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Inflationary scalar spectrum in loop quantum cosmology

Gianluca Calcagni·Marina Cortes
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Abstract

In the context of loop quantum cosmology, we consider an inflationary era driven by a canonical scalar field and occurring in the semiclassical regime, where spacetime is a continuum but quantum gravitational effects are important. The spectral amplitude and index of scalar perturbations on an unperturbed de Sitter background are computed at lowest order in the slow-roll parameters. The scalar spectrum can be blue-tilted and far from scale invariance, and tuning of the quantization ambiguities is necessary for agreement with observations. The results are extended to a generalized quantization scheme including those proposed in the literature. Quantization of the matter field at sub-horizon scales can provide a consistency check of such schemes.

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Gianluca Calcagni, Marina Cortes. 2007-01-18. Inflationary scalar spectrum in loop quantum cosmology. https://doi.org/10.1088/0264-9381%2F24%2F4%2F005

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