##  [Viscosity Solution](/viscosity-solution) 

  ##  [Viscosity Solution](https://natural.quantumdictionary.io/viscosity-solution-0) 

  

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**Natural & Formal Sciences Dictionary**

 







 

 

 

 



 

 

 

 

Definition

A viscosity solution is a generalized notion of solution for certain nonlinear first- and second-order partial differential equations defined by comparison with smooth test functions rather than by pointwise classical derivatives.