Simply connected domain: Difference between revisions

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(New page: ==Definition== A domain (open connected subset) in <math>\mathbb{C}</math> is termed a '''simply connected domain''' if it satisfies the following equivalent conditions: * It is simp...)
 
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* Its first homology group is trivial
* Its first homology group is trivial
* Any cycle in it is zero-homologous: it does not wind around any point in the complement of the domain
* Any cycle in it is zero-homologous: it does not wind around any point in the complement of the domain
* Every holomorphic function is integrable, i.e. has a global primitive
* The complement of the domain in the [[Riemann sphere]] is a connected set
* The complement of the domain in the [[Riemann sphere]] is a connected set

Revision as of 20:02, 20 April 2008

Definition

A domain (open connected subset) in is termed a simply connected domain if it satisfies the following equivalent conditions:

  • It is simply connected as a topological space i.e. its fundamental group is trivial
  • Its first homology group is trivial
  • Any cycle in it is zero-homologous: it does not wind around any point in the complement of the domain
  • Every holomorphic function is integrable, i.e. has a global primitive
  • The complement of the domain in the Riemann sphere is a connected set