Integrable cosmological models with an additional scalar field

We consider modified gravity cosmological models that can be transformed into two-field chiral cosmological models by the conformal metric transformation. For the R-2 gravity model with an additional scalar field and the corresponding two-field model with the cosmological constant and nonstandard kinetic part of the action, the general solutions have been obtained in the spatially flat FLRW metric. We analyze the correspondence of the cosmic time solutions obtained and different possible evolutions of theHubble parameters in the Einstein and Jordan frames.

Automated summary

The study explores modified gravity cosmological models that can be transformed into two-field chiral cosmological models through conformal metric transformation. General solutions have been obtained in the spatially flat FLRW metric for the R-2 gravity model with an additional scalar field and the corresponding two-field model with nonstandard kinetic part of the action and a cosmological constant. The analysis focuses on the correspondence of cosmic time solutions obtained and the possible evolutions of Hubble parameters in the Einstein and Jordan frames.