Me 20090909:

Based on K. Young’s notes:

Action S should be defined in a way that

1. It is invariant.

2. It is additive.

3. It fulfills the experimental results.

Me 20090909:

Hamiltonian (in classical mechanics) may not be the total energy of the system.

The formal definition should be H = pv – L.

Me 20090909:

Principle of least time is the principle of least action for photon via de Broglie’s relation.

2009.11.30 Monday (c) ACHK