Unraveling

An unraveling maps a time-evolved Density Operator ${\rho }_t$ to it’s Quantum state $|{\psi }_S(t)⟩$. Unravellings lose information about Coherences that are only kept in a Density Operator, and as such they might be a poor representation of a quantum system.

Any Master equation $\frac{d}{dt}{\rho }_t=H$ has at least one associated unraveling, and can potentially have infinitely many unravelings. It is unclear if this has been proven. Help me ❓