Tests of Gravity Theories Using Supermassive Black Holes

@article{Sakstein2017TestsOG,
  title={Tests of Gravity Theories Using Supermassive Black Holes},
  author={Jeremy Sakstein and B. Jain and Jeremy S. Heyl and Lam Hui},
  journal={The Astrophysical Journal Letters},
  year={2017},
  volume={844}
}
Scalar-tensor theories of gravity generally violate the strong equivalence principle, namely that compact objects have a suppressed coupling to the scalar force, which causes them to fall slower. A black hole is the extreme example where such a coupling vanishes, i.e., black holes have no scalar hair. We explore observational scenarios for detecting strong equivalence principle violation, focusing on galileon gravity as an example. For galaxies infalling toward galaxy clusters, the supermassive… 

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