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The Spectrum of Fluctuations in Singularity-free Inflationary Quantum Cosmology

S. Hofmann·O. Winkler
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Abstract

We calculate the power spectrum of vacuum fluctuations of a generic scalar field in a quantum cosmological setting that is manifestly singularity-free. The power spectrum is given in terms of the usual scale invariant spectrum plus scale dependent corrections. These are induced by well-defined quantum fluctuations of de Sitter spacetime, resulting in a modified dispersion relation for the scalar field. The leading correction turns out to be proportional to the ratio of Hubble scale and Planck Mass. The maximal relative change in the spectrum is on the ten percent level and might be observable with future CMB experiments.

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S. Hofmann, O. Winkler. 2005-11-28. The Spectrum of Fluctuations in Singularity-free Inflationary Quantum Cosmology. https://arxiv.org/abs/astro-ph/0411124

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