  Role of the isospin asymmetry in nuclei and neutron stars, with an emphasis
on the density dependence of the nuclear symmetry energy, is discussed. The
symmetry energy is obtained using the isoscalar as well as isovector components
of the density dependent M3Y effective interaction. The constants of density
dependence of the effective interaction are obtained by reproducing the
saturation energy per nucleon and the saturation density of spin and isospin
symmetric cold infinite nuclear matter. Implications for the density dependence
of the symmetry energy in case of a neutron star are discussed, and also
possible constraints on the density dependence obtained from finite nuclei are
compared.
