ENERGY CONDITIONS IN f(R) GRAVITY AND BRANS–DICKE THEORIES

Abstract

The equivalence between f (R) gravity and scalar-tensor theories is invoked to study the null, strong, weak and dominant energy conditions in Brans-Dicke theory. We consider the validity of the energy conditions in Brans-Dicke theory by invoking the energy conditions derived from a generic f (R) theory. The parameters involved are shown to be consistent with an accelerated expanding universe.

More on modified Gauss-Bonnet gravity

“…Phantom field potential (Santos and Alcaniz 2005), expansion history of the universe (Visser 1997a(Visser , 1997bSantos et al 2006Santos et al , 2007aSen andScherrer 2008, 2007b) and evolution of the deceleration parameter (Gong et al 2007;Gong and Wang 2007) have been investigated using classical energy conditions of general relativity. Energy conditions in the context of f (R) gravity have been derived in Santos et al (2007c) and following the formalism developed in Santos et al (2007c), several authors have studied some cosmological issues in modified f (R) gravity from this point of view (see for example Santos et al 2010;Atazadeh et al 2009). Also, appropriate energy conditions for the f (R) gravity non-minimally coupled with matter Lagrangian has been investigated in Bertolami and Sequeira (2009).…”

Energy conditions in modified f(G) gravity

“…Some of the literature review of ECs were discussed by using the classical ECs of general relativity (GR) like the phantom fields potential [46], the history of expanding universe [47][48][49][50][51][52] and the pattern movement of deceleration parameters [53,54]. The various expression for ECs are derived in f (R) gravity [55] and using these formalism and techniques, some authors have pointed out some issues (cosmological) in f (R) gravity [56][57][58]. The general formalism for ECs are derived in f (G) gravity by García et al [59].…”

Energy conditions in $$f(\mathcal {G},T)$$ f ( G , T ) gravity

“…The energy conditions have been investigated in different modified theories of gravity like f (R) gravity, BransDicke theory, f (G) gravity, and generalized teleparallel theory [22][23][24][25]. Banijamali et al [26] investigated the energy conditions for non-minimally coupling f (G) theory with L m and found that the WEC is satisfied for specific viable f (G) models.…”