title: Analog of the wigner-moyal equation for the electromagnetic field
abstract: The evolution equation for the Wigner distribution of the classical electromagnetic field is derived for a nonstationary and inhomogeneous optical medium, which is formally similar to the Wigner-Moyal equation for a quantum system. The geometric optics approximation is discussed in detail, and the conservation equation for the number of photons is justified. The influence of dispersion is also considered.
authors.affiliation: Instituto Superior Tecnico, Avenida Rovisco Pais, 1049-001 Lisboa, Portugal.
authors.initials: JT
authors.lastname: Mendonca
authors.initials: NL
authors.lastname: Tsintsadze