We discuss the existence of inflationary solutions in a class of renormalization group improved polynomial f(R) theories, which have been studied recently in the context of the asymptotic safety scenario for quantum gravity. These theories seem to possess a nontrivial ultraviolet fixed point, where the dimensionful couplings scale according to their canonical dimensionality. Assuming that the cutoff is proportional to the Hubble parameter, we obtain modified Friedmann equations which admit both power-law and exponential solutions. We establish that for sufficiently high-order polynomial the solutions are reliable in the sense that considering still higher-order polynomials is very unlikely to change the solution.
|Titolo:||Inflationary solutions in asymptotically safe f(R) theories|
|Autori:||Bonanno A; Contillo A; Percacci R|
|Rivista:||CLASSICAL AND QUANTUM GRAVITY|
|Data di pubblicazione:||2011|
|Digital Object Identifier (DOI):||10.1088/0264-9381/28/14/145026|
|Appare nelle tipologie:||1.1 Journal article|