arXiv subjects
Publications and source records attributed to L. G. Boussiakou.
We outline the solution of a fundamental problem in quantum theory which has hitherto lacked a proper solution, namely finding the requisite quantum theoretical framework guaranteeing that the calculated inverse spontaneous emission rate of a moving atom, as a composite system of charged particles interacting with the Maxwell field, is slowed down exactly as in time dilation.
The Hamiltonian of a moving atom in electromagnetic fields includes velocity- dependent terms. We show that the leading velocity dependence emerges systematically in the non-relativistic limit from a scheme firmly based on the relativistic invariance of the energy-momentum stress tensor of the coupled matter-fields system. We then extend the Hamiltonian to the many-body situation suitable for describing a Bose-Einstein condensate (BEC). From first principles, we use the equation of motion for the condensate wavefunction to obtain an extended version of the Gross-Pitaevskii (GP) equation and an equation for the internal states of the atoms. It is shown that laser fields modify the GP equation by inclusion of convective terms involving a Rontgen interaction plus a term coupling the centre of mass momentum to the Poynting vector. We also obtain the modified Maxwell equations for the electromagnetic fields coupled to the BEC involving the average velocity of the atoms.