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arXiv · 1210.3617

Irreversible thermodynamic description of interacting dark energy - dark matter cosmological models

Tiberiu Harko·Francisco S. N. Lobo
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Abstract

We investigate the interaction between dark energy and dark matter in the framework of irreversible thermodynamics of open systems with matter creation/annihilation. We consider dark energy and dark matter as an interacting two component (scalar field and "ordinary" dark matter) cosmological fluid in a homogeneous spatially flat and isotropic Friedmann-Robertson-Walker (FRW) Universe. The thermodynamics of open systems as applied together with the gravitational field equations to the two component cosmological fluid leads to a generalization of the elementary dark energy-dark mater interaction theory, in which the decay (creation) pressures are explicitly considered as parts of the cosmological fluid stress-energy tensor. Specific models describing coherently oscillating scalar waves, leading to a high particle production at the beginning of the oscillatory period, and models with a constant potential energy scalar field are considered. Furthermore, exact and numerical solutions of the gravitational field equations with dark energy-dark matter interaction are also obtained.

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Tiberiu Harko, Francisco S. N. Lobo. 2013-01-28. Irreversible thermodynamic description of interacting dark energy - dark matter cosmological models. https://doi.org/10.1103/physrevd.87.044018

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