One possible mechanism for massive neutron star supported by soft EOS

Abstract

The recently discovery of a massive neutron star (PSR J1614-2230 of $1.97\pm 0.04M_{\odot }$) rules out the soft equation of states (EOSs) such as those included hyperons or kaon condensates at high densities, while the nuclear theory or the terrestrial laboratory data prefer a soft EOS. Here we propose one possible mechanism to allow that the observed massive neutron star can be supported by a soft EOS, that is, if the the gravitational constant $G$ varies at super strong field, a soft EOS can support the massive neutron stars.

Comments: 5 pages, 3 figures