Upper-bound nature of the Brueckner energy of nuclear matter

Abstract

A trial wavefunction is constructed for nuclear matter in terms of the reaction matrix. The trial function includes only two-particle excitations and the resulting energy expectation value for two-nucleon forces with a state-independent repulsive core of Yukawa shape approaches in the thermodynamic limit the energy given by the lowest-order Brueckner theory with standard dispersion. Evaluation of the energy expectation value is carried out in a systematic way by use of an identity that holds between the Hamiltonian and reaction matrix.