1/R gravity and scalar-tensor gravity

  title={1/R gravity and scalar-tensor gravity},
  author={Takeshi Chiba},
  journal={Physics Letters B},
  • T. Chiba
  • Published 18 July 2003
  • Physics
  • Physics Letters B
Abstract We point out that extended gravity theories, the Lagrangian of which is an arbitrary function of scalar curvature R , are equivalent to a class of the scalar-tensor theories of gravity. The corresponding gravity theory is ω =0 Brans–Dicke gravity with a potential for the Brans–Dicke scalar field, which is not compatible with solar system experiments if the field is very light: the case when such modifications become important recently. 
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