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arXiv · 1607.01720

Approximation of the potential in scalar field dark energy models

Richard A. Battye·Francesco Pace
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Abstract

We study the nature of potentials in scalar field based models for dark energy - with both canonical and noncanonical kinetic terms. We calculate numerically, and using an analytic approximation around $a\approx 1$, potentials for models with constant equation-of-state parameter, $w_ϕ$. We find that for a wide range of models with canonical and noncanonical kinetic terms there is a simple approximation for the potential that holds when the scale factor is in the range $0.6\lesssim a\lesssim 1.4$. We discuss how this form of the potential can also be used to represent models with non-constant $w_ϕ$ and, hence, how it could be used in reconstruction from cosmological data.

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Richard A. Battye, Francesco Pace. 2016-10-01. Approximation of the potential in scalar field dark energy models. https://doi.org/10.1103/physrevd.94.063513

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