Flavour-coherent propagators and Feynman rules: covariant cQPA formulation

We present a simplified and generalized derivation of the flavour-coherent propagators and Feynman rules for the fermionic kinetic theory based on coherent quasiparticle (cQPA) [1-7]. The new formulation immediately reveals the composite of the cQPA Wightman function as a product of two spectral functions and an effective two-point interaction vertex, which contains all quantum statistical and coherence We extend our previous work to the case of nonzero dispersive self-energy, leads to a broader range of applications. By this scheme, we derive flavoured kinetic for local 2-point functions S-k(<,>) (t, t), which are reminiscent of the equations of for the density matrix. We emphasize that in our approach all the interaction terms derived from first principles of nonequilibrium quantum field theory.