Singular chain complex: Difference between revisions

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The '''singular complex''' associated with a topological space is defined as the following chain complex of Abelian groups:
The '''singular complex''' associated with a topological space is defined as the following chain complex of Abelian groups:


* The <math>n^{th}</math> member of this complex is the <math>n^{th}</math> chain group, or the group of [[singular chain|singular <math>n</math>-chains]]. This is essentially the free Abelian group on the set of all [[singular simplex|singular <math>n</math>-simplices]].
* The <math>n^{th}</math> member of this complex is the <math>n^{th}</math> chain group, or the group of [[singular chain|singular n-chains]]. This is essentially the free Abelian group on the set of all [[singular simplex|singular <math>n</math>-simplices]].


* The '''boundary map''' goes from the <math>n^{th}</math> chain group to the <math>(n-1)^{th}</math> chain group, and it essentially sends each singular simplex to a signed sum of its codimension one faces.
* The '''boundary map''' goes from the <math>n^{th}</math> chain group to the <math>(n-1)^{th}</math> chain group, and it essentially sends each singular simplex to a signed sum of its codimension one faces.

Revision as of 23:25, 30 September 2007

Template:Chain complex

Definition

The singular complex associated with a topological space is defined as the following chain complex of Abelian groups:

  • The boundary map goes from the nth chain group to the (n1)th chain group, and it essentially sends each singular simplex to a signed sum of its codimension one faces.