
Physics 1998
The Schrodingerlike Equation for a Nonrelativistic Electron in a Photon Field of Arbitrary IntensityAbstract: The ordinary Schrodinger equation with minimal coupling for a nonrelativistic electron interacting with a singlemode photon field is not satisfied by the nonrelativistic limit of the exact solutions to the corresponding Dirac equation. A Schrodingerlike equation valid for arbitrary photon intensity is derived from the Dirac equation without the weakfield assumption. The "eigenvalue" in the new equation is an operator in a Cartan subalgebra. An approximation consistent with the nonrelativistic energy level derived from its relativistic value replaces the "eigenvalue" operator by an ordinary number, recovering the ordinary Schrodinger eigenvalue equation used in the formal scattering formalism. The Schrodingerlike equation for the multimode case is also presented.
