Can we describe light nuclei without three body forces?

We use the J-matrix version of inverse scattering theory to obtain an interaction to be used in the no-core shell model developed by James Vary and others. Through the J-matrix approach we find a representative of the class of Hamiltonians whose members give the same two-body scattering data. Then we preform phase equivalent transformations to find the two body interaction within this class that best describes light nuclei. We obtain excellent results up to $^{6}$Li and we expect to get good results up to $% ^{16}$O. We have not explicitly introduced three body forces. But the effect of a three body force in a many body system is reproduced by changes of the off shell properties of the $NN$ interaction.