Cosmological evolution of equation of state for dark energy in G-essence models

Kazuharu Bamba; Olga Razina; Koblandy Yerzhanov; Ratbay Myrzakulov

doi:10.1142/s0218271813500235

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arXiv · 1203.2804

Cosmological evolution of equation of state for dark energy in G-essence models

Kazuharu Bamba·Olga Razina·Koblandy Yerzhanov·Ratbay Myrzakulov

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Abstract

We explore the cosmological evolution of equation of state (EoS) for dark energy in g-essence models, the action of which is described by a function of both the canonical kinetic term of both the scalar and fermionic fields. We examine g-essence models with realizing the crossing of the phantom divide line of $w_{\mathrm{DE}}=-1$ as well as the models in which the universe always stays in the non-phantom (quintessence) phase ($w_{\mathrm{DE}}>-1$). In particular, we find an explicit g-essence model with the crossing from the non-phantom phase to the phantom one ($w_{\mathrm{DE}}<-1$). This transition behavior is consistent with the recent observational data analyses.

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Kazuharu Bamba, Olga Razina, Koblandy Yerzhanov, Ratbay Myrzakulov. 2013-01-31. Cosmological evolution of equation of state for dark energy in G-essence models. https://doi.org/10.1142/s0218271813500235

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