Talk:Variational principle

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I don't see how this is any different from the Euler-Lagrange formalism or action principle. The bottom half of the article is even about some approximation method, which seems completely out of place. --MarSch 13:34, 22 Jun 2005 (UTC)

Hi MarSch. For me, the variational principle is indeed simply the principle of least action, but written out for a hamiltonian and electronic system as described in quantum chemistry (as in the section I added). I don't know of any other meaning, especially in pure physics. I think the article needs to be reorganized, the introduction restated. I was planning to do that some time ago, but lacked the time. Karol 20:30, Jun 22, 2005 (UTC)

The approximation method I was referring to is the variational method. Does it have anything to do with the principle of stationary action? It is claimed in that article, but not explained. --MarSch 10:02, 23 Jun 2005 (UTC)

The source of the confusion here seems to be the various different uses of the term 'variational principle'. This article has a list of rather unrelated things that could possibly be called variational principles, and then a decent description of one particular example. The variational principle (or variational theorem) in quantum mechanics is not an approximation method, is not out of place, and is exactly the basis of the variational method in quantum mechanics.

[edit] Merge with Calculus of Variations?

Should this article be merged with the calculus of variations page? It seems like this page only details some basic applications to the calculus of variations and explains some general aims of the calculus of variations. The C of V page could use a better explanation on its overall aims. --69.180.18.247 14:42, 4 September 2006 (UTC)