Modified gravity as an alternative for Lambda-CDM cosmology

Abstract

The reconstruction scheme is developed for modified $f(R)$ gravity with realistic matter (dark matter, baryons, radiation). Two versions of such theory are constructed: the first one describes the sequence of radiation and matter domination, decceleration-acceleration transition and acceleration era and the second one is reconstructed from exact Lambda-CDM cosmology. The asymptotic behaviour of first model at late times coincides with the theory containing positive and negative powers of curvature while second model approaches to General Relativity without singularity at zero curvature.