Equation of states in the curved spacetime of spherical degenerate stars

TL;DR

This paper demonstrates that equations of state for spherical degenerate stars must account for curved spacetime effects, as neglecting these leads to significant underestimation of their mass limits.

Contribution

It introduces the dependence of equations of state on the metric function in curved spacetime, highlighting the importance of gravitational effects in modeling compact stars.

Findings

Equation of states depend explicitly on the metric function.

Ignoring metric effects underestimates star mass limits.

Proper inclusion of curvature effects alters star stability predictions.

Abstract

In the study of spherical degenerate stars such as neutron stars, general relativistic effects are incorporated by using Tolman-Oppenheimer-Volkoff equations to describe their interior spacetime. However, the equation of states employed in such studies are invariably computed in flat spacetime. We show that the equation of states computed in the curved spacetime of these stars depend explicitly on the metric function. Further, we show that ignoring such metric-dependent gravitational time dilation effect leads one to grossly underestimate the mass limits of these compact stars.