  Taken as a classification paradigm completing the standard model, a new
compact form of the SU(2/1) supergroup explains many mysterious properties of
the weak interactions: the maximal breaking of parity, the fractional charges
of the quarks, the cancellation of the quantum field theory anomalies, and ties
together the existence of the right neutrinos and of the heavier Fermions. This
compact supergroup is constructed by exponentiating the matrices representing
the leptons and the quarks which form a semi-direct sum of Kac modules of the
real superalgebra su(2/1,R) such that the overall trace of the $U(1)$
weak-hypercharge $Y$ vanishes. Remarkably, all the elements of this supergroup
have Berezinian 1 and determinant 1. In practice, $Tr(Y)=0$ simply means that
the electric charge of the hydrogen atom is zero.
