##  [Torsor](/torsor) 

  ##  [Torsor](https://mathlogic.quantumdictionary.io/torsor-0) 

  

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- Natural & Formal Sciences -

**Mathematics & Logic Dictionary**

 







 

 

 

 



 

 

 

 

Definition

A set (or sheaf, scheme, etc.) with a simply transitive action of a group G: there is a free transitive G-action but no distinguished identity point, so the torsor is a 'principal homogeneous space' that becomes isomorphic to G once a basepoint is chosen.