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arXiv · 1103.1533

Quintom scalar field : Varying dark energy equation of state obtained from recent SNe Ia, BAO and OHD data

Debabrata Adak·Abhijit Bandyopadhyay·Debasish Majumdar
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Abstract

From the analysis of Supernova Ia data alongwith Observational Hubble Data (OHD) and Baryon Acoustic Oscillation (BAO) data, we attempt to find out the nature of a scalar potential that may be responsible for the Dark Energy of the universe. We demonstrate that in order to explain the varying dark energy equation of state ($ω_X(z)$) as obtained in a model independent way from the analyses of observational data, we need to invoke a quintom scalar field having a "quintessence" part for $ω_X(z) > -1$ and a "phantom" part for $ω_X(z) < -1$. We consider a Gaussian type potential for these scalar fields and compare the dark energy equation of state derived from such potential with the one computed from the data analysis.

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Debabrata Adak, Abhijit Bandyopadhyay, Debasish Majumdar. 2013-01-10. Quintom scalar field : Varying dark energy equation of state obtained from recent SNe Ia, BAO and OHD data. https://arxiv.org/abs/1103.1533

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