  We discuss the relativistic nuclear equation of state (EOS) using a
relativistic transport model in heavy-ion collisions. From the baryon flow for
$Au + Au$ systems at SIS to AGS energies and above we find that the strength of
the vector potential has to be reduced moderately at high density or at high
relative momenta to describe the flow data at 1-10 A GeV. We use the same
dynamical model to calculate the nuclear EOS and then employ this to calculate
the gross structure of the neutron star considering the core to be composed of
neutrons with an admixture of protons, electrons, muons, sigmas and lambdas at
zero temperature. We then discuss these gross properties of neutron stars such
as maximum mass and radius in contrast to the observational values.
