Recent content by PhilipsPhysics

Thanks! Pretty much nothing, I know classical mechanics, quantum field theory, electromagnetism can formulated this way by I don't see why (I understand the math, I don't see where it comes from).

Hamiltons Principle and the physcial entity action are the terms in which modern physics is formulated. How do you know that you can always find a Lagrangian for a System which is then used for Hamitlons Principle and the formulation of Action? Why is the action stationary?