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The path integral — all paths, e^(iS/ℏ), the classical one by interference
lagrangian
Feynman: a quantum system takes ALL paths, each weighted by e^(iS/hbar); they interfere, and where the action is stationary the phases reinforce (the classical path), elsewhere they cancel; as hbar -> 0 only the least-action path survives. The many paths are real; the one emerges by interference. Sealed on stick_the_principle_of_least_action.
source
Narrow Highway — the Lagrangian
card id
card_lag_path_integral
address
WIT.codex.FCT/the-path-integral-all-paths-e-is-the-classical-o/REF.WITNESSED@narrow-highway
adjoining cards
- part of → The Lagrangian — the Hamiltonian's dual, the path chosen — a pillar of the Lagrangian (The path integral)
- connects at → The capstone — one source, many potentials, one end — the many paths are real; the classical one emerges by interference
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