Retarded Interaction of Radiation Field and Symmetry Violation of Time Reversal in the High order Stimulated Radiation and Absorption Processes of Light

Abstract

It is proved that when the retarded effect (or multiple moment effect) of radiation fields is taken into account, the high order stimulated radiation and stimulated absorption probabilities of light are not the same so that time reversal symmetry would be violated, though the total Hamiltonian of electromagnetic interaction is still unchanged under time reversal. The reason to cause time reversal symmetry violation is that certain filial or partial transitive processes of bounding state atoms are forbidden or can not be achieved actually due to the law of energy conservation, the asymmetric actions of effective transition operators before and after time reversal, as well as the special states of atoms themselves. These restrictions would cause the symmetry violation of time reversal of other filial or partial transition processes which can be actualized really. The symmetry violation is also relative to the initial state asymmetries of bounding atoms before and after time reversal. For the electromagnetic interaction between non-bounding state atoms and radiation field, there is no this kind of symmetry violation of time reversal. In this way, the current formula of light stimulated radiation and absorption parameters with time reversal symmetry should be revised. The influence of time reversal symmetry violation on the foundational theory of laser is also discussed and the phenomena of non-population inversion and non-radiation transition can also be explained well. In this way, a more reliable foundation can be established for the theories of laser and nonlinear optics in which non-equilibrium processes are involved.