##  [Cobordism](/cobordism) 

  ##  [Cobordism](https://puremath.quantumdictionary.io/cobordism-0) 

  

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**Pure Mathematics Dictionary**

 







 

 

 

 



 

 

 

 

Definition

A relation between closed n-dimensional manifolds: two closed n-manifolds M and N are cobordant if there exists a compact (n+1)-manifold W whose boundary is the disjoint union ∂W ≅ M ⨿ N (orientations accounted for when in the oriented category).