  We discuss the inclusion of relativistic boost corrections into the CBF
effective nuclear Hamiltonian, derived from a realistic model of two- and
three-nucleon interactions using the formalism of correlated basis functions
and the cluster expansion technique. Different procedures to take into account
the effects of boost interactions are compared on the basis of the ability to
reproduce the nuclear matter equation of state obtained from accurate many-body
calculations. The results of our study show that the repulsive contribution of
the boost interaction significantly depends on the underlying model of the non
relativistic potential. On the other hand, the dominant relativistic correction
turns out to be the corresponding reduction of the strength of repulsive
three-nucleon interactions, leading to a significant softening of the equation
of state at supranuclear densities.
