A new equation of state for dark energy

Dragan Slavkov Hajdukovic

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arXiv · 0711.0439

A new equation of state for dark energy

Dragan Slavkov Hajdukovic

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Abstract

In the contemporary Cosmology, dark energy is modeled as a perfect fluid, having a very simple equation of state: pressure is proportional to dark energy density. As an alternative, I propose a more complex equation of state, with pressure being function of three variables: dark energy density, matter density and the size of the Universe. One consequence of the new equation is that, in the late-time Universe, cosmological scale factor is linear function of time; while the standard cosmology predicts an exponential function.The new equation of state allows attributing a temperature to the physical vacuum, a temperature proportional to the acceleration of the expansion of the Universe. The vacuum temperature decreases with the expansion of the Universe, approaching (but never reaching) the absolute zero.

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Dragan Slavkov Hajdukovic. 2009-11-04. A new equation of state for dark energy. https://arxiv.org/abs/0711.0439

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