Instantons in the field strength approach to QCD

An approach is presented which treats the gluon self-interaction in a non-perturbative way from the very beginning, but which at the same time is sufficiently simple so that most of the calculations can be done analytically. Field strength formulated Yang-Mills theory is confronted to the traditional formulation in terms of gauge fields. It is shown that both formulations yield the same semiclassics, in particular the same instanton physics. A new class of SU(N) instantons is presented which are not embeddings of SU(N-1) instantons but have non-trivial SU(N) color structure and carry winding number n=N(N2-1)/6. These novel instantons generate (after condensation) the lowest action homogeneous solutions of the field strength approach. (K.A.) 22 refs., 2 figs