The variables of the Lagrangian, e.g. the angles of a double pendulum. From that example it is clear that these variables don't need to be simple things like cartesian coordinates or polar coordinates (although these tend to be the overwhelming majority of simple case encountered): any way to describe the system is perfectly valid.
In quantum field theory, those variables are actually fields.
- Lagrangian | 17, 434, 3
- Lagrangian mechanics | 907, 2k, 19
- Mechanics | 14, 2k, 46
- Physics | 276, 40k, 705
- Natural science | 0, 49k, 1k
- Science | 0, 53k, 1k
- Ciro Santilli's Homepage | 262, 182k, 3k
- Manifold | 164, 424, 6
- Noether's theorem | 247, 259, 1
- Quantum electrodynamics Lagrangian | 40, 309, 1
- Schrodinger equation | 555, 4k, 55