Classical and quantum Malus laws
Krzysztof Wódkiewicz · Physical Review A · 1995
The classical and the quantum Malus laws for light and spin are discussed. It is shown that for spin 1/2, the quantum Malus law is equivalent in form to the classical Malus law provided the statistical average involves a quasidistribution function that can become negative. A generalization of Malus's law for arbitrary spin s is obtained in the form of a Feynman path-integral representation for the Malus amplitude. The classical limit of the Malus amplitude for s\ensuremath{\rightarrow}\ensuremath{\infty} is discussed.