On free nets over Minkowski space

Using standard results on CAR- and CCR-theory and on representation theory of the Poincaré group a direct way to construct nets of local C∗-algebras satisfying Haag-Kastlerʹs axioms is given. No explicite use of any field operator or of any concrete representation of the algebra is made. The nets are associated to models of mass m ⩾ 0 and arbitrary spin or helicity. Finally, Fock states satisfying the spectrality condition are specified.