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arXiv · 2501.01948

A New Approach to the Analysis of Cosmological Parameters in Multifield Cosmology

Katerina Bolshakova·Sergey Chervon
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Abstract

Currently, a method has been developed for the cosmological inflation model with a single scalar field to calculate cosmological parameters such as the power spectrum of scalar and tensor perturbations, their spectral indices, and the tensor-to-scalar ratio. However, for a multifield configuration, a definitive method for calculating cosmological parameters has not yet been established. We propose a new effective algorithm for determining cosmological parameters within the tensor-multi-scalar theory of gravity, which describes the early inflationary epoch of the Universe. Our approach is based on utilizing a specific analytical solution within a multifield cosmological model to establish functional relationships between fields. This method enables the computation of cosmological parameters and their comparison with observational data.

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Katerina Bolshakova, Sergey Chervon. 2025-01-03. A New Approach to the Analysis of Cosmological Parameters in Multifield Cosmology. https://arxiv.org/abs/2501.01948

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