query: How is Schwinger's quantum action principle related to least action?
positive_passages.docid: 151173
positive_passages.text: Is the quantum action principle of Schwinger a variational principle?
negative_passages.docid: 147524
negative_passages.text: Why is the "canonical momentum" for the Dirac equation not defined in terms of the "gauge covariant derivative"?
negative_passages.docid: 79647
negative_passages.text: Where does the term $|\psi\rangle\langle\psi|$ come from while calculating the expectation value?
negative_passages.docid: 158526
negative_passages.text: Finding a "Principle of Least Action" equivalent statement for Hamiltonian Mechanics
negative_passages.docid: 86967
negative_passages.text: The concept of particle in QFT
negative_passages.docid: 90852
negative_passages.text: Does Action in Classical Mechanics have a Interpretation?
negative_passages.docid: 132834
negative_passages.text: Trying to understand relativistic action of a massive point particle
negative_passages.docid: 18414
negative_passages.text: Energy-Momentum Tensor in QFT vs. GR
negative_passages.docid: 77761
negative_passages.text: Arrow and flow of charge in fermion propagator
negative_passages.docid: 48930
negative_passages.text: Least-action classical electrodynamics without potentials
negative_passages.docid: 38103
negative_passages.text: A No-Nonsense Introduction to Quantum Field Theory
negative_passages.docid: 26085
negative_passages.text: Why is the action dimensionless in natural units?
negative_passages.docid: 12422
negative_passages.text: Derivation of $E=pc$ for a massless particle?
negative_passages.docid: 58445
negative_passages.text: What does the Canonical Commutation Relation (CCR) tell me about the overlap between Position and Momentum bases?
negative_passages.docid: 101888
negative_passages.text: Least action principle : is $ \delta \frac{dx}{dt} = \frac{d \delta x}{dt} $ always true?
negative_passages.docid: 44843
negative_passages.text: What is the difference between $|0\rangle $ and $0$?
negative_passages.docid: 99063
negative_passages.text: Einstein-Hilbert action as an effective field theory