Exceptional quantum algebra for the standard model of particle physics

Abstract: The exceptional euclidean Jordan algebra of 3x3 hermitian octonionic matrices, appears to be tailor made for the internal space of the three generations of quarks and leptons. The maximal rank subgroup of its automorphism group F4 that respects the lepton-quark splitting is the product of the colour SU(3) with an "electroweak" SU(3) factor. Its intersection with the automorphism group Spin(9) of the special Jordan subalgebra J, associated with a single generation of fundamental fermions, is precisely the symmetry group S(U(3)xU(2)) of the Standard Model. The Euclidean extension of J involves 32 primitive idempotents giving the states of the first generation fermions. The triality relating left and right Spin(8) spinors to 8-vectors corresponds to the Yukawa coupling of the Higgs boson to quarks and leptons.