Rayleigh scattering (pronounced ), named after the British physicist
Lord Rayleigh (John William Strutt), is the (dominantly)
elastic scattering of
light or other
electromagnetic radiation by particles much smaller than the
wavelength of the radiation. Rayleigh scattering does not change the state of material, hence it is a
parametric process. The particles may be individual atoms or molecules. It can occur when light travels through transparent solids and liquids, but is most prominently seen in
gases. Rayleigh scattering results from the electric
polarizability of the particles. The oscillating electric field of a light wave acts on the charges within a particle, causing them to move at the same frequency. The particle therefore becomes a small radiating dipole whose radiation we see as scattered light.