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Related papers: A note on topological amenability

200 papers

This is a short survey of amenable equivalence relations.

Logic · Mathematics 2018-09-05 Justin Tatch Moore

By giving an interesting characterisation of amenable multiplicative unitaries in term of one dimensional representations, we show in a simple way that bicrossproducts of amenable locally compact groups is both amenable and coamenable.

Operator Algebras · Mathematics 2007-05-23 Chi-Keung Ng

For a topological group $G$, amenability can be characterized by the amenability of the convolution Banach algebra $L^1(G)$. Here a Banach algebra $A$ is called amenable if every bounded derivation from $A$ into any dual--type…

Functional Analysis · Mathematics 2025-07-01 Hikaru Awazu

We investigate the possibility of replacing the topology of convergence in probability with convergence in $L^1$. A characterization of continuous linear functionals on the space of measurable functions is also obtained.

Functional Analysis · Mathematics 2013-07-18 Gianluca Cassese

A way to characterize the space of leaves of a foliation in terms of connections is proposed. A particular example of vertex algebra cohomology of codimension one foliations on complex curves is considered.

Functional Analysis · Mathematics 2022-04-06 A. Zuevsky

In this paper, we countinue our work in \cite{11}. We show that $L^{1}(G,w)$ is $\phi_{0}$-biprojective if and only if $G$ is compact, where $\phi_{0}$ is the augmentation character. We introduce the notions of character Johnson amenability…

Functional Analysis · Mathematics 2018-09-11 A. Sahami

We show that for every countable group, any sequence of approximate homomorphisms with values in permutations can be realized as the restriction of a sofic approximation of an orbit equivalence relation. Moreover, this orbit equivalence…

Group Theory · Mathematics 2024-11-20 Ben Hayes , Srivatsav Kunnawalkam Elayavalli

This manuscript develops a geometric approach to ordinary cohomology of smooth manifolds, constructing a cochain complex model based on co-oriented smooth maps from manifolds with corners. Special attention is given to the pull-back product…

Algebraic Topology · Mathematics 2026-05-01 Greg Friedman , Anibal M. Medina-Mardones , Dev Sinha

Beyond the locally compact case, equivalent notions of amenability diverge, and some properties no longer hold, for instance amenability is not inherited by topological subgroups. This investigation is guided by some amenability-type…

Group Theory · Mathematics 2025-03-05 Vladimir G. Pestov , Friedrich Martin Schneider

In this paper, we study the notion of $\phi$-biflatness, $\phi$-biprojectivity, approximate biprojectivity and Johnson pseudo-contractibility for a new class of Banach algebras. Using this class of Banach algebras we give some examples…

Functional Analysis · Mathematics 2018-06-06 Amir Sahami

We introduce a consistent estimator for the homology (an algebraic structure representing connected components and cycles) of level sets of both density and regression functions. Our method is based on kernel estimation. We apply this…

Statistics Theory · Mathematics 2016-09-30 Omer Bobrowski , Sayan Mukherjee , Jonathan E. Taylor

In this paper we introduce a novel family of attributed graphs for the purpose of shape discrimination. Our graphs typically arise from variations on the Mapper graph construction, which is an approximation of the Reeb graph for point cloud…

Algebraic Topology · Mathematics 2023-07-03 Justin Curry , Washington Mio , Tom Needham , Osman Berat Okutan , Florian Russold

In this article, we study and review some aspects of twisted cohomologies on algebraic and analytic varieties. We compared such cohomologies in both the algebraic and analytic categories and defined two types of twisting parameters in the…

Algebraic Geometry · Mathematics 2026-05-06 M. S. Islam , A. R. Mishkaat

One of the prime motivation for topology was Homotopy theory, which captures the general idea of a continuous transformation between two entities, which may be spaces or maps. In later decades, an algebraic formulation of topology was…

Category Theory · Mathematics 2025-11-24 Suddhasattwa Das

In this paper, we deal with cohomological properties of weak amenability, cyclic amenability, cyclic weak amenability and point amenability of Banach algebras. We look at some hereditary properties of them and show that continuous…

Functional Analysis · Mathematics 2022-10-10 M. J. Mehdipour , A. Rejali

A basic assumption of tiling theory is that adjacent tiles can meet in only a finite number of ways, up to rigid motions. However, there are many interesting tiling spaces that do not have this property. They have "fault lines", along which…

Dynamical Systems · Mathematics 2007-05-23 Natalie Priebe Frank , Lorenzo Sadun

Topological data analysis provides a collection of tools to encapsulate and summarize the shape of data. Currently it is mainly restricted to \emph{mapper algorithm} and \emph{persistent homology}. In this paper we introduce new…

Algebraic Topology · Mathematics 2019-01-23 Paweł Dłotko

We present the set of axioms for topological space with the operation of boundary as primitive notion.

General Topology · Mathematics 2007-05-23 K. Leśniak

The notion of homomorphism indistinguishability offers a combinatorial framework for characterizing equivalence relations of graphs, in particular equivalences in counting logics within finite model theory. That is, for certain graph…

Logic in Computer Science · Computer Science 2025-06-26 Georg Schindling

In the 1950s Morse defined the analogue of Morse functions for topological manifolds. In many instances, when mathematicians are using techniques on topological manifolds that appear to be Morse-theoretic in nature, there is a topological…

Geometric Topology · Mathematics 2026-03-11 Ingrid Irmer