 ##  [Index Jump](/index-jump) 

  ##  [Index Jump](https://mathlogic.quantumdictionary.io/index-jump-0) 

  
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- Natural &amp; Formal Sciences -

**Mathematics &amp; Logic Dictionary**

 
Definition

A discontinuous change by an integer in the Fredholm index of a parameterized family of linear operators that occurs when the parameter crosses values at which ellipticity, boundary conditions, or the Fredholm property fail.