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Bosh
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Classical Perturbation Theory--Time Dep. vs. Time Indep (Goldstein).
Hi,
I'm going through Goldstein, and I'm a little confused on the distinction between time dependent and time independent perturbation theory. In section 12.2, they do the case of a simple harmonic perturbation on force free motion. I would have thought that the perturbation [itex]\Delta H = \frac{m\omega^2 x^2}{2}[/itex] would not be considered time-dependent. Is the key that when you plug in the unperturbed solution for x, i.e., [itex]\frac{\alpha t}{m} + \beta[/itex], the perturbation hamiltonian is now time-dependent?
If so, it would seem that the example they treat in the section on time-independent perturbation theory, the anharmonic oscillator with [itex]\Delta H = \frac{\epsilon m^2 \omega_0^2 q^3}{q_0}[/itex], could also have been treated as a time-dependent problem.
Any insight would be appreciated! Thanks!
Dan
Hi,
I'm going through Goldstein, and I'm a little confused on the distinction between time dependent and time independent perturbation theory. In section 12.2, they do the case of a simple harmonic perturbation on force free motion. I would have thought that the perturbation [itex]\Delta H = \frac{m\omega^2 x^2}{2}[/itex] would not be considered time-dependent. Is the key that when you plug in the unperturbed solution for x, i.e., [itex]\frac{\alpha t}{m} + \beta[/itex], the perturbation hamiltonian is now time-dependent?
If so, it would seem that the example they treat in the section on time-independent perturbation theory, the anharmonic oscillator with [itex]\Delta H = \frac{\epsilon m^2 \omega_0^2 q^3}{q_0}[/itex], could also have been treated as a time-dependent problem.
Any insight would be appreciated! Thanks!
Dan