A nonlocal gravity model which does not assume the existence of a new dimensional parameter in the action and includes a function f(□-1 R), with □ the d'Alembertian operator, is studied. By specifying an exponential form for the function f and including a matter sector with a constant equation of state parameter, all available power-law solutions in the Jordan frame are obtained. New power-law solutions in the Einstein frame are also probed. Furthermore, the relationship between power-law solutions in both frames, established through conformal transformation, is substantially clarified. The correspondence between power-law solutions in these two frames is proven to be a very useful tool in order to obtain new solutions in the Einstein frame. © 2013 IOP Publishing Ltd and Sissa Medialab srl.
- Dark energy theory
- Modified gravity