Transport theory of scalar fields for particles with width

For a #phi#"4-theory the equal-time transport theory is derived with a collision term by including 4-point correlations. The necessary information to describe particles with width is obtained from including energy-moments of higher order of both 1-particle correlations. Within a #Planck constant# expansion a set of coupled equations is presented for the first four energy moments of the 1-particle correlations and the 4-point correlations. We show that in this way a dynamical width of the particles is included which is phase-space dependent. The limit #Planck constant# #-># 0 is discussed. The presence of 4-point correlations describing the collision term leads already in this limit to particles with width. (orig.)Available from FIZ Karlsruhe / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman