The most fundamental principle in physics is called 'The Principle of Least Action'. It also happens to be a good principle to live by during these trying times
-
Writing the Lagrangian for your system gets you the action. It's already something you do before you attempt to minimize it. The point is that you don't have to minimize it, you can just sum over all histories, and the interfernece reproduce the classical least action principle.
ahh i'm remembering this now .. that's fascinating and would indeed be more fundamental in my book .. 'interference' though i'm not sure i would call quantum interference .. iirc isn't it just that when h->0 you can use steepest descent cause of the ever more rapid oscillations?
-
-
or is it true quantum interference? i've sadly only done path integrals in QFT and not QM, so i don't have much of an intuition for it
-
As far as I know, it's true interference. I may be wrong about this, but we even have some experiments that seem to suggest these crazy Feynman paths are real. https://physicsworld.com/a/photons-weave-their-way-through-a-triple-slit/ … So I'd say this approach is more fundamental and makes the least amount of assumptions.
- 1 more reply
New conversation -
-
-
You don't need h->0 at all to use it. You can even derive the uncertainty principle from the final probability distribution for multiple final outcomes for a finite h. When h->0, you simply get, exactly, the path of least-action as a Dirac delta distribution over outcomes.
-
that's awesome .. what's a good toy QM system for me to work this out in?
- 1 more reply
New conversation -
Loading seems to be taking a while.
Twitter may be over capacity or experiencing a momentary hiccup. Try again or visit Twitter Status for more information.