An analytical relation between center of mass momenta in a nonrelativistic and a relativistic two-nucleon Schrödinger equation is proposed which allows analytically rewriting the two Schrödinger equations into each other. As a consequence a $\mathrm{NN}$ potential occurring in the relativistic Schrödinger equation can be gained from a nonrelativistic one by an analytical procedure. The $S$ matrices in the two equations are exactly identical, and therefore the two-nucleon phase shifts are also.

• Received 18 September 1997

DOI:https://doi.org/10.1103/PhysRevLett.80.2547