Study of degenerate interacting levels by aid of the Liouville equation

Abstract

This study will allow discussion of the steady and time-dependent states describing two degenerate interacting levels in terms of the first moments of the Hamiltonian.

On the use of the adiabaticity concept to obtain approximate solutions of the Schrödinger equation

“…Here we wish to present the method outlined in the preceding section as an alternative way of getting the wave functions and energies of the Schrodinger equation. The advantages of this method over perturbation theory are: (1) In order to get the n order correction to the energy we do not need to evaluate the n -1 correction to the wave function. (2) The method does not include the evaluation of tedious sum over eigenstates.…”

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In a recent article in this Journal Boulil et al have discussed the connection between thermodynamical and quantum mechanical adiabaticity (1). In thermodynamics an adiabatic process is one during which the entropy of the system does not change.

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