Bose–Einstein correlations

In physics, Bose–Einstein correlations are correlations between identical bosons. They have important applications in astronomy, optics, particle and nuclear physics. In physics, Bose–Einstein correlations are correlations between identical bosons. They have important applications in astronomy, optics, particle and nuclear physics. The interference between two (or more) waves establishes a correlation between these waves. In particle physics, in particular, where to each particle there is associated a wave, we encounter thus interference and correlations between two (or more) particles, described mathematically by second or higher order correlation functions. These correlations have quite specific properties for identical particles. We then distinguish Bose–Einstein correlations for bosons and Fermi–Dirac correlations for fermions. While in Fermi–Dirac second order correlations the particles are antibunched, in Bose–Einstein correlations (BEC) they are bunched. Another distinction between Bose–Einstein and Fermi–Dirac correlation is that only BEC can present quantum coherence (cf. below).