Racines orthogonales et orbites dʹalgèbres de Lie semi-simple graduées Original Research Article

We define a particular class of regular prehomogeneous vector spaces of parabolic type in relation with orthogonal roots, on a field of characteristic 0. We give the structure and the orbits of simple elements associated to the nonzero nilpotent elements of the prehomogeneous vector spaces in terms of these orthogonal roots.