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Unified Model for Dark Energy

Pedro F. Gonzalez-Diaz
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Abstract

A new model for the universe filled with a generalized Chaplygin fluid is considered which unitarily describes as a single vacuum entity both a quintessence scalar field and a cosmological constant, so unifying the notion of dark energy. While the evolution of the universe filled with such a fluid does not obviously contradict the present cosmic acceleration, the introduced single dark-energy component, for equations of state with characteristic parameter $ω\geq -1$, behaves like an usual quintessence fluid with constant equation of state at early high densities, and like a pure cosmological constant at late cosmological times.

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Pedro F. Gonzalez-Diaz. 2003-02-04. Unified Model for Dark Energy. https://doi.org/10.1016/s0370-2693(03)00540-9

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