# Cyclic cosmology in modified gravity

## TL;DR

This paper introduces a new cyclic universe model based on modified gravity with higher order curvature terms, avoiding extra ingredients, and analyzes its phases through analytical and numerical solutions.

## Contribution

It proposes a novel cyclic cosmology model using curvature corrections in gravity without extra dimensions or exotic matter.

## Key findings

- Analytical solutions for each cycle phase.
- Numerical confirmation of the model's behavior.
- Detailed analysis of bounce and contraction phases.

## Abstract

In this work we propose a new general model of 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 therewith 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 ($\Lambda$CDM) phase, destruction of bounded systems and contracting phase - are analysed in detail. Focusing on some simple special cases, we obtain analytical and numerical solutions for the each phase confirming our analysis.