What is the variational principle and how does it apply to physics?

Thread starter War-Saw
Start date Jun 7, 2006
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Principle Variational principle

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The variational principle is a fundamental concept in physics that states that the path taken by a system is the one that minimizes or extremizes a certain quantity, often action. It applies to various areas, including wave propagation, where it relates to the least time principle and Huygens' wave fronts, as well as classical mechanics through Hamilton's principle of least action. The principle is crucial for deriving equations of motion and understanding physical systems. For further information, refer to reliable physics textbooks or academic sources that cover variational principles in detail. Understanding these principles is essential for grasping advanced topics in both classical and quantum physics.

Jun 7, 2006

War-Saw

I need someone who can briefly (in easy way) explain me the variational principle or tell me where (in checked source) I can find this. I will be very greatful.

Last edited: Jun 7, 2006

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Jun 8, 2006

lightgrav

Homework Helper

There are several variational principles ...
a) wave propagation (least time, a special case of Huygens wave fronts;
... generalized to Feynman path)
b) classsical mechanics , usually Hamilton's extreme action integral.

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