Approximation methods for stationary solutions of discrete master equations

Two methods for finding stationary solutions of discrete master equation in general cases without detailed balance are set up and compared for the case of the Laser equation. The first method starts from a reduced master equation obtained for appropriate forms of the Liouvillean, the second from a variational principle for the stationary solution of the full master equation. In the Laser case, both methods lead to forms of the stationary solution essentially equivalent to the result of Dohm.