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2025-05-03 23:03:24 UTC
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Ray Lee on Nostr: Given the Hamiltonian in QM pushes the state through time, and the Lagrangian is also ...

Given the Hamiltonian in QM pushes the state through time, and the Lagrangian is also an energy (therefore, in QM at least, should also evolve something through time, I think?), can we consider the Lagrangian being the evolution of the state function in some lower-energy view? Like maybe the particle's rest frame, rather than something fixed and more global?

I never was able to get a feel for the action in classical mechanics, other than it was formally true and made solving a lot of wacky problems way easier. So thanks for the pointer to the Hamilton-Jacobi equation. I like that Schrödinger's equation can sorta be viewed as the diffusion equation with a phase tossed in, so it's interesting and surprising that there's an analogue in classical mechanics. (Maybe I was absent from class that day.)