Constraining f(G) Gravity Models Using Energy Conditions

Abstract

Recently, energy condition inequalities in the context of modified Gauss-Bonnet gravity have been derived in Garcia et al. (Phys. Rev. D, 83:104032, 2011). Using these general inequalities, we examine the viability of specific forms of f (G) models proposed in De Felice and Tsujikawa (Phys. Lett. B, 675:1, 2009) that can be responsible for the late-time cosmic acceleration following the matter era. In doing so we also use the recent estimated values of the deceleration, jerk and snap parameters to obtain the bounds from the weak and strong energy conditions on the parameters of the above mentioned forms of f (G) gravity theories.

Energy conditions in modified f(G) gravity

“…García et al [60] have explored some viable f (G) models and checked their viability epochs by exploring ECs. Sadeghi et al [61] have explored some f (G) garvity models that could obey WEC and SEC in an era where late-time de-Sitter solution was stable. Banijamali et al [62] analyzed the distribution of WEC for a class of consistent f (G) models and claimed that power law model of the type f (G) = ǫG n would satisfy WEC on setting ǫ < 0.…”

Phenomenological models of Universe with varying G and Λ

“…F (R T ) theory is an other powerful alternative model [36], but it violates the first law of thermodynamic [37]. Other example could be the (G GB ) [38][39][40][41][42] action that describes Einstein's gravity coupled with perfect fluid plus a Gauss-Bonnet (G GB ) term given as…”

The Solution of Electromagnetic Field in AdS² with Factrization Method

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