Self-gravitating clouds of generalized Chaplygin and modified anti-Chaplygin Gases

TL;DR

This paper derives equations for self-gravitating relativistic Chaplygin and modified anti-Chaplygin gases, analyzing their potential to form compact objects and exploring their cosmological implications.

Contribution

It provides the first detailed equations and solutions for self-gravitating relativistic Chaplygin gases and examines the cosmology of a modified anti-Chaplygin gas.

Findings

Mass-radius relationship suggests potential for compact objects in the phantom regime.

Self-gravitating anti-Chaplygin clouds are exact solutions to Einstein's equations.

Modified anti-Chaplygin gas has notable cosmological implications.

Abstract

The Chaplygin gas has been proposed as a possible dark energy, dark matter candidate. As a working fluid in a Friedmann-Robertson-Walker universe, it exhibits early behavior reminiscent of dark matter, but at later times is more akin to a cosmological constant. In any such universe, however, one can expect local perturbations to form. Here we obtain the general equations for a self-gravitating relativistic Chaplygin gas. We solve these equations and obtain the mass-radius relationship for such structures, showing that only in the phantom regime is the mass-radius relationship large enough to be a serious candidate for highly compact massive objects at the galaxy core. In addition, we study the cosmology of a modified anti-Chaplygin gas. A self-gravitating cloud of this matter is an exact solution to Einstein's equations.