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Related papers: Generalized Harmonic Functions on Trees: Universal…

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We show that the set of frequently universal harmonic functions on a tree T contains a vector space except 0 which is dense in the space of harmonic functions on T seen as subset of C^T . In order to prove this we replace the complex plane…

Functional Analysis · Mathematics 2019-08-27 N. Biehler , V. Nestoridis , A. Stavrianidi

It has been shown that the set of universal functions on trees contains a linear subspace except zero, dense in the space of harmonic functions. In this paper we show that the set of universal functions contains two linear subspaces except…

Functional Analysis · Mathematics 2022-10-19 C. A. Konidas , V. Nestoridis

It is well known that the set of universal functions on a tree contains a vector space except zero which is dense in the set of harmonic functions. In this paper we improve this result by proving that the set of universal functions on a…

Functional Analysis · Mathematics 2022-01-04 C. A. Konidas

We consider generalizations of classical function spaces by requiring that a holomorphic in ${\Omega}$ function satisfies some property when we approach from ${\Omega}$, not the whole boundary, but only a part of it. These spaces endowed…

Complex Variables · Mathematics 2018-05-21 Dimitris Lygkonis , Vassilis Nestoridis

The paper addresses the question whether a random functional, a map from a set $E$ into the space of real-valued measurable functions on a probability space, has a measurable version with values in ${\mathbb R}^E$. Similarly, one may ask…

Functional Analysis · Mathematics 2024-02-08 Michael Oberguggenberger

We prove the existence of harmonic functions $f$ on trees, with respect to suitable transient transition operators $P$, that satisfy an analogue of Menshov universal property in the following sense: $f$ is the Poisson transform of a…

Functional Analysis · Mathematics 2022-02-17 Evgeny Abakumov , Vassili Nestoridis , Massimo Picardello

The harmonic numbers and generalized harmonic numbers appear frequently in many diverse areas such as combinatorial problems, many expressions involving special functions in analytic number theory and analysis of algorithms. The aim of this…

Number Theory · Mathematics 2023-01-02 Dae san Kim , Hye Kyung Kim , Taekyun Kim

We introduce and study properties of certain new harmonic function spaces on products of upper half-spaces.Norm estimates for the so-called expanded Bergman projections are obtained.Sharp theorems on multipliers acting on certain Sobolev…

Functional Analysis · Mathematics 2012-01-18 Milos Arsenovic , Romi F. Shamoyan

In this paper we give some estimates for nonlinear harmonic measures on trees. In particular, we estimate in terms of the size of a set $D$ the value at the origin of the solution to $ u(x)=F((x,0),\dots,(x,m-1))$ for every…

Analysis of PDEs · Mathematics 2015-01-30 Leandro M. Del Pezzo , Carolina A. Mosquera , Julio D. Rossi

A function on a (generally infinite) graph $\G$ with values in a field $K$ of characteristic 2 will be called {\it harmonic} if its value at every vertex of $\G$ is the sum of its values over all adjacent vertices. We consider binary…

Mathematical Physics · Physics 2007-05-23 Mikhail Zaidenberg

Let P -> M be a principal G-bundle. Using techniques from the loop representation of gauge theory, we construct well-defined substitutes for ``Lebesgue measure'' on the space A of connections on P and for ``Haar measure'' on the group Ga of…

High Energy Physics - Theory · Physics 2009-10-22 John C. Baez

Motivated from the study of eccentricity, center, and sum of eccentricities in graphs and trees, we introduce several new distance-based global and local functions based on the smallest distance from a vertex to some leaf (called the…

Combinatorics · Mathematics 2019-01-30 Ya-Hong Chen , Hua Wang , Xiao-Dong Zhang

Based on Colombeau's theory of algebras of generalized functions we introduce the concepts of generalized functions taking values in differentiable manifolds as well as of generalized vector bundle homomorphisms. We study their basic…

Functional Analysis · Mathematics 2007-05-23 Michael Kunzinger

On a countable tree $T$, allowing vertices with infinite degree, we consider an arbitrary stochastic irreducible nearest neighbour transition operator $P$. We provide a boundary integral representation for general eigenfunctions of $P$ with…

Functional Analysis · Mathematics 2022-06-10 Massimo A. Picardello , Wolfgang Woess

In this pedagogically structured article, we describe a generalized harmonic formulation of the Einstein equations in spherical symmetry which is regular at the origin. The generalized harmonic approach has attracted significant attention…

General Relativity and Quantum Cosmology · Physics 2010-05-07 Evgeny Sorkin , Matthew W. Choptuik

One of the main virtues of trees is to represent formal solutions of various functional equations which can be cast in the form of fixed point problems. Basic examples include differential equations and functional (Lagrange) inversion in…

Combinatorics · Mathematics 2013-02-12 Florent Hivert , Jean-Christophe Novelli , Jean-Yves Thibon

We introduce a new class $\mathcal{FV}(\Omega,E)$ of spaces of weighted functions on a set $\Omega$ with values in a locally convex Hausdorff space $E$ which covers many classical spaces of vector-valued functions like continuous, smooth,…

Functional Analysis · Mathematics 2021-04-08 Karsten Kruse

Let $E\subset \mathbb{R}^{n+1}$, $n\ge 2$, be a uniformly rectifiable set of dimension $n$. Then bounded harmonic functions in $\Omega:= \mathbb{R}^{n+1}\setminus E$ satisfy Carleson measure estimates, and are "$\varepsilon$-approximable".…

Analysis of PDEs · Mathematics 2016-09-07 Steve Hofmann , Jose Maria Martell , Svitlana Mayboroda

Let $L(G)$ denote the space of integer-valued length functions on a countable group $G$ endowed with the topology of pointwise convergence. Assuming that $G$ does not satisfy any non-trivial mixed identity, we prove that a generic (in the…

Group Theory · Mathematics 2023-05-02 A. Jarnevic , D. Osin , K. Oyakawa

In recent works, arbitrary structural sets in the non-commutative Clifford analysis context have been used to introduce non-trivial generalizations of harmonic Clifford algebra valued functions in $\mathbb{R}^m$. Being defined as the…

Analysis of PDEs · Mathematics 2022-02-18 Daniel Alfonso Santiesteban , Yudier Peña Pérez , Ricardo Abreu Blaya
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