f(R) Theories

  title={f(R) Theories},
  author={Antonio De Felice and Shinji Tsujikawa},
  journal={Living Reviews in Relativity},
Over the past decade, f(R) theories have been extensively studied as one of the simplest modifications to General Relativity. In this article we review various applications of f(R) theories to cosmology and gravity — such as inflation, dark energy, local gravity constraints, cosmological perturbations, and spherically symmetric solutions in weak and strong gravitational backgrounds. We present a number of ways to distinguish those theories from General Relativity observationally and… 
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