English
Related papers

Related papers: On dense subspaces in a class of Fr\'echet functio…

200 papers

Let $A$ be a simple algebra over a field $F$. Under a mild cardinality assumption on $F$, we determine the greatest possible dimension for an $F$-affine subspace of $A$ that is included in the group of units $A^\times$, and we describe the…

Rings and Algebras · Mathematics 2026-05-07 Clément de Seguins Pazzis

We study the subspaces of $L_p(\mathbb{R}^d)$ that consist of functions whose Fourier transforms vanish on a smooth surface of codimension $1$. We show that a subspace defined in such a manner coincides with the whole $L_p$ space for $p >…

Classical Analysis and ODEs · Mathematics 2016-01-26 Dmitriy M. Stolyarov

We present a rigorous convergence analysis for cylindrical approximations of nonlinear functionals, functional derivatives, and functional differential equations (FDEs). The purpose of this analysis is twofold: first, we prove that…

Numerical Analysis · Mathematics 2021-03-17 Daniele Venturi , Alec Dektor

The classical theorem of Bishop-Phelps asserts that, for a Banach space X, the norm-achieving functionals in X* are dense in X*. Bela Bollobas's extension of the theorem gives a quantitative description of just how dense the norm-achieving…

Functional Analysis · Mathematics 2013-07-31 Charles John Read

For a closure space (P,f) with f(\emptyset)=\emptyset, the closures of open subsets of P, called the regular closed subsets, form an ortholattice Reg(P,f), extending the poset Clop(P,f) of all clopen subsets. If (P,f) is a finite convex…

Combinatorics · Mathematics 2013-07-08 Luigi Santocanale , Friedrich Wehrung

We investigate the space $X$ of unitary hermitian matrices over $\frp$-adic fields through spherical functions. First we consider Cartan decomposition of $X$, and give precise representatives for fields with odd residual characteristic,…

Number Theory · Mathematics 2013-09-10 Yumiko Hironaka , Yasushi Komori

We show that affine subspaces of Euclidean space are of Khintchine type for divergence under certain multiplicative Diophantine conditions on the parametrizing matrix. This provides evidence towards the conjecture that all affine subspaces…

Number Theory · Mathematics 2020-02-18 Daniel C. Alvey

The functional (de)composition of polynomials is a topic in pure and computer algebra with many applications. The structure of decompositions of (suitably normalized) polynomials f(x) = g(h(x)) in F[x] over a field F is well understood in…

Symbolic Computation · Computer Science 2020-01-01 Joachim von zur Gathen , Mark Giesbrecht , Konstantin Ziegler

We prove that, if f:R^n\to R satisfies Fr\'echet's functional equation and f(x_1,...,x_n) is not an ordinary algebraic polynomial in the variables x_1,...,x_n, then f is unbounded on all non-empty open set U of R^n. Furthermore, the closure…

Classical Analysis and ODEs · Mathematics 2014-01-21 J. M. Almira , Kh. F. Abu-Helaiel

The aim of this paper is to to show the admissibility of some class of Frechet spaces (see Definition 2.3). In particular, this generalizes the main results of [3]. As an application, we show the admissibility of a large class modular…

Functional Analysis · Mathematics 2021-12-02 Maciej Ciesielski , Grzegorz Lewicki

Large algebraic structures are found inside the space of sequences of continuous functions on a compact interval having the property that, the series defined by each sequence converges absolutely and uniformly on the interval but the series…

Functional Analysis · Mathematics 2020-05-29 M. Carmen Calderón-Moreno , Pablo J. Gerlach-Mena , José A. Prado-Bassas

We develop a wavelet like representation of functions in $L^p(\mathbb{R})$ based on their Fourier--Hermite coefficients; i.e., we describe an expansion of such functions where the local behavior of the terms characterize completely the…

Classical Analysis and ODEs · Mathematics 2016-08-08 H. N. Mhaskar

The Riemann -Rock theorem plays a central role in the theory of Riemann surfaces with applications to several branches in Mathematics and Physics. Suppose $X$ ia a compact Riemann surface of genus $g$ and $P \in X$. By the Riemann-Roch…

Complex Variables · Mathematics 2025-02-21 V V Hemasundar Gollakota

This article studies descent theory in the setting of Berkovich spaces. We give sufficient conditions for a given fibered category over the category of k-affinoid algebras to be a stack for the Berkovich analogue of the faithfully-flat…

Algebraic Geometry · Mathematics 2023-01-11 Mathieu Daylies

We prove a version of the Bernstein-Walsh theorem on uniform polynomial approximation of holomorphic functions on compact sets in several complex variables. Here we consider subclasses of the full polynomial space associated to a convex…

Complex Variables · Mathematics 2017-01-23 Len Bos , Norm Levenberg

Matrix type operators with the off-diagonal decay of polynomial or sub-exponential types are revisited with weaker assumptions concerning row or column estimates, still giving the continuity results for the frame type operators. Such…

Functional Analysis · Mathematics 2019-07-03 Stevan Pilipović , Diana T. Stoeva

In this work, we prove some trace theorems for function spaces with a nonlocal character that contain the classical $W^{s,p}$ space as a subspace. The result we obtain generalizes well known trace theorems for $W^{s,p}(\Omega)$ functions…

Analysis of PDEs · Mathematics 2021-11-23 Qiang Du , Tadele Mengesha , Xiaochuan Tian

Known results about hypercyclic subspaces concern either Fr\'echet spaces with a continuous norm or the space \omega. We fill the gap between these spaces by investigating Fr\'echet spaces without continuous norm. To this end, we divide…

Dynamical Systems · Mathematics 2013-12-02 Quentin Menet

In this note we study Banach spaces of traces of real polynomials on $\mathbb R^n$ to compact subsets equipped with supremum norms from the point of view of Geometric Functional Analysis.

Functional Analysis · Mathematics 2014-04-23 Alexander Brudnyi

It has been found empirically that quasi-Monte Carlo methods are often efficient for very high-dimensional problems, that is, with dimension in the hundreds or even thousands. The common explanation for this surprising fact is that those…

Numerical Analysis · Mathematics 2014-09-23 Christian Irrgeher , Gunther Leobacher