K.A. Bolshakova1, S.V. Chervon2

1, 2 Ulyanovsk State Pedagogical University (Ulyanovsk, Russia)
2 Bauman Moscow State Technical University (Moscow, Russia)
2 Kazan Federal University (Kazan, Russia)
1 bolshakova.ktrn@gmail.com, 2 chervon.sergey@gmail.com

Currently, for the cosmological inflation model with one scalar field, a method has been developed for calculating cosmological parameters, such as the power spectrum of scalar and tensor perturbations, their spectral parameters, and the tensor-to-scalar ratio. In the case of a multifield configuration, an suitable method for calculating cosmological parameters has not been developed. We propose a new effective algorithm for finding cosmological parameters in the tensor-multi-scalar theory of gravity (TMS TG), which describes the era of early inflation of the Universe. The paper proposes a new approach based on the use of a special case of an analytical solution in a multifield cosmological model to establish a functional connection between fields. This method makes it possible to calculate cosmological parameters and their comparison with observational data.

Bolshakova K.A., Chervon S.V. A new approach to the analysis of cosmological parameters in multifield cosmology. Nonlinear World. 2024. V. 22. № 3. P. 91–103. DOI: https://doi.org/10.18127/ j20700970-202403-09 (In Russian)

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