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arXiv · 2309.15984

Analytic Approximations for the Primordial Power Spectrum with Israel Junction Conditions

D. D. Dineen·W. J. Handley
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Abstract

This work compares cosmological matching conditions used in approximating generic pre-inflationary phases of the universe. We show that the joining conditions for primordial scalar perturbations assumed by Contaldi et al. are inconsistent with the physically motivated Israel junction conditions, however; performing general relativistic matching with the aforementioned constraints results in unrealistic primordial power spectra. Eliminating the need for ambiguous matching, we look at an alternative semi-analytic model for producing the primordial power spectrum allowing for finite duration cosmological phase transitions.

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D. D. Dineen, W. J. Handley. 2023-09-27. Analytic Approximations for the Primordial Power Spectrum with Israel Junction Conditions. https://doi.org/10.1103/physrevd.109.083513

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