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arXiv · 2006.03092

Generation of inflationary perturbations in the continuous spontaneous localization model: The second order power spectrum

Gabriel Leon·Maria Pia Piccirilli
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Abstract

Cosmic inflation, which describes an accelerated expansion of the early Universe, yields the most successful predictions regarding temperature anisotropies in the cosmic microwave background (CMB). Nevertheless, the precise origin of the primordial perturbations and their quantum-to-classical transition is still an open issue. The continuous spontaneous localization model (CSL), in the cosmological context, might be used to provide a solution to the mentioned puzzles by considering an objective reduction of the inflaton wave function. In this work, we calculate the primordial power spectrum at the next leading order in the Hubble flow functions that results from applying the CSL model to slow roll inflation within the semiclassical gravity framework. We employ the method known as uniform approximation along with a second order expansion in the Hubble flow functions. We analyze some features in the CMB temperature and primordial power spectra that could help to distinguish between the standard prediction and our approach.

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Gabriel Leon, Maria Pia Piccirilli. 2020-08-12. Generation of inflationary perturbations in the continuous spontaneous localization model: The second order power spectrum. https://doi.org/10.1103/physrevd.102.043515

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