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Density Spectrums from Kinetic Inflations

J. Hwang·H. Noh
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Abstract

The pole-like accelerated expansion stages purely driven by the coupling between the gravity and the dilaton field without referring to the potential term can be realized in a class of generalized gravity theories. We consider three such scenarios based on the scalar-tensor gravity, the induced gravity and the string theory. Quantum fluctuations during the expansion stages (including more general situations) can be derived in exact analytic forms. Assuming that the pole-like acceleration stage provides a viable inflation scenario in the early universe we derive the generated classical density spectrums. The generated classical density field shows a generic tilted spectrum with $n \simeq 4$ which differs from the observed spectrum supporting $n \simeq 1$.

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J. Hwang, H. Noh. 1996-12-30. Density Spectrums from Kinetic Inflations. https://arxiv.org/abs/gr-qc/9612065

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