Curvature Induced Acceleration and Reheating of the Universe

Abstract

We present some solutions in a modified theory of gravity with R 2 and 1 R terms in the Einstein-Hilbert action with an ideal fluid in FLRW spacetime. Graceful exit from early inflation to radiation dominated era is obtained in the strong curvature regime preceding a fluctuation of effective equation of state parameter at the end of inflation. In the weak curvature regime the universe evolves through a radiation era that subsequently turns to a matter era and finally transits to late time accelerating era.