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arXiv · 1809.09274

Stealth's cosmologies

Abigail Alvarez·Cuauhtemoc Campuzano·Víctor Cárdenas·Efraín Rojas
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Abstract

We present a novel approach to construct cosmological models endowed with a particular scalar field, the stealth. The model is constructed by studying a scalar field no-minimally coupled to the gravitational field with sources; as sources, we used a perfect fluid and analyzed the simplest case of dust and the power-law cosmology. Surprisingly, we find that these stealth fields, which have no back-reaction to background space-time, have a contribution to cosmological dynamics. Furthermore, we provide analytic expressions of the stealth's contributions to the energy density in both cases, and for the pressure in the power-low cosmology, which means that such contributions to cosmological evolution are quantifiable. Additionally, we discuss the behaviors of the self-interaction potential for some cases.

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Abigail Alvarez, Cuauhtemoc Campuzano, Víctor Cárdenas, Efraín Rojas. 2018-09-25. Stealth's cosmologies. https://arxiv.org/abs/1809.09274

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