The nuclear force problem: Are we seeing the end of the tunnel?

Abstract

Embedded in the historical context, we review recent progress in the development of nucleon-nucleon (NN) potentials based upon chiral effective field theory. A major breakthrough is the construction of the first NN potential at next-to-next-to-next-to-leading order (fourth order) of chiral perturbation theory (ξPT). The accuracy of this potential concerning the reproduction of the NN data below 290 MeV lab. energy is comparable to the one of phenomenological high-precision potentials. Since NN potentials of order three or less of ξPT are known to be deficient in quantitative terms, the recent advances show that the fourth order of ξPT is necessary and sufficient for a reliable NN potential derived from chiral effective Lagrangians. This recent substantial progress raises hopes that we might be getting closer to a solution of the nuclear force problem at low energies that has plagued the community for more than half a century.