13 - Symmetries & Conservation Laws
This lecture focuses on the relation between continuous symmetries of the Lagrangian and conserved quantities. Generalized coordinates and canonical conjugate momentum are introduced.
Topics:
Symmetry and conservation laws: they are always related
Review of the principle of least action (stationary action)
Generalized coordinates and their canonical conjugate momentum
Conserved quantities and translation and rotation symmetry
Noether theorem concept and outline
Momentum conservation as a consequence of translation symmetry
Angular momentum conservation as a consequence of rotational symmetry
The harmonic oscillator
Discrete symmetries have no associated conserved quantities in classical mechanics
References:
Symmetry and conservation laws
Noether’s theorem
Harmonic oscillator
Generalized coordinates
Angular momentum conservation