Energy conditions in f(R) gravity and Brans-Dicke theories
  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. 
K. Atazadeh, A. Khaleghi, H. R. Sepangi, Y. Tavakoli