Models of F4

We describe the models of the exceptional Lie algebra F4 which are based on its semisimple subalgebras of rank 4. The underlying fact is that the reductive subalgebras of maximal rank of a simple Lie algebra induce a grading on this algebra by means of an abelian group, in such a way that the nontrivial components of the grading are irreducible modules.

C. Draper < cdf@uma.es >