John Carlos Baez on Nostr: - Okay. As for me, I think force and momentum are crucial concepts in Lagrangian ...

- Okay. As for me, I think force and momentum are crucial concepts in Lagrangian mechanics, though *derived from a Lagrangian*. They give a good, simple way to understand the otherwise somewhat mysterious Euler-Lagrange equations. These generalized concepts of force and momentum reduce to Newton's when they should - and not when they shouldn't. So I don't "identify" them with the Newtonian concepts of force and momentum: I treat them as the deeper, better concepts that extend the Newtonian concepts to a vastly more general setting.