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arXiv · 1301.4746

On the self-interaction of dark energy in a ghost-condensate model

Gour Bhattacharya·Pradip Mukherjee·Anirban Saha
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Abstract

In a ghost-condensate model of dark energy the combined dynamics of the scalar field and gravitation is shown to impose non-trivial restriction on the self-interaction of the scalar field. Using this restriction we show that the choice of a zero self-interaction leads to a situation too restrictive for the general evolution of the universe. This restriction, obtained in the form of a quadratic equation of the scalar potential, is demonstrated to admit real solutions. Also, in the appropriate limit it reproduces the potential in the phantom cosmology.

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Gour Bhattacharya, Pradip Mukherjee, Anirban Saha. 2013-01-21. On the self-interaction of dark energy in a ghost-condensate model. https://arxiv.org/abs/1301.4746

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