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

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.