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arXiv · 1509.02399

A Jacobian generalization of the pseudo Nambu-Goldstone bosons potential

W. S. Hipólito-Ricaldi·J. R. Villanueva
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Abstract

We enlarge the classes of inflaton and quintessence fields by generalizing the pseudo Nambu--Goldstone boson potential by means of elliptic Jacobian functions, which are characterized by a parameter $k$. We use such a generalization to implement an inflationary era and a late acceleration of the universe. As an inflationary model the Jacobian generalization leads us to a number of e-foldings and a primordial spectrum of perturbations compatible with the {\it Planck collaboration} 2015. As a quintessence model, a study of the evolution of its equation of state (EoS) and its $w'$--$w$ plane helps us to classify it as a thawing model. This allows us to consider analytical approximations for the EoS recently discovered for thawing quintessence. By using JLA Supernovae Ia and Hubble parameter $H(z)$ data sets, we perform an observational analysis of the viability of the model as quintessence.

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W. S. Hipólito-Ricaldi, J. R. Villanueva. 2016-07-07. A Jacobian generalization of the pseudo Nambu-Goldstone bosons potential. https://doi.org/10.1142/s0218271817500195

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