Constellations and projective classical groups

  title={Constellations and projective classical groups},
  author={Henri Bacry},
  journal={Communications in Mathematical Physics},
The constellation concept is recalled (geometrical description of a ray in a vector space). The groups PO(n+1, ℂ) orP Sp(n+1, ℂ) are shown to preserve “harmonic conjugation” between two constellations. The action of the Lorentz subgroup and its rotation subgroup is described. Finally, a theorem concerning Clebsch-Gordan product of constellations is proved.