%0 Journal Article %A Luis Aina, Alfredo %T Ensemble approach to coherence between two scalar harmonic light vibrations and the phase difference %D 2009 %@ 1050-2947 %U https://hdl.handle.net/20.500.14352/44646 %X We develop an approach to coherence between two scalar harmonic light vibrations derived from the ensemble interpretation of statistical optics. Coherence is presented as a statistical variable itself that turns out to be the phase difference between the two vibrations. This provides a natural and simple extension of second-order coherence to cover more complicated situations. This includes in a single formalism both classic and quantum light states, allowing the most accurate interferometric measurements, even if they are incoherent according to the standard second-order approach. %~