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arXiv · 1301.1264

Duration of inflation and conditions at the bounce as a prediction of effective isotropic loop quantum cosmolog

Linda Linsefors·Aurelien Barrau
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Abstract

Loop quantum cosmology with a scalar field is known to be closely linked with an inflationary phase. In this article, we study probabilistic predictions for the duration of slow-roll inflation, by assuming a minimalist massive scalar field as the main content of the universe. The phase of the field in its "prebounce" oscillatory state is taken as a natural random parameter. We find that the probability for a given number of inflationary e-folds is quite sharply peaked around 145, which is consistent with the most favored minimum values. In this precise sense, a satisfactory inflation is therefore a clear prediction of loop gravity. In addition, we derive an original and stringent upper limit on the Barbero-Immirzi parameter. The general picture of inflation, superinflation, deflation, and superdeflation is also much clarified in the framework of bouncing cosmologies.

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Linda Linsefors, Aurelien Barrau. 2013-06-03. Duration of inflation and conditions at the bounce as a prediction of effective isotropic loop quantum cosmolog. https://doi.org/10.1103/physrevd.87.123509

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