Mass and angular momentum of black holes: an overlooked effect of general relativity applied to the galactic center black hole Sgr A*

  title={Mass and angular momentum of black holes: an overlooked effect of general relativity applied to the galactic center black hole Sgr A*},
  author={Bernd R. Aschenbach},
  journal={Chinese Journal of Astronomy and Astrophysics},
  • B. Aschenbach
  • Published 8 March 2006
  • Physics
  • Chinese Journal of Astronomy and Astrophysics
I report the discovery of a new effect of General Relativity which is important to understand very rapidly rotating(Kerr) black holes. The orbital velocity of a test particle is no longer a monotonic function of the orbit radius when the spin of the black hole is >0.9953, but displays a local minimum-maximum structure for radii smaller than 1.8 gravitational radii. There the rate of change of the orbital velocity per radius unit equals the radial epicyclic frequency and is exactly one third of… 

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