##  [Action Functional](/action-functional) 

  ##  [Action Functional](https://natural.quantumdictionary.io/action-functional-0) 

  

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**Natural & Formal Sciences Dictionary**

 







 

 

 

 



 

 

 

 

Definition

A mapping from histories (time-parameterized configurations or fields) to a scalar number obtained by integrating a Lagrangian density along the history; stationary points of the action correspond to admissible dynamics via variational derivatives.