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arXiv · 1007.3511

Constraining the Inflationary Equation of State

Lotty Ackerman·Willy Fischler·Sandipan Kundu·Navin Sivanandam
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Abstract

We explore possible constraints on the inflationary equation state: p=w\rho. While w must be close to -1 for those modes that contribute to the observed power spectrum, for those modes currently out of experimental reach, the constraints on w are much weaker, with only w<-1/3 as an a priori requirement. We find, however, that limits on the reheat temperature and the inflationary energy scale constrain w further, though there is still ample parameter space for a vastly different (accelerating) equation of state between the end of quasi-de Sitter inflation and the beginning of the radiation-dominated era. In the event that such an epoch of acceleration could be observed, we review the consequences for the primordial power spectrum.

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Lotty Ackerman, Willy Fischler, Sandipan Kundu, Navin Sivanandam. 2010-07-20. Constraining the Inflationary Equation of State. https://doi.org/10.1088/1475-7516/2011/05/024

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