- #1
- 4,807
- 32
Based on the proof given in the action article of wiki (http://en.wikipedia.org/wiki/Action_(physics)#Euler-Lagrange_equations_for_the_action_integral), it would seems that the statement of the "central thm of calculus of variation"(http://en.wikipedia.org/wiki/Euler-Lagrange_equations#Statement) is in fact an [itex]\Leftrightarrow[/itex] one. I.e. not just "IF action is extremized, THEN L satisfies E-L", but rather "Action is extremized, iff L satisfies E-L"
someone can confirm?
someone can confirm?