Photosensitivity of optical fibres doped with different impurities

Abstract

The Gell-Mann and Low's technology and Bethe-Salpeter equation for manyparticles are first discussed. Then the space-like form of Bethe-Salpeter equation involving both the bound state and scatter state are extended to many-particle case. Consequently we build the formalism of the space-like equation with explicit Lorentz covariant form and without the difficulty of ghost states automatically PACS numbers: 11.10