The derivative of a certain quantity with respect to some parameter is given as the expectation value of the derivative of this operator according the HellmannFeynman theorem.
The derivative of a certain quantity with respect to some parameter is given as the expectation value of the derivative of this operator according the HellmannFeynman theorem. The interaction picture of quantum mechanics expresses this function as a sum of it's free and interaction component. Observables are constants of motion if they commute with this operator, because the time derivative of an operator is proportional to the commutator of that operator with this one, according to the (*) Heisenberg equation. The time evolution operator is the exponential of this operator times negative i t over h-bar. Performing a Legendre transformation on the Lagrangian gives this function, which is potential plus kinetic energy. For 10 points, name this function that represents the total energy of a system.
The derivative of a certain quantity with respect to some parameter is given as the expectation value of the derivative of this operator according the HellmannFeynman theorem.
Hamiltonian