MG13 - Talk detail

Back to previous page

 Participant

Institution

Session

Accepted

Order

Time

Talk

Title

Abstract

We consider super-inflating solutions in modified gravity for several popular $f(R) $ functions.Using non-standart way of scalar field reformulation in $f(R)$-gravity we describe how the form of effective scalar field potential can be used for explaining existence of stable super-inflation solutions in the theory under consideration.It was shown that the presence of the global minimum of the effective potential appears to be incompatible with super-inflating cosmological solutions, on the other hand,unboundedness of the potential from below indicates existence of such solutions.As an application of this property we considered three families of functions $f(R)$ very popular in current researches on modified gravity, namely $R+\alpha R^N$, $R+\alpha R^N \exp{R}$ and $R+\alpha R^N \ln{R}$.Several super-inflating solutions for these families have been found analytically and checked numerically. It appears that only the following potentials from these infinite families are free from stable super-inflation: the known $R+\alpha R^N\, (1<N<2)$; $R+\alpha R^2 (\alpha>0)$ cases and the case of $R+\alpha R^{N}\ln{R}\,(1\leq N<2)$. All other $f(R)$ functions from these families contain stable super-inflating solutions, some of them have not been discovered earlier.

Back to previous page