##  [Fredholm Index](/fredholm-index) 

  ##  [Fredholm Index](https://puremath.quantumdictionary.io/fredholm-index-0) 

  

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- Mathematics & Logic -

**Pure Mathematics Dictionary**

 







 

 

 

 



 

 

 

 

Definition

An integer-valued invariant of a Fredholm operator equal to the dimension of its kernel minus the dimension of its cokernel; it measures the finite-dimensional obstruction to invertibility and links analytic operator theory to topological information.