  After a brief discussion of the meaning of the potential in quantum
mechanics, we examine the results of the Yukawa model (scalar meson exchange)
for the nucleon-nucleon interaction in three different dynamical frameworks:
the non-relativistic dynamics of the Schrodinger equation, the relativistic
quantum mechanics of the Bethe-Salpeter and Light-Front equations and the
lattice solution of the Quantum Field Theory, obtained in the quenched
approximation.
