Hello, can someone give an example for an incoherent State --> a formula is here on page 7 : http://quantumcorrelations.weebly.com/uploads/6/6/5/5/6655648/2016_robustnessofcoherencetalk.pdf I know that coherenc is e.g. a superposition of e.g. Spin-Up and Spin-Down [z] or so.... But i have no idea about an incoherent state. Is it maybe a "clear" state e.g. Spin-Down [z] (if you measuring Spin [z] you get 100% Spin-Down)? Thanks PS: sorry, bad english. Not my natural language.