Dissipative generalized Chaplygin gas as phantom dark energy

TL;DR

This paper explores dissipative effects in generalized Chaplygin gas models of dark energy, finding analytical solutions that can cross the phantom divide and introduce new types of future singularities.

Contribution

It introduces dissipative processes into generalized Chaplygin gas models using relativistic thermodynamics, enabling crossing of the phantom divide and identifying novel future singularities.

Findings

Analytical solutions with dissipation are derived.

Models can cross the w=-1 barrier.

New types of future singularities are identified.

Abstract

The generalized Chaplygin gas, characterized by the equation of state $p=-\mathcal{A}/\rho^{\alpha}$, has been considered as a model for dark energy due its dark-energy-like evolution at late times. When dissipative processes are taken account, within the framework of the standard Eckart theory of relativistic irreversible thermodynamics, cosmological analytical solutions are found. Using the truncated causal version of the Israel-Stewart formalism, a suitable model was constructed which cross the $w=-1$ barrier. The future-singularities encounter in both approaches are of a new type, not included in the classification presented by S. Nojiri, S. D. Odintsov and S. Tsujikawa, Phys. Rev. D71, 063004 (2005).