  We propose a theory of the resonance-antiresonance scattering process which
differs considerably from the classical one (the Breit-Wigner theory), which is
commonly used in the phenomenological analysis. Here both resonances and
antiresonances are described in terms of poles of the scattering amplitude: the
resonances by poles in the first quadrant while the antiresonances by poles in
the fourth quadrant of the complex angular momentum plane. The latter poles are
produced by non-local potentials, which derive from the Pauli exchange forces
acting among the nucleons or the quarks composing the colliding particles.
