Recent detection of gravitational waves from a binary-neutron star merger (GW170817) and the subsequent observations of electromagnetic counterparts provide a great opportunity to study the physics of compact binary mergers. To extract the physical information from the observation, theoretical modelling for gravitational waveforms and electromagnetic signals is crucial. In this talk, I briefly review the current understanding of neutron star binary mergers and present our recent works for modelling gravitational waves and electromagnetic counterparts based on the latest numerical-relativity and radiative transfer simulations. |