A pseduomixture of states is an affine combination of states, i.e.

ρ = ∑_jr_jρ_j
where ∑_jr_j = 1 and the r_j are real.

This is different from a mixture of states in that for a mixture, the r_j have to be non-negative.

See also

• Mixture

Category:Quantum States Category:Mathematical Structure