I.V. Fomin1

1 Bauman Moscow State Technical University (Moscow, Russia)
1 fomin_iv@bmstu.ru

Currently, a large number of models of the early universe based on Einstein gravity and its various modifications are being considered. To construct scenarios for the evolution of the early universe, as a rule, inflationary models with certain parameters which are compared with observational data are used. There is no unified method for classifying inflation models in the context of their verification in the literature..

This paper is devoted to the development of a new method for classifying cosmological inflation models in the context of their verification using observational restrictions on the values of cosmological perturbations parameters. Development of a method for parameterizing the influence of modified theories of gravity on the values of parameters of cosmological models and evaluation of these parameters for cosmological models verified by observational data.

A classification of cosmological models is proposed according to the order of expansion of the dependence of the tensor-scalar ratio on the spectral index of scalar perturbations. A method for verifying arbitrary models of cosmological inflation is proposed based on taking into account the non-minimal coupling between the scalar field and the Gauss-Bonnet scalar. The generalization of this approach to arbitrary modifications of Einstein gravity is discussed.

The proposed classification of cosmological inflationary models allows to consider the criterion of their compliance with observational constraints on the values of the parameters of cosmological perturbations, regardless of the type of modification of Einstein gravity. Also, the considered approach to parameterizing the influence of modified theories of gravity on the characteristics of cosmological perturbations and background parameters of inflationary models allows one to consider cosmological models with arbitrary background parameters as fundamentally verified by observational constraints.

Fomin I.V. Parameterization of the influence of modified gravity theories on the characteristics of cosmological perturbations. Nonlinear World. 2024. V. 22. № 3. P. 19–29. DOI: https://doi.org/10.18127/ j20700970-202403-03 (In Russian)

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