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arXiv · 0812.1502

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

T. C. Lipscombe
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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.

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T. C. Lipscombe. 2008-12-08. Self-gravitating clouds of generalized Chaplygin and modified anti-Chaplygin Gases. https://doi.org/10.1088/0031-8949%2F83%2F03%2F035901

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