somerset

The purpose of this paper is to prove the following theorem of uniform Artin-Rees properties: Let $A$ be an excellent (in fact J-2) ring and let $N\subset M$ be two finitely generated $A$-modules such that ${\rm dim}(M/N)\leq 1$. Then there…

Commutative Algebra · Mathematics 2007-05-23 Francesc Planas-Vilanova