Pure state
= Pure state
{wiki}
A pure quantum state is represented by a unit vector $|\psi\rangle$ up to global phase, or equivalently by the rank-one <density operator> $|\psi\rangle\langle\psi|$.
= Pure state
{wiki}
A pure quantum state is represented by a unit vector $|\psi\rangle$ up to global phase, or equivalently by the rank-one <density operator> $|\psi\rangle\langle\psi|$.