English
Related papers

Related papers: Movable categories

200 papers

We show that topological amenability of an action of a countable discrete group on a compact space is equivalent to the existence of an invariant mean for the action. We prove also that this is equivalent to vanishing of bounded cohomology…

Group Theory · Mathematics 2010-04-05 Jacek Brodzki , Graham A. Niblo , Piotr Nowak , Nick Wright

Topological complexity for spaces was introduced by M. Farber as a minimal number of continuity domains for motion planning algorithms. It turns out that this notion can be extended to the case of not necessarily commutative C*-algebras.…

Operator Algebras · Mathematics 2017-04-03 Vladimir Manuilov

The first author introduced a measure of compactness for families of sets, relative to a class of filters, in the context of convergence approach spaces. We characterize a variety of maps (types of quotient maps, closed maps, and variants…

General Topology · Mathematics 2015-07-28 Frédéric Mynard , William Trott

In this paper we study analogues of amenability for topological groups in the context of definable structures. We prove fixed point theorems for such groups. More importantly, we propose definitions for definable actions and continuous…

Logic · Mathematics 2018-12-14 Alf Onshuus , Luis Carlos Suárez

The concept of relative sectional category expands upon classical sectional category theory by incorporating the pullback of a fibration along a map. Our paper aims not only to explore this extension but also to thoroughly investigate its…

Algebraic Topology · Mathematics 2024-05-31 Jose Manuel Garcia Calcines

Certain notions of convergence of sequences functions such as pointwise convergence and (uniform) convergence on compact or bounded sets come from suitable topological function spaces; see [1]. Under certain conditions these topologies…

General Mathematics · Mathematics 2025-12-22 Luis David Rivera

Many mechanical systems have configuration spaces that admit symmetries. Mathematically, such symmetries are modelled by the action of a group on a topological space. Several variations of topological complexity have emerged that take…

Algebraic Topology · Mathematics 2024-02-05 Mark Grant

We define a tracelike transformation to be a natural family of conjugation invariant maps $T_{x,C}: hom_C(x,x) \to hom_C(1,1)$ for all dualisable objects $x$ in any symmetric monoidal infinity-category $C$. This generalises the trace from…

Category Theory · Mathematics 2022-03-24 Jan Steinebrunner

We recast the tools of ``global causal analysis'' in accord with an approach to the subject animated by two distinctive features: a thoroughgoing reliance on order-theoretic concepts, and a utilization of the Vietoris topology for the space…

General Relativity and Quantum Cosmology · Physics 2009-10-28 R. D. Sorkin , E. Woolgar

We introduce moment maps for continuous unitary representations of general topological groups. For solvable separable locally compact groups, we prove that the closure of the image of the moment map of any representation is convex.

Representation Theory · Mathematics 2014-08-21 Daniel Beltita , Mihai Nicolae

In this article we introduce the local versions of the Voevodsky category of motives with Z/p-coefficients over a field k, parameterized by finitely-generated extensions of k. We introduce the, so-called, flexible fields, passage to which…

Algebraic Geometry · Mathematics 2020-12-23 Alexander Vishik

Pursuing the notions of ambidexterity and higher semiadditivity as developed by Hopkins and Lurie, we prove that the span $\infty$-category of $m$-finite spaces is the free $m$-semiadditive $\infty$-category generated by a single object.…

Algebraic Topology · Mathematics 2020-07-15 Yonatan Harpaz

We firstly introduce some key concepts in category theory, such as quotient category, completion of limits, $\mathrm{Mor}$ category, and so on; then give the concept of topology algebras and sheaves, and discuss how to restore the structue…

Category Theory · Mathematics 2019-06-11 Dezhao Zhang

Let $X$ be a compact toric variety. Let $Hol$ denote the space of based holomorphic maps from $CP^1$ to $X$ which lie in a fixed homotopy class. Let $Map$ denote the corresponding space of continuous maps. We show that $Hol$ has the same…

alg-geom · Mathematics 2008-02-03 Martin A. Guest

The concept of process is ubiquitous in science, engineering and everyday life. Category theory, and monoidal categories in particular, provide an abstract framework for modelling processes of many kinds. In this paper, we concentrate on…

Category Theory · Mathematics 2019-06-19 Valtteri Lahtinen , Antti Stenvall

We classify compact homogeneous geometries of irreducible spherical type and rank at least 2 which admit a transitive action of a compact connected group, up to equivariant 2-coverings. We apply our classification to polar actions on…

Group Theory · Mathematics 2014-04-17 Linus Kramer , Alexander Lytchak

Implicative algebras have been recently introduced by Miquel in order to provide a unifying notion of model, encompassing the most relevant and used ones, such as realizability (both classical and intuitionistic), and forcing. In this work,…

Category Theory · Mathematics 2023-12-06 Samuele Maschio , Davide Trotta

We show that metric abstract elementary classes (mAECs) are, in the sense of [LR] (i.e. arXiv:1404.2528), coherent accessible categories with directed colimits, with concrete $\aleph_1$-directed colimits and concrete monomorphisms. More…

Logic · Mathematics 2017-03-30 Michael Lieberman , Jiri Rosicky

We formulate a connection between a topological and a geometric category. The former is the idempotent completion of the (horizontal) trace of the affine Hecke category, while the latter is the equivariant derived category of the…

Geometric Topology · Mathematics 2024-12-10 Eugene Gorsky , Andrei Neguţ

Cyclic poset are generalizations of cyclically ordered sets. In this paper we show that any cyclic poset gives rise to a Frobenius category over any discrete valuation ring R. The continuous cluster categories of arXiv:1209.1879 are…

Representation Theory · Mathematics 2013-10-03 Kiyoshi Igusa , Gordana Todorov