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arXiv · 1207.3638

Multiple Inflationary Stages with Varying Equation of State

Mohammad Hossein Namjoo·Hassan Firouzjahi·Misao Sasaki
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Abstract

We consider a model of inflation consisting a single fluid with a time-dependent equation of state. In this phenomenological picture, two periods of inflation are separated by an intermediate non-inflationary stage which can be either a radiation dominated, matter dominated or kinetic energy dominated universe, respectively, with the equation of state $w=1/3$, 0 or 1. We consider the toy model in which the change in $w$ happens instantaneously. Depending on whether the mode of interest leaves the horizon before or after or between the phase transitions, the curvature power spectrum can have non-trivial sinusoidal modulations. This can have interesting observational implications for CMB anisotropies and for primordial black-hole formation.

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Mohammad Hossein Namjoo, Hassan Firouzjahi, Misao Sasaki. 2013-03-19. Multiple Inflationary Stages with Varying Equation of State. https://doi.org/10.1088/1475-7516%2F2012%2F12%2F018

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