POSSIBILITY OF GEOMETRIC DESCRIPTION OF QUASI-PARTICLES IN SOLIDS

New phenomenological approach for the description of elementary collec tive excitations is proposed. The crystal is considered to be an aniso tropic space-time vacuum with a prescribed metric tensor in which the information on electromagnetic crystalline fields is included. The qua siparticles in this space are supposed to be described by the equation s structurally similar to the relativistic wave equations for particle s in empty space. The generalized Klein-Gordon-Fock equation and the g eneralized Dirac equation in external electromagnetic field are consid ered. The applicability of the proposed approach to the case of conduc tion electron in a crystal is discussed.