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arXiv · hep-th/0610054

Inflation without Inflaton(s)

Scott Watson·Malcolm J. Perry·Gordon L. Kane·Fred C. Adams
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Abstract

We propose a model for early universe cosmology without the need for fundamental scalar fields. Cosmic acceleration and phenomenologically viable reheating of the universe results from a series of energy transitions, where during each transition vacuum energy is converted to thermal radiation. We show that this `cascading universe' can lead to successful generation of adiabatic density fluctuations and an observable gravity wave spectrum in some cases, where in the simplest case it reproduces a spectrum similar to slow-roll models of inflation. We also find the model provides a reasonable reheating temperature after inflation ends. This type of model may also be relevant for addressing the smallness of the vacuum energy today.

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Scott Watson, Malcolm J. Perry, Gordon L. Kane, Fred C. Adams. 2008-05-08. Inflation without Inflaton(s). https://doi.org/10.1088/1475-7516%2F2007%2F11%2F017

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