Search for extremals of a functional S[q] = ∫ L dt; stationarity δS=0 yields the Euler–Lagrange equations. Underlies Lagrangian/Hamiltonian mechanics, classical field theory, path integrals, and Ritz/finite-element approximations.
Search for extremals of a functional S[q] = ∫ L dt; stationarity δS=0 yields the Euler–Lagrange equations. Underlies Lagrangian/Hamiltonian mechanics, classical field theory, path integrals, and Ritz/finite-element approximations.