MIXTURES AND PURE STATES IN RELATIVISTIC SCHRODINGER-THEORY

In relativistic Schrodinger theory, a physical system can be described by a wave function (squiggly arrow pointing right ''pure state'') or by an intensity matrix (squiggly arrow pointing right ''mixture''). Si nce the space-time evolution of the system is described by a non-Hermi tian Hamiltonian, transmutations of mixtures into pure states (and vic e versa) would be formally possible. Nevertheless, the transition of a mixture into a pure state is dynamically forbidden, whereas the pure states are unstable and decay into mixtures. This effect is demonstrat ed by considering the Klein-Gordon-Higgs equations over an expanding R obertson-Walker universe.