Solving the relativistic inverse stellar problem through gravitational waves observation of binary neutron stars

TL;DR

This paper demonstrates that gravitational wave observations of binary neutron star mergers can effectively constrain the neutron star equation of state by reconstructing stellar parameters through Bayesian inference on simulated data.

Contribution

It introduces a method to use gravitational wave signals to solve the inverse stellar problem, enabling EoS parameter estimation and model selection from GW data.

Findings

Few detections can tightly constrain EoS parameters

Bayesian inference effectively reconstructs stellar properties

Model selection among realistic EoS is feasible

Abstract

The LIGO/Virgo collaboration has recently announced the direct detection of gravitational waves emitted in the coalescence of a neutron star binary. This discovery allows, for the first time, to set new constraints on the behavior of matter at supranuclear density, complementary with those coming from astrophysical observations in the electromagnetic band. In this paper we demonstrate the feasibility of using gravitational signals to solve the relativistic inverse stellar problem, i.e. to reconstruct the parameters of the equation of state (EoS) from measurements of the stellar mass and tidal Love number. We perform Bayesian inference of mock data, based on different models of the star internal composition, modeled through piecewise polytropes. Our analysis shows that the detection of a small number of sources by a network of advanced interferometers would allow to put accurate bounds on the EoS parameters, and to perform a model selection among the realistic equations of state proposed in the literature.