nLab
open point

Context

Topology

topology (point-set topology, point-free topology)

see also differential topology, algebraic topology, functional analysis and topological homotopy theory

Introduction

Basic concepts

Universal constructions

Extra stuff, structure, properties

Examples

Basic statements

Theorems

Analysis Theorems

topological homotopy theory

Contents

Definition

Let (X,τ)(X, \tau) be a topological space. Then a point xXx \in X in the underlying set is called an open point if the singleton subset {x}X\{x\} \in X is an open subset, i.e. {x}τ\{x\} \in \tau.

Created on May 9, 2017 at 12:44:55. See the history of this page for a list of all contributions to it.