William Newton, Assistant Professor, Texas A&M University
Several hundred meters beneath the surface of neutron stars, deep in their inner crust, a layer of nuclear soft condensed matter - so-called nuclear pasta - is predicted to mediate the transition to the star's liquid core. Remarkably, signatures of these exotic phases of dense matter may be present in current and future astrophysical observables: the neutrino signal during the cataclysmic birth of the star, the spin-down behavior of young and adolescent neutron stars, the giant gamma-ray flares of magnetars, the cooling of accretion-heated crusts, and persistent gravitational wave signals generated by "mountains" on the surface and oscillations inside of neutron stars.
We will show that, despite the considerable theoretical uncertainties that remain in describing bulk nuclear matter, a significant layer of nuclear pasta in the neutron star crust is a robust prediction. We review current efforts to model the complex, multi-scale physics of the crust-core transition, including detailed 3D quantum simulations of nuclear pasta and current and future efforts aimed at deriving reliable material properties of the deep crust, required to extract information from observations.