##  [Obstruction to Descent](/obstruction-descent) 

  ##  [Obstruction to Descent](https://puremath.quantumdictionary.io/obstruction-descent-0) 

  

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- Mathematics & Logic -

**Pure Mathematics Dictionary**

 







 

 

 

 



 

 

 

 

Definition

A cohomological or categorical class, condition, or phenomenon that prevents an object defined on a cover, extension, or auxiliary base from being realized as the pullback or restriction of an object on a specified smaller base; it obstructs descent along the given cover or morphism.