Coarse graining nuclear interactions

We consider a coarse graining of NN interactions in coordinate space very much in the spirit of the well known V low k approach. To this end we sample the interaction at about the minimal de Broglie wavelength probed by NN scattering below the pion production threshold. This amounts to providing a simple delta-shell potential plus the standard OPE potential above 2 fm. The possible simplifications in the nuclear many body problem are discussed.