11. This is described by a density matrix . 12. Where P is the density matrix . 13. The total state of the system is assumed to be described by a density matrix ?. 14. One of these is the use of the density matrix , and its associated master equation. 15. Therefore, for a J = 1 system, its density matrix must have quadrupole components. 16. The reduced density matrix also was evaluated for XY spin chains, where it has full rank. 17. The conditions for the evolution of the system density matrix to be described by the master equation are: 18. Here \ rho represents the initial density matrix , and the operators are expressed in the Heisenberg picture. 19. For a collapse operator C, the Lindblad superoperator, acting on the density matrix \ rho, is 20. It is formulated in the density matrix formalism and can be regarded a generalization of the Master equation.
