English
Related papers

Related papers: Smooth analytic functions and model subspaces

200 papers

This paper studies the estimation of smooth functionals $f(\theta)$ of a mean parameter $\theta = \mathbb{E}_P[W]$ for a distribution $P$ on a general Banach space. We propose a cross-fitted estimator based on a single sample splitting and…

Statistics Theory · Mathematics 2026-04-03 Woonyoung Chang , Arun Kumar Kuchibhotla

Motivated by a problem in approximation theory, we find a necessary and sufficient condition for a model (backward shift invariant) subspace $K_\varTheta = H^2\ominus \varTheta H^2$ of the Hardy space $H^2$ to contain a bounded univalent…

Complex Variables · Mathematics 2017-06-07 Anton Baranov , Yurii Belov , Alexander Borichev , Konstantin Fedorovskiy

Looking for the universal covering of the smooth non-commutative torus leads to a curve of associative multiplications on the space $\Cal O_M'(\Bbb R^{2n})\cong \Cal O_C(\Bbb R^{2n})$ of Laurent Schwartz which is smooth in the deformation…

Quantum Algebra · Mathematics 2007-05-23 Michel Dubois-Violette , Andreas Kriegl , Yoshiaki Maeda , Peter W. Michor

The goal of the present paper is to introduce and study noncommutative Hardy spaces associated with the regular $\Lambda$-polyball, to develop a functional calculus on noncommutative Hardy spaces for the completely non-coisometric (c.n.c.)…

Functional Analysis · Mathematics 2020-01-31 Gelu Popescu

We investigate relations between symmetrizations of quasi-Banach function spaces and constructions such as Calderon-Lozanovskii spaces, pointwise product spaces and pointwise multipliers. We show that under reasonable assumptions the…

Functional Analysis · Mathematics 2018-01-18 Pawel Kolwicz , Karol Lesnik , Lech Maligranda

A topological space $X$ is called $\Cal A$-real compact, if every algebra homomorphism from $\Cal A$ to the reals is an evaluation at some point of $X$, where $\Cal A$ is an algebra of continuous functions. Our main interest lies on…

Functional Analysis · Mathematics 2016-09-06 Andreas Kriegl , Peter W. Michor

For $\lambda\ge0$, a $C^2$ function $f$ defined on the unit disk ${{\mathbb D}}$ is said to be $\lambda$-analytic if $D_{\bar{z}}f=0$, where $D_{\bar{z}}$ is the (complex) Dunkl operator given by…

Complex Variables · Mathematics 2023-07-04 Zhongkai Li , Haihua Wei

In this paper we investigate the approximation of continuous functions on the Wasserstein space by smooth functions, with smoothness meant in the sense of Lions differentiability. In particular, in the case of a Lipschitz function we are…

Probability · Mathematics 2023-08-14 Andrea Cosso , Mattia Martini

We introduce the Banach spaces $\ell^p_{a,b}$ and $c_{0,a,b}$, of analytic functions on the unit disc, having normalized Schauder bases consisting of polynomials of the form $f_n(z)=(a_n+b_nz)z^n, ~~n\geq0$, where $\{f_n\}$ is assumed to be…

Functional Analysis · Mathematics 2024-04-22 Bibhash Kumar Das , Aneesh Mundayadan

We introduce the notion of functionally compact sets into the theory of nonlinear generalized functions in the sense of Colombeau. The motivation behind our construction is to transfer, as far as possible, properties enjoyed by standard…

Functional Analysis · Mathematics 2016-03-01 Paolo Giordano , Michael Kunzinger

We construct valuations on the space of finite-valued convex functions using integration of differential forms over the differential cycle associated to a convex function. We describe the kernel of this procedure and show that the…

Metric Geometry · Mathematics 2021-10-18 Jonas Knoerr

Let $X$ be a ball quasi-Banach function space satisfying some mild assumptions and $H_X(\mathbb{R}^n)$ the Hardy space associated with $X$. In this article, the authors introduce both the Hardy space $H_X(\mathbb{R}^{n+1}_+)$ of harmonic…

Functional Analysis · Mathematics 2022-08-23 Fan Wang , Dachun Yang , Wen Yuan

Using tools and results from geometric measure theory, we give a simple new proof of the main result (Theorem 1.3) in K. Kondo and M. Tanaka, Approximation of Lipschitz Maps via Immersions and Differentiable Exotic Sphere Theorems,…

Differential Geometry · Mathematics 2019-04-02 Siran Li

These notes briefly consider some aspects of the Schwartz class of rapidly decreasing smooth functions, tempered distributions, and harmonic functions of polynomial growth.

Classical Analysis and ODEs · Mathematics 2007-05-23 Stephen Semmes

We describe recent nonlinear analytic approximation tools in the classical setting of Hardy spaces in the upper half plane and show how to transfer them to the higher dimensional real setting of harmonic functions in upper half spaces. It…

Classical Analysis and ODEs · Mathematics 2022-10-06 Ronald R. Coifman , Jacques Peyrière , Guido Weiss

For the class of de Branges-Rovnyak spaces $\mathcal{H}(b)$ of the unit disk $\mathbb{D}$ defined by extreme points $b$ of the unit ball of $H^\infty$, we study the problem of approximation of a general function in $\mathcal{H}(b)$ by a…

Functional Analysis · Mathematics 2021-08-20 Adem Limani , Bartosz Malman

We study weighted $H^\infty$ spaces of analytic functions on the open unit disc in the case of non-doubling weights, which decrease rapidly with respect to the boundary distance. We characterize the solid hulls of such spaces and give quite…

Functional Analysis · Mathematics 2017-02-02 José Bonet , Jari Taskinen

This current article aims to study a new subclass of meromorphic functions with positive coefficients by reconstructing a new operator in the punctured open disc. Also, some geometric properties are considered and investigated, such results…

Complex Variables · Mathematics 2024-08-16 Ali H. Maran , Abdul Rahman S. Juma , Raheam A. Al-Saphory

This paper provides a study of problems related to Hardy spaces left by G.\,Weiss in \cite{We}. First, We will prove that the Hardy spaces $H^p(\mathbb{R}^n)$ can be characterized by a fixed Lipschitz function.

Functional Analysis · Mathematics 2022-06-30 ZhuoRan Hu

Let $\mathcal{S}_H^0(K)$, $K\ge 1$, be the class of normalized $K$-quasiconformal harmonic mappings in the unit disk. We obtain Baernstein type extremal results for the analytic and co-analytic parts of functions in the geometric subclasses…

Complex Variables · Mathematics 2025-10-21 Suman Das , Jie Huang , Antti Rasila