Gravitational Vacuum Condensate Stars

TL;DR

This paper proposes a new stable gravitational object called a gravitational vacuum condensate star, which replaces black holes by avoiding singularities and horizons, and has distinct thermodynamic properties.

Contribution

It introduces a novel gravitational collapse endpoint modeled as a Bose-Einstein condensate with a shell, differing from classical black holes in structure and entropy.

Findings

No singularities or event horizons in the solution

The entropy is given by the shell's hydrodynamic entropy, not Bekenstein-Hawking

The object is thermodynamically stable and resolves the information paradox

Abstract

A new final state of gravitational collapse is proposed. By extending the concept of Bose-Einstein condensation to gravitational systems, a cold, dark, compact object with an interior de Sitter condensate $p_{_V} = -\rho_{_V}$ and an exterior Schwarzschild geometry of arbitrary total mass $M$ is constructed. These are separated by a shell with a small but finite proper thickness $\ell$ of fluid with equation of state $p=+\rho$, replacing both the Schwarzschild and de Sitter classical horizons. The new solution has no singularities, no event horizons, and a global time. Its entropy is maximized under small fluctuations and is given by the standard hydrodynamic entropy of the thin shell, which is of order $k_{_B}\ell Mc/\hbar$, instead of the Bekenstein-Hawking entropy formula, $S_{_{BH}}= 4\pi k_{_B} G M^2/\hbar c$. Hence unlike black holes, the new solution is thermodynamically stable and has no information paradox.