Cyclic cosmology in modified gravity

In this work we propose a new general model of the eternal cyclic Universe. We start from the assumption that quantum gravity corrections can be effectively accounted by the addition of higher order curvature terms in the Lagrangian density for gravity. It is also taken into account that coefficients associated with these curvature corrections will in general be dependent on a curvature regime. We therefore assume no new ingredients, such as extra dimensions, new scalar fields, phantom energy or special space-time geometries. Evolution of the Universe in this framework is studied and general properties of each phase of the cycle---cosmological bounce, low curvature ($\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$) phase, destruction of bounded systems and contracting phase---are analyzed in detail. Focusing on some simple special cases, we obtain analytical and numerical solutions for each phase confirming our analysis.

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