The Nuclear Physics of Neutron Stars

TL;DR

Neutron stars serve as natural laboratories for studying the equation of state of neutron-rich matter, with their observable properties helping to constrain nuclear interactions under extreme densities.

Contribution

The paper reviews how neutron star observations and experiments can tightly constrain the nuclear equation of state at high densities.

Findings

Neutron stars are sensitive only to the equation of state of neutron-rich matter.

Observables from neutron stars can constrain nuclear interactions under extreme conditions.

Theoretical, experimental, and observational data collectively limit the properties of dense nuclear matter.

Abstract

A remarkable fact about spherically-symmetric neutron stars in hydrostatic equilibrium - the so-called Schwarzschild stars - is that the only physics that they are sensitive to is the equation of state of neutron-rich matter. As such, neutron stars provide a myriad of observables that may be used to constrain poorly known aspects of the nuclear interaction under extreme conditions of density. After discussing many of the fascinating phases encountered in neutron stars, I will address how powerful theoretical, experimental, and observational constraints may be used to place stringent limits on the equation of state of neutron-rich matter.