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We prove that every recurrent graph $G$ quasi-isometric to $\mathbb{R}$ admits an essentially unique Lipschitz harmonic function $h$. If $G$ is vertex-transitive, then the action of $Aut(G)$ preserves $\partial h$ up to a sign, a fact that…

Combinatorics · Mathematics 2023-04-27 Agelos Georgakopoulos , Alex Wendland

We investigate functionals defined on manifolds through parameterizations. If they are to be meaningful, from a geometrical viewpoint, they ought to be invariant under reparameterizations. Standard, local, integral functionals with this…

Differential Geometry · Mathematics 2024-11-08 Pablo Pedregal

The ring operations and the metric on $C(X)$ are extended to the set $\mathbb{H}_{nf}(X)$ of all nearly finite Hausdorff continuous interval valued functions and it is shown that $\mathbb{H}_{nf}(X)$ is both rationally and topologically…

Rings and Algebras · Mathematics 2007-12-05 Roumen Anguelov

We discuss, via a version of the Birkhoff-Kellogg theorem, the existence of positive and negative eigenvalues of Hammerstein integral equations with sign-changing nonlinearities and functional terms. The corresponding eigenfunctions have a…

Classical Analysis and ODEs · Mathematics 2025-07-08 Gennaro Infante , Giuseppe Antonio Veltri

Counterexamples show that many results in the geometric function theory of one complex variable are not applicable for several complex variables. In this paper, we obtain sharp bounds for the Zalcman functional for $n=3$ associated with the…

Complex Variables · Mathematics 2026-01-30 Surya Giri

In this paper we collect several examples of convergence of functions of random processes to generalized functionals of those processes. We remark that the limit is always finitely absolutely continuous with respect to Wiener measure. We…

Probability · Mathematics 2024-09-17 A. A. Dorogovtsev , Naoufel Salhi

A strong submeasure on a compact metric space X is a sub-linear and bounded operator on the space of continuous functions on X. A strong submeasure is positive if it is non-decreasing. By Hahn-Banach theorem, a positive strong submeasure is…

Dynamical Systems · Mathematics 2019-01-11 Tuyen Trung Truong

The concept of b-linear functional and its different types of continuity in linear n-normed space are presented and some of their properties are being established. We derive the Uniform Boundedness Principle and Hahn-Banach extension…

Functional Analysis · Mathematics 2021-10-26 Prasenjit Ghosh , T. K. Samanta

Motivated by the work of Baronti et al. [J. Math. Anal. Appl. 252(2000) 124-146], where they defined the supremum of an arithmetic mean of the side lengths of a triangle, summing antipodal points on the unit sphere, we introduce a new…

Functional Analysis · Mathematics 2026-01-01 Kallal Pal , Sumit Chandok

In the sub-Riemannian Heisenberg group equipped with its Carnot-Caratheodory metric and with a Haar measure, we consider isodiametric sets, i.e. sets maximizing the measure among all sets with a given diameter. In particular, given an…

Metric Geometry · Mathematics 2010-10-07 Gian Paolo Leonardi , Severine Rigot , Davide Vittone

The standard arithmetic measures of center, the mean and median, have natural topological counterparts which have been widely used in continuum theory. In the context of metric spaces it is natural to consider the Lipschitz continuous…

Metric Geometry · Mathematics 2024-06-19 Leonid V. Kovalev

We study coarea inequalities for metric surfaces -- metric spaces that are topological surfaces, without boundary, and which have locally finite Hausdorff 2-measure $\mathcal{H}^2$. For monotone Sobolev functions $u\colon X \to \mathbb{R}…

Metric Geometry · Mathematics 2022-08-15 Behnam Esmayli , Toni Ikonen , Kai Rajala

We consider functions with an asymptotic mean value property, known to characterize harmonicity in Riemannian manifolds, in doubling metric measure spaces. We show that the strongly amv-harmonic functions are H\"older continuous for any…

Analysis of PDEs · Mathematics 2023-01-18 Tomasz Adamowicz , Antoni Kijowski , Elefterios Soultanis

We apply thermodynamic formalism to a generalized horseshoe map. We prove that a tailored anisotropic Banach space with weighted norms yields a spectral gap for the transfer operator, implying the existence of a unique physical measure.…

Dynamical Systems · Mathematics 2026-01-06 Abbas Fakhari , Mohammad Soufi

The $\Gamma$-limit for a sequence of length functionals associated with a one parameter family of Riemannian manifolds is computed analytically. The Riemannian manifold is of `two-phase' type, that is, the metric coefficient takes values in…

Analysis of PDEs · Mathematics 2014-01-10 Hartmut Schwetlick , Daniel C. Sutton , Johannes Zimmer

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

Let $f: M\rightarrow M$ be a continuous map on a compact metric space $M$ equipped with a fixed metric $d$, and let $\tau$ be the topology on $M$ induced by $d$. First, we will establish some fundamental properties of the mean Hausdorff…

Dynamical Systems · Mathematics 2024-07-12 Jeovanny Muentes Acevedo , Alex Jenaro Becker , Alexandre Tavares Baraviera , Érick Scopel

We consider finitely generated group endowed with a word metric. The group acts on itself by isometries, which induces an action on its horofunction boundary. The conjecture is that nilpotent groups act trivially on their reduced boundary.…

Group Theory · Mathematics 2019-04-26 Uri Bader , Vladimir Finkelshtein

In this article, we mainly obtain the Riemann-Hurwitz theorems for harmonic morphisms on (vertex-weighted) metric graphs or metrized complexes of algebraic curves, inspired of the recent work on harmonic morphisms of graphs or metrized…

Algebraic Geometry · Mathematics 2022-01-13 Tingbin Cao , Mengnan Cheng

In this paper, we extend the Banach contraction principle to metric-like as well as partial metric spaces (not essentially complete) equipped with an arbitrary binary relation. Thereafter, we derive some fixed point results which are…

General Mathematics · Mathematics 2016-12-19 Md Ahmadullah , Abdur Rauf Khan , Mohammad Imdad