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Related papers: Amenable category and complexity

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In this paper we introduce the notion of scale pressure and measure theoretic scale pressure for amenable group actions. A variational principle for amenable group actions is presented. We also describe these quantities by pseudo-orbits.…

Dynamical Systems · Mathematics 2020-12-03 Dandan Cheng , Qian Hao , Zhiming Li

We study a uniform, quantitative form of the amenability-hyperfiniteness paradigm for bounded-degree Borel graphs generating countable Borel equivalence relations. We introduce \emph{uniform Borel amenability} and prove that it is…

Dynamical Systems · Mathematics 2026-05-19 Gábor Elek , Ádám Timár

We introduce the notion of inductive category in a model category and prove that it agrees with the Ganea approach given by Doeraene. This notion also coincides with the topological one when we consider the category of (well-) pointed…

Algebraic Topology · Mathematics 2009-02-28 J. M. Garcia-Calcines , P. R. Garcia-Diaz

This paper defines analysis-suitable T-splines for arbitrary degree (including even and mixed degrees) and arbitrary dimension. We generalize the concept of anchor elements known from the two-dimensional setting, extend existing concepts of…

Numerical Analysis · Mathematics 2023-04-28 Robin Görmer , Philipp Morgenstern

We introduce an Ulam-type stability condition for positive definite maps defined on a countable group and prove that this condition characterizes amenability.

Group Theory · Mathematics 2022-10-21 Mikaël Pichot , Erik Séguin

The sectional category of a subgroup inclusion $H \hookrightarrow G$ can be defined as the sectional category of the corresponding map between Eilenberg--MacLane spaces. We extend a characterization of topological complexity of aspherical…

Algebraic Topology · Mathematics 2023-12-13 Zbigniew Błaszczyk , José Carrasquel , Arturo Espinosa Baro

Hyperfiniteness or amenability of measurable equivalence relations and group actions has been studied for almost fifty years. Recently, unexpected applications of hyperfiniteness were found in computer science in the context of testability…

Functional Analysis · Mathematics 2012-05-31 Gabor Elek

A groupoid is a small category in which each morphism has an inverse. A topological groupoid is a groupoid in which both sets of objects and morphisms have topologies such that all groupoid structure maps are continuous. The notion of…

Differential Geometry · Mathematics 2007-05-23 Osman Mucuk , Ilhan Icen

We give simple upper bounds for rational sectional category and use them to compute invariants of the type of Farber's topological complexity of rational spaces. In particular we show that the sectional category of formal morphisms reaches…

Algebraic Topology · Mathematics 2015-03-10 J. G. Carrasquel-Vera

We propose a new homotopy invariant for Lie groupoids which generalizes the classical Lusternik-Schnirelmann category for topological spaces. We use a bicategorical approach to develop a notion of contraction in this context. We propose a…

Algebraic Topology · Mathematics 2009-08-25 Hellen Colman

In this paper, we provide several characterisations for uniform amenability concerning a family of finitely generated groups. More precisely, we show that the Hulanicki-Reiter condition for uniform amenability can be weakened in several…

Metric Geometry · Mathematics 2022-12-13 Jingming Zhu , Jiawen Zhang

In this paper configuration spaces of smooth manifolds are considered. The accent is made on actions of certain groups (mostly $p$-tori) on this spaces by permuting their points. For such spaces the cohomological index, the genus in the…

Algebraic Topology · Mathematics 2011-07-06 R. N. Karasev

We study thick subcategories defined by modules of complexity one in $\underline{\md}R$, where $R$ is the exterior algebra in $n+1$ indeterminates.

Representation Theory · Mathematics 2019-04-04 Otto Kerner , Dan Zacharia

Let $X$ be a two-cell complex with attaching map $\alpha\colon S^q\to S^p$, and let $C_X$ be the cofiber of the diagonal inclusion $X\to X\times X$. It is shown that the topological complexity (${\rm TC}$) of $X$ agrees with the…

Algebraic Topology · Mathematics 2016-08-01 Jesús González , Mark Grant , Lucile Vandembroucq

We give a combinatorial characterization of amenability of monomial algebras and prove the existence of monomial Folner sequences, answering a question due to Ceccherini-Silberstein and Samet-Vaillant. We then use our characterization to…

Rings and Algebras · Mathematics 2022-11-15 Jason P. Bell , Be'eri Greenfeld

Following an idea of Bendersky-Gitler, we construct an isomorphism between Anderson's and Arone's complexes modelling the chain complex of a map space. This allows us to apply Shipley's convergence theorem to Arone's model. As a corollary,…

Algebraic Topology · Mathematics 2011-02-09 Semen Podkorytov

We prove that the homotopy theory of parsummable categories (as defined by Schwede) with respect to the underlying equivalences of categories is equivalent to the usual homotopy theory of symmetric monoidal categories. In particular, this…

Category Theory · Mathematics 2021-05-13 Tobias Lenz

Applied category theory often studies symmetric monoidal categories (SMCs) whose morphisms represent open systems. These structures naturally accommodate complex wiring patterns, leveraging (co)monoidal structures for splitting and merging…

Category Theory · Mathematics 2025-09-03 Marius Furter , Yujun Huang , Gioele Zardini

Averaging linear functional on the space continuous functions of the group of diffeomorphisms of interval is found. Amenability of several discrete subgroups of the group of diffeomorphisms $\Diff^3([0,1])$ of interval is prove. In…

Group Theory · Mathematics 2011-01-17 E. T. Shavgulidze

Let $\mathcal{A}$ be a set of positive numbers. A graph $G$ is called an $\mathcal{A}$-embeddable graph in $\mathbb{R}^d$ if the vertices of $G$ can be positioned in $\mathbb{R}^d$ so that the distance between endpoints of any edge is an…

Computational Complexity · Computer Science 2017-10-17 Mikhail Tikhomirov