Superoperator master equations for depolarizing dynamics

The work is devoted to superoperator master equations. Namely, the superoperator master equations in the case of the twirling hyperprojector with respect to the whole unitary group are derived. To be consistent with such a hyperprojector the free dynamics is assumed to be depolarizing. And it is perturbed by the arbitrary Gorini–Kossakowski–Sudarshan–Lindblad generator. The explicit form of the second order master equations are presented in this case.