Neutron stars as extreme laboratories for gravity tests

TL;DR

Neutron stars serve as natural laboratories for testing strong-field gravity and understanding dense nuclear matter, with pulsar timing and gravitational waves playing key roles in these investigations.

Contribution

The paper discusses methods to distinguish gravity effects from nuclear matter properties using universal relations and highlights future research directions.

Findings

Pulsar timing and gravitational wave observations enable precise measurements of neutron star systems.

Universal relations help break degeneracies between gravity tests and nuclear matter equations of state.

Future prospects include advanced observational techniques and theoretical models.

Abstract

Neutron stars are versatile in their application to studying various important aspects of fundamental physics, in particular strong-field gravity tests and the equation of state for super-dense nuclear matter at low temperatures. However, in many cases these two objectives are degenerate to each other. We discuss how pulsar timing and gravitational waves provide accurate measurements of neutron star systems and how to effectively break the degeneracy using tools like universal relations. We also present perspectives on future opportunities and challenges in the field of neutron star physics.