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A compact set has computable type if any homeomorphic copy of the set which is semicomputable is actually computable. Miller proved that finite-dimensional spheres have computable type, Iljazovi\'c and other authors established the property…

Logic · Mathematics 2023-07-10 Djamel Eddine Amir , Mathieu Hoyrup

Analytic properties of right topological groups have been extensively studied in the compact admissible case (i.e when the group has a dense topological center). This was inspired by the existence of a Haar measure on such groups. In this…

Functional Analysis · Mathematics 2019-11-27 Prachi Loliencar

Downarowicz and Maass (2008) have shown that every Cantor minimal homeomorphism with finite topological rank $K > 1$ is expansive. Bezuglyi, Kwiatkowski, and Medynets (2009) extended the result to non-minimal aperiodic cases. In this paper,…

Dynamical Systems · Mathematics 2016-08-22 Takashi Shimomura

We show that the homeomorphism group of a surface without boundary does not admit a Hausdorff group topology strictly coarser than the compact-open topology. In combination with known automatic continuity results, this implies that the…

Geometric Topology · Mathematics 2022-11-08 J. de la Nuez González

In 2000, Margulis proved that any group of homeomorphisms of the circle either preserves a probabilty measure on the circle or contains a free subgroup in two generators, which is reminiscent of the Tits alternatve for linear groups. In…

Dynamical Systems · Mathematics 2024-06-25 Dominique Malicet , Emmanuel Militon

Let M be the countably infinite metric fan. We show that C_k(M,2) is sequential and contains a closed copy of Arens space S_2. It follows that if X is metrizable but not locally compact, then C_k(X) contains a closed copy of S_2, and hence…

General Topology · Mathematics 2010-06-01 Gary Gruenhage , Boaz Tsaban , Lyubomyr Zdomskyy

We introduce a very natural topology on the set of total orderings of monomials of any algebra having a countable basis over a field. This topological space and some notable subspaces are compact. This topological framework allows us to…

Rings and Algebras · Mathematics 2011-06-02 Roberto Boldini

We study groups of homeomorphic bijections on spaces that are finite unions of compact connected linearly ordered subsets. We prove that all such groups when endowed with the topology of point-wise convergence are topological groups. }

General Topology · Mathematics 2023-12-29 Raushan Buzyakova

In this article we extend to generic $p$-energy minimizing maps between Riemannian manifolds a regularity result which is known to hold in the case $p=2$. We first show that the set of singular points of such a map can be quantitatively…

Analysis of PDEs · Mathematics 2019-10-07 Mattia Vedovato

We show that the group of all pl-homeomorphisms of the reals having bounded slopes surjects on the group $QI({\Bbb R})$ of all quasi-isometries of ${\Bbb R}$. We prove that the following groups can be imbedded in $QI({\Bbb R})$: The group…

Geometric Topology · Mathematics 2007-05-23 Parameswaran Sankaran

Recently geometric hypergraphs that can be defined by intersections of pseudohalfplanes with a finite point set were defined in a purely combinatorial way. This led to extensions of earlier results about points and halfplanes to…

Combinatorics · Mathematics 2024-02-14 Balázs Keszegh

Shape(-and-scale) spaces - configuration spaces for generalized Kendall-type Shape(-and-Scale) Theories - are usually not manifolds but stratified manifolds. While in Kendall's own case - similarity shapes - the shape spaces are…

General Relativity and Quantum Cosmology · Physics 2019-03-13 Edward Anderson

For certain families of compact subsets of the plane, the isomorphism class of the algebra of absolutely continuous functions on a set is completely determined by the homeomorphism class of the set. This is analogous to the…

Functional Analysis · Mathematics 2021-05-31 Shaymaa Al-shakarchi , Ian Doust

In \cite{Kramer11} Kramer proves for a large class of semisimple Lie groups that they admit just one locally compact $\sigma$-compact Hausdorff topology compatible with the group operations. We present two different methods of generalising…

Group Theory · Mathematics 2014-11-06 Rupert McCallum

In analogy to the topological entropy for continuous endomorphisms of totally disconnected locally compact groups, we introduce a notion of topological entropy for continuous endomorphisms of locally linearly compact vector spaces. We study…

Group Theory · Mathematics 2021-01-22 Ilaria Castellano , Anna Giordano Bruno

In the first part of this work we have established an efficient method to obtain a topological classification of locally discrete, finitely generated, virtually free subgroups of real-analytic circle diffeomorphisms. In this second part we…

We study topologization of the semigroup $\mathscr{O\!\!I}\!_n(L)$ of finite partial order isomorphisms of a bounded rank of an infinite linear ordered set $(L,\leqslant)$. In particular we show that every $T_1$ left-topological…

Group Theory · Mathematics 2025-12-01 Oleg Gutik , Maksym Shchypel

We show that a topological Cantor set in the line has at most countably many real-analytic, onto self-maps.

Dynamical Systems · Mathematics 2023-12-27 Michael Hochman

We consider the problem of topological linearization of smooth (C infinity or real analytic) control systems, i.e. of their local equivalence to a linear controllable system via point-wise transformations on the state and the control…

Optimization and Control · Mathematics 2011-12-14 Laurent Baratchart , Jean-Baptiste Pomet

This is a glossary of notions and methods related with the topological theory of collections of affine planes, including braid groups, configuration spaces, order complexes, stratified Morse theory, simplicial resolutions, complexes of…

Geometric Topology · Mathematics 2014-07-29 Victor A. Vassiliev