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arXiv · hep-ph/0701213

Couplings and spectra in modular inflation

Wan-Il Park·Ewan D. Stewart
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Abstract

We analyze how the spectrum of perturbations produced in a multi-component modular inflation model proposed by Kadota and Stewart depends on couplings between the two moduli. Although some simple direct couplings give essentially the same results as the original model, $dn/d\ln k \propto n-1$, simple indirect couplings produce a power law spectrum, $n-1 = \textrm{constant}$, which can naturally be close to scale invariant.

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Wan-Il Park, Ewan D. Stewart. 2007-06-06. Couplings and spectra in modular inflation. https://doi.org/10.1103/physrevd.77.023535

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