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arXiv · 1008.4567

Dynamical Selection of the Primordial Density Fluctuation Amplitude

Jean-Luc Lehners·Paul J. Steinhardt
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Abstract

In inflationary models, the predicted amplitude of primordial density perturbations Q is much larger than the observed value (~10^{-5}) for natural choices of parameters. To explain the requisite exponential fine-tuning, anthropic selection is often invoked, especially in cases where microphysics is expected to produce a complex energy landscape. By contrast, we find examples of ekpyrotic models based on heterotic M-theory for which dynamical selection naturally favors the observed value of Q.

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Jean-Luc Lehners, Paul J. Steinhardt. 2011-02-18. Dynamical Selection of the Primordial Density Fluctuation Amplitude. https://doi.org/10.1103/physrevlett.106.081301

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