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arXiv · 0812.3182

Cyclic Inflation

Tirthabir Biswas·Stephon Alexander
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Abstract

We present an inflationary model that is geodesically complete and does not suffer from the transplanckian problem. In most inflationary models, massless (conformal) scalar field fluctuations in a deSitter background gives rise to a scale-invariant spectrum. In this work, we realize scale invariant perturbations from thermal fluctuations in (conformal) radiation during a radiation dominated contraction era prior to inflation. As the modes exit the Hubble radius during the contraction phase, scale invariant fluctuations are indeed generated. After many cycles, we enter into a power-law inflationary phase, that stretches the modes produced in the previous contraction phase to scales that we observe today.

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Tirthabir Biswas, Stephon Alexander. 2008-12-17. Cyclic Inflation. https://doi.org/10.1103/physrevd.80.043511

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