Quintessential Inflation in a thawing realization

TL;DR

This paper explores a specific inflationary model with an inverse hyperbolic potential, analyzing its compatibility with observational data and its implications for late-time acceleration and reheating mechanisms.

Contribution

It introduces a new inflationary potential, constrains its parameters with Planck data, and discusses its role in late-time acceleration and preheating processes.

Findings

Spectral index and tensor-to-scalar ratio fit Planck 2015 data for certain parameters.

The model can account for late-time cosmic acceleration via neutrino coupling.

Bounds on coupling constants are derived from nucleosynthesis constraints.

Abstract

We study quintessential inflation with an inverse hyperbolic type potential $V(\phi) = {V_0}/{\cosh \left( {\phi^n}/{\lambda^n} \right)}$, where $V_0$, $\lambda$ and "n" are parameters of the theory. We obtain a bound on $\lambda$ for different values of the parameter n. The spectral index and the tensor-to-scalar-ratio fall in the $1 \sigma$ bound given by the Planck 2015 data for $n \geq 5$ for certain values of $\lambda$. However for $3 \leq n < 5$ there exist values of $\lambda$ for which the spectral index and the tensor-to-scalar-ratio fall only within the $2 \sigma$ bound of the Planck data. Furthermore, we show that the scalar field with the given potential can also give rise to late time acceleration if we invoke the coupling to massive neutrino matter. We also consider the instant preheating mechanism with Yukawa interaction and put bounds on the coupling constants for our model using the nucleosynthesis constraint on relic gravity waves produced during inflation.