Symmetric space: Difference between revisions

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# Given any two [[topologically distinguishable points]] <math>a,b \in X</math>, there exists an open subset <math>U</math> of <math>X</math> such that <math>a \in U, b \notin U</math>.
# Given any two [[topologically distinguishable points]] <math>a,b \in X</math>, there exists an open subset <math>U</math> of <math>X</math> such that <math>a \in U, b \notin U</math>.
# given points <math>a,b \in X</math>, the following are equivalent:
# given points <math>a,b \in X</math>, the following are equivalent:
* There exists an [[open subset]] of <math>X</math> containing <math>a</math> but not <math>b</math>
#* There exists an [[open subset]] of <math>X</math> containing <math>a</math> but not <math>b</math>
* There exists an open subset of <math>X</math> containing <math>b</math> but not <math>a</math>
#* There exists an open subset of <math>X</math> containing <math>b</math> but not <math>a</math>


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

Revision as of 15:40, 28 January 2012

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

Definition

A topological space is termed symmetric if it satisfies the following equivalent conditions:

  1. Its Kolmogorov quotient is a T1 space.
  2. Given any two topologically distinguishable points , there exists an open subset of such that .
  3. given points , the following are equivalent:
    • There exists an open subset of containing but not
    • There exists an open subset of containing but not

Relation with other properties

Stronger properties