##  [Nonstandard Analysis](/nonstandard-analysis) 

  ##  [Nonstandard Analysis](https://puremath.quantumdictionary.io/nonstandard-analysis-0) 

  

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- Mathematics & Logic -

**Pure Mathematics Dictionary**

 







 

 

 

 



 

 

 

 

Definition

A rigorous framework that extends the real numbers to a larger ordered field (or model) containing infinitesimal and infinite elements—the hyperreals—and uses model-theoretic tools (transfer principle, internal/external distinction, saturation) to justify infinitesimal reasoning and rework calculus and measure constructions.