Ground state energy of a many-particle boson system

A trial expression for the ground state energy of a system of many bosons interacting with strong forces is studied. Using an approximate expression for the pair-distribution function and applying the variational principle in an appropriate way, we obtain a non-linear integrodifferential equation for the correlation functionf(r). This equation is subsequently linearised and its behaviour for large separations is studied. It is also shown that for large separations an effective reduced mass of the pair can be defined. This is given by^*=2, where=m/2 is the reduced mass of the pair.