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Constraints on a scale invariant power spectrum from superinflation in LQC

D. J. Mulryne·N. J. Nunes
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Abstract

The computation of the spectrum of primordial perturbations, generated by a scalar field during the super-inflationary phase of Loop Quantum Cosmology, is revisited. The calculation is performed for two different cases. The first considers the dynamics of a massless field and it is found that scale invariance can only be achieved under a severe fine tuning. The second assumes that the field evolves with a constant ratio between kinetic and potential energy, i.e. in a scaling solution. In this case, near scale invariance is a generic feature of the theory if the field rolls in a steep self interaction potential.

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D. J. Mulryne, N. J. Nunes. 2006-10-10. Constraints on a scale invariant power spectrum from superinflation in LQC. https://doi.org/10.1103/physrevd.74.083507

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