The variational principle
The variational principle
This chapter looks at the equations of motion of a particle and describes the conditions that they present. It is not always a minimum, more commonly a saddle point. This chapter follows the ancient method of Euler and Lagrange to derive this fact. The quantum mechanical origin of this principle is also outlined: the average over all paths is dominated by the extremum in the limit of small Planck's constant.
Keywords: Planck's constant, Lagrange, saddle point
Oxford Scholarship Online requires a subscription or purchase to access the full text of books within the service. Public users can however freely search the site and view the abstracts and keywords for each book and chapter.
Please, subscribe or login to access full text content.
If you think you should have access to this title, please contact your librarian.
To troubleshoot, please check our FAQs , and if you can't find the answer there, please contact us .