Two-particle Greenʹs functions in non-equilibrium matter

The method of derivation of two-particle Greenʹs functions in the non-equilibrium matter has been developed. The closed set of equations for the vertex functions, as well as for the two-particle Greenʹs functions, is obtained by means of the summation of the series of indecomposable diagrams. The solution of such equations completely determines the two-particle Greenʹs functions in the matter.