A Deep Learning Approach to Extracting Nuclear Matter Properties from Neutron Star Observations

Understanding the equation of state of dense QCD matter remains a major challenge in both nuclear physics and astrophysics. Neutron star observations from electromagnetic and gravitational wave spectra provide critical insights into the behavior of dense neutron-rich matter. The next generation of telescopes and gravitational wave observatories will offer even more detailed observations of neutron stars. Utilizing deep learning techniques to map neutron star mass and radius observations to the equation of state allows for its accurate and reliable determination. This work demonstrates the feasibility of using deep learning to extract the equation of state directly from neutron star observational data, and to also obtain related nuclear matter properties such as the slope, curvature, and skewness of the nuclear symmetry energy at saturation density. Most importantly, we show that this deep learning approach is able to reconstruct \textit{realistic} equations of state, and deduce \textit{realistic} nuclear matter properties. This highlights the potential of artificial neural networks in providing a reliable and efficient means to extract crucial information about the equation of state and related properties of dense neutron-rich matter in the era of multi-messenger astrophysics.