English
Related papers

Related papers: NTP2 topological structures

200 papers

Using countable support iteration of $S$-proper posets, for some appropriate stationary set $S$, we obtain a generic extension of the constructible universe, in which $\mathfrak{b}=\mathfrak{c}=\aleph_2$ and there is a maximal cofinitary…

Logic · Mathematics 2016-03-10 Vera Fischer , Sy David Friedman , Asger Törnquist

Topologies can be expanded with the help of ideals, using the local function, an operator resembling the closure of a set. The aim of this paper is to define the ideals which enable us to create this topology $\tau^{*}$ on $X$…

General Topology · Mathematics 2023-12-07 Anika Njamcul , Aleksandar Pavlović

Let ${\mathcal S}(\R)$ be an o-minimal structure over $\R$, $T \subset \R^{k_1+k_2+\ell}$ a closed definable set, and $$ \displaylines{\pi_1: \R^{k_1+k_2+\ell}\to \R^{k_1 + k_2}, \pi_2: \R^{k_1+k_2+\ell}\to \R^{\ell}, \ \pi_3: \R^{k_1 +…

Combinatorics · Mathematics 2011-02-21 Saugata Basu

Fix a d-minimal expansion of an ordered field. We consider the space $\mathcal D^p(M)$ of definable $\mathcal C^p$ functions defined on a definable $\mathcal C^p$ submanifold $M$ equipped with definable $\mathcal C^p$ topology. The set of…

Logic · Mathematics 2025-02-04 Masato Fujita

We settle some open problems in the special case of groups in o-minimal structures, such as the equality of G^00 and G^000 and the equivalence of definable amenability and existence of a type with bounded orbit. We prove almost exactness of…

Logic · Mathematics 2011-01-11 Anand Pillay

This paper forms the second part of a series by the authors [GMV1,GMV3] concerning the structure theory of nilspaces of Antol\'in Camarena and Szegedy. A nilspace is a compact space $X$ together with closed collections of cubes…

Dynamical Systems · Mathematics 2018-01-03 Yonatan Gutman , Freddie Manners , Péter P. Varjú

Let $C(\mathbf I)$ be the set of all continuous self-maps from ${\mathbf I}=[0,1]$ with the topology of uniformly convergence. A map $f\in C({\mathbf I})$ is called a transitive map if for every pair of non-empty open sets $U,V$ in…

Dynamical Systems · Mathematics 2020-06-18 Zhaorong He , Jian Li , Zhongqiang Yang

We prove structure theorems for o-minimal definable subsets $S\subset G$ of definable groups containing large multiplicative structures, and show definable groups do not have bounded torsion arbitrarily close to the identity. As an…

Logic · Mathematics 2022-06-17 Hunter Spink

We prove that Tietze Extension does not always exist in constructive mathematics if closed sets on which the function we are extending are defined as sequentially closed sets. Firstly, we take a discrete metric space as our topological…

General Topology · Mathematics 2025-08-19 Shun Ding , Yang Wan , Luofei Wang , Siqi Xiao

A $G$-invariant version of definable Tietze extension theorem for definably complete structures is proved when a definably compact definable topological group $G$ acts definably and continuously on the definable set.

Logic · Mathematics 2026-01-09 Masato Fujita , Tomohiro Kawakami

In this paper, first we obtain some new and interesting results on projective modules and on the upper topology of an ordinal number. Then it is shown that the rank map of a locally of finite type projective module is continuous with…

Commutative Algebra · Mathematics 2019-11-01 Abolfazl Tarizadeh

In this paper, we introduce the notion of expanding topological space. We define the topological expansion of a topological space via local multi-homeomorphism over coproduct topology, and we prove that the coproduct family associated to…

General Mathematics · Mathematics 2021-07-13 Helene Porchon

We show that the cyclically ordered-abelian groups expanding $(\mathbb{Z};+)$ contain a continuum-size family of dp-minimal structures such that no two members define the same subsets of $\mathbb{Z}$.

Logic · Mathematics 2017-11-15 Minh Chieu Tran , Erik Walsberg

We give a general exposition of model theoretic connected components of groups. We show that if a group G has NIP, then there exists the smallest invariant (over some small set) subgroup of G with bounded index (Theorem 5.3). This result…

Logic · Mathematics 2010-02-09 Jakub Gismatullin

We consider an arbitrary topological group $G$ definable in a structure $\mathcal M$, such that some basis for the topology of $G$ consists of sets definable in $\mathcal M$. To each such group $G$ we associate a compact $G$-space of…

Logic · Mathematics 2015-06-15 Ya'Acov Peterzil , Sergei Starchenko

We are going to prove that if the theory of a structure $\mathcal M=\langle \mathbb{N}, \Sigma \rangle$ is decidable and the standard order $<$ on natural numbers $\mathbb{N}$ is definable in $\mathcal M$, then there is a nontrivial…

Logic · Mathematics 2022-11-30 Sergei Soprunov

We give necessary and sufficient conditions on a non-oscillatory curve in an o-minimal field such that, for any bounded definable function, the germ of the function on an initial segment of the curve can be continuously extended to a closed…

Logic · Mathematics 2011-04-22 Janak Ramakrishnan

I shall describe a general model-theoretic task to construct expansions of pseudofinite structures and discuss several examples of particular relevance to computational complexity. Then I will present one specific situation where finding a…

Logic · Mathematics 2017-02-10 Jan Krajicek

The dynamics of symbolic systems, such as multidimensional subshifts of finite type or cellular automata, are known to be closely related to computability theory. In particular, the appropriate tools to describe and classify topological…

Dynamical Systems · Mathematics 2019-06-06 Silvere Gangloff , Alonso Herrera , Cristobal Rojas , Mathieu Sablik

In this paper we work in an arbitrary o-minimal structure with definable Skolem functions and we prove that definably connected, locally definable manifolds are uniformly definably path connected, have an admissible cover by definably…

Logic · Mathematics 2019-11-12 Bruno Dinis , Mário J. Edmundo , Marcello Mamino
‹ Prev 1 4 5 6 7 8 10 Next ›