Constant-roll inflationary models in Einstein — Gauss — Bonnet gravity

This work investigates constant-roll inflationary models based on modified Einstein–Gauss–Bonnet gravity. Special attention is paid to analyzing the influence of the Gauss–Bonnet topological invariant on the parameters of cosmological perturbations. A comparison of the obtained solutions with the case of Einstein gravity is performed, and characteristic features of the new models are identified. The consistency of the considered cosmological inflation models with observational constraints on the values of cosmological parameters is also verified. The results of this study can be applied in the interpretation of cosmic microwave background observations (Planck, BICEP), for refining the inflationary dynamics of the early Universe, and in theoretical studies of modified gravity theories.

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