Wigner symmetry, large Nc, and renormalized one-boson exchange potentials

Wigner symmetry in nuclear physics provides a unique example of a nonperturbative medium and long distance symmetry, a symmetry strongly broken at short distances. We analyze the consequences of such a concept within the framework of one-boson exchange potentials in NN scattering and keeping the leading N-c contributions. Phenomenologically successful relations between singlet S-1(0) and triplet S-3(1) scattering phase shifts are provided in the entire elastic region. We establish symmetry breaking relations among noncentral phase shifts which are successfully fulfilled by even-L partial waves and strongly violated by odd-L partial waves, in full agreement with large N-c requirements.