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Non-autonomous self-similar sets are a family of compact sets which are, in some sense, highly homogeneous in space but highly inhomogeneous in scale. The main purpose of this note is to clarify various regularity properties and separation…

Dynamical Systems · Mathematics 2025-10-22 Antti Käenmäki , Alex Rutar

We prove a compactness criterion for asymptotic $L_p$ spaces over arbitrary measure spaces. Total boundedness is characterized by almost equiboundedness together with total boundedness in $L_p$ of all truncations. This gives a…

Functional Analysis · Mathematics 2026-04-22 Nuno J. Alves

Similar to linear spaces, many examples of quasilinear spaces have a notion of multiplication of the elements. To characterising these examples, in the present paper we generalize the notion of quasilinear spaces and introduce…

Functional Analysis · Mathematics 2020-10-20 Reza Dehghanizade , Seyed Mohamad Sadegh Modarres Mosadegh

To a generalized tight continuous frame in a Hilbert space $\H$ indexed by a locally compact space $\Si$ endowed with a Radon measure, one associates a coorbit theory converting spaces of functions on $\Si$ in spaces of vectors comparable…

Functional Analysis · Mathematics 2014-06-30 M. Mantoiu , D. Parra

We characterize Lipschitz morphisms between quantum compact metric spaces as those *-morphisms which preserve the domain of certain noncommutative analogues of Lipschitz seminorms, namely lower semi-continuous Lip-norms. As a corollary,…

Operator Algebras · Mathematics 2021-10-05 Frederic Latremoliere

Unbounded convergences have been applied successfully to locally solid topologies on vector lattices. In the present paper, we first expose several properties of various classes of Riesz pseudonorms on vector lattices. We accomplish this by…

Functional Analysis · Mathematics 2019-10-16 Nazife Erkurşun-Özcan , Niyazi Anıl Gezer

We characterize the finite dimensional asymmetric normed spaces which are right bounded and the relation of this property with the natural compactness properties of the unit ball, as compactness and strong compactness. In contrast with some…

General Topology · Mathematics 2017-02-15 Natalia Jonard-Pérez , Enrique A. Sánchez-Pérez

The paper begins by exploring the various definitions of norms on semigroups and then presents a new definition of a normed semigroup. The properties of normed semigroups in the new sense are investigated. The new definition of the norm is…

Rings and Algebras · Mathematics 2015-08-18 V. N. Krishnachandran

We introduce the notion of approximate smoothness in a normed linear space. We characterize this property and show the connections between smoothness and approximate smoothness for some spaces. As an application, we consider in particular…

Functional Analysis · Mathematics 2022-11-08 Jacek Chmieliński , Divya Khurana , Debmalya Sain

The primary goal of this paper is to abstract notions, results and constructions from the theory of categories to the broader setting of plots. Loosely speaking, a plot can be thought of as a non-associative non-unital category with a…

Category Theory · Mathematics 2016-04-06 Salvatore Tringali

We study continuous bounded cohomology of totally disconnected locally compact groups with coefficients in a non-Archimedean valued field $K$. To capture the features of classical amenability that induce the vanishing of real bounded…

Group Theory · Mathematics 2022-04-29 Francesco Fournier-Facio

Many uncertainty sets encountered in control systems analysis and design can be expressed in terms of semialgebraic sets, that is as the intersection of sets described by means of polynomial inequalities. Important examples are for instance…

Optimization and Control · Mathematics 2015-09-15 Fabrizio Dabbene , Didier Henrion , Constantino Lagoa

In a countably normed space which is a linear space equipped with a countable number of pair-wise compatible norms, we prove the existence of a common nearest point (in all norms) from a point outside a nonempty subset if this subset is…

Functional Analysis · Mathematics 2022-12-14 Moustafa M. Zakaria , Nashat Faried , Hany A. El-Sharkawy

A criterion for subnormality of unbounded composition operators in L2-spaces, written in terms of measurable families of probability measures satisfying the so-called consistency condition, is established. It becomes a new characterization…

Functional Analysis · Mathematics 2013-03-27 Piotr Budzynski , Zenon Jan Jablonski , Il Bong Jung , Jan Stochel

In this work we present a principle which says that quasimorphisms can be obtained via "local data" of the group action on certain appropriate spaces. In a rough manner the principle says that instead of starting with a given group and try…

Group Theory · Mathematics 2012-01-31 Gabi Ben Simon

In this work we prove formulas of quasi-additivity for the capacity associated to kernels of radial type in the setting of the boundary of a tree structure and in the setting of compact Ahlfors-regular spaces. We also define a notion of…

Functional Analysis · Mathematics 2023-12-14 Michelangelo Cavina

We give different types of new characterizations for the boundedness and essential norms of generalized weighted composition operators between Zygmund type spaces. Consequently, we obtain new characterizations for the compactness of such…

Functional Analysis · Mathematics 2019-04-01 Mostafa Hassanlou , Amir H. Sanatpour

We study quasi-modular pseudometric spaces as asymmetric refinements of modular metric structures. To each such space we associate canonical forward and backward quasi-uniformities and the corresponding directional topologies. We introduce…

General Topology · Mathematics 2026-02-03 Philani Rodney Majozi

Here we show existence of numerous subsets of Euclidean and metric spaces that, despite having empty interior, still support Poincar\'e inequalities. Most importantly, our methods do not depend on any rectilinear or self-similar structure…

Metric Geometry · Mathematics 2021-11-16 Sylvester Eriksson-Bique , Jasun Gong

The purpose of this paper is to provide tools for analyzing the compactness of sequences in Sobolev spaces, in particular if the sequence gets mapped onto a compact set by some nonlinear operator. Here, our focus lies on a very general…

Analysis of PDEs · Mathematics 2007-11-07 Stefan Krömer , Markus Lilli