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arXiv · 2011.09155

A paradigm of warm quintessential inflation and production of relic gravity waves

Abstract

We consider the framework of quintessential inflation in the warm background which is caused by the dissipation of the scalar field energy density into relativistic degrees of freedom. The dissipation process has important consequences for the evolution both at the levels of background as well as perturbation and allows us to easily satisfy the observational constraints.~Our numerical analysis confirms that the model conforms to observational constraints even if the field-radiation coupling strength is weak. In the warm background, we investigate the post inflationary evolution of relic gravity waves produced during inflation whose amplitude is constrained by the Big Bang Nucleosynthesis constraint. Further, we investigate the effect of coupling on the amplitude of gravity waves and obtain the allowed phase space between the model parameters. The mechanism of quintessential inflation gives rise to the blue spectrum of gravitational wave background at high frequencies. We discuss the perspectives of detection of the signal of relic gravity waves by future proposed missions. Improvements of their sensitivities in the high-frequency regime, in the future, might allow us to probe the blue tilt of the spectrum caused by the presence of a kinetic regime in the underlying framework of inflation.

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Mayukh R. Gangopadhyay, Shynaray Myrzakul, Mohammad Sami, Mohit K. Sharma. 2020-11-18. A paradigm of warm quintessential inflation and production of relic gravity waves. https://doi.org/10.1103/physrevd.103.043505

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