  Neutron star is the ultimate testing place for the physics of dense nuclear
matter. Before the detection of gravitational waves from the merger of binary
neutron stars, various nuclear equations of state have been used to estimate
the macroscopic properties of neutron stars, such as masses and radii, based on
the electromagnetic observations. However, recent observations on the tidal
deformability of neutron star from the gravitational waves GW170817 opened a
new era of multi-messenger astronomy and astrophysics, and many theoretical
works have been extended to estimate the tidal deformability of neutron stars.
In this article, we review our recent works on the application of nuclear
energy density functionals to the properties of neutron stars including tidal
deformability. We found that many nuclear energy density functionals, including
new KIDS (Korea: IBS-Daegu-Sungkyunkwan) model, satisfy both constraints from
current electromagnetic and gravitational wave observations. We discuss future
possibilities of constraining nuclear matter equation of state from
ground-based experiments and multi-messenger observations.
