Locally regular space: Difference between revisions

From Topospaces
(Created page with "==Definition== A topological space <math>X</math> is termed '''locally regular''' if it satisfies the following equivalent conditions: # It has a basis of [[open sub...")
 
No edit summary
 
(One intermediate revision by the same user not shown)
Line 4: Line 4:


# It has a [[basis]] of [[open subset]]s each of which is a [[regular space]] under the [[subspace topology]].
# It has a [[basis]] of [[open subset]]s each of which is a [[regular space]] under the [[subspace topology]].
# For any <math>x \in X</math>, there exists an [[open subset]] <math>U</math> containing <math>x</math> such that <math>U</math> is a [[regular space]] with the [[subspace topology]].
# For any <math>x \in X</math> and open subset <math>V</math> containing <math>x</math>, there exists an open subset <math>U</math> containing <math>x</math> such that <math>U \subseteq V</math> and <math>U</math> is a [[regular space]] with the [[subspace topology]].
# For any <math>x \in X</math> and open subset <math>V</math> containing <math>x</math>, there exists an open subset <math>U</math> containing <math>x</math> such that <math>U \subseteq V</math> and <math>U</math> is a [[regular space]] with the [[subspace topology]].
{{topospace property}}


==Relation with other properties==
==Relation with other properties==

Latest revision as of 17:24, 28 January 2012

Definition

A topological space X is termed locally regular if it satisfies the following equivalent conditions:

  1. It has a basis of open subsets each of which is a regular space under the subspace topology.
  2. For any xX, there exists an open subset U containing x such that U is a regular space with the subspace topology.
  3. For any xX and open subset V containing x, there exists an open subset U containing x such that UV and U is a regular space with the subspace topology.

This article defines a property of topological spaces: a property that can be evaluated to true/false for any topological space|View a complete list of properties of topological spaces

Relation with other properties

Stronger properties

Property Meaning Proof of implication Proof of strictness (reverse implication failure) Intermediate notions
regular space