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Black hole gravity response question

  1. Jun 4, 2007 #1
    Can anybody tell me if there are any puzzles or anomalies with respect to candidate black holes? For example if we have a binary system that looks like this:

    o O

    where the o is a candidate black hole and the O is a star of some typical type and mass, one would observe each object orbiting the other. Does anybody know if there's have been any unusual observations or inferences?

    Thanks in advance.
  2. jcsd
  3. Jun 5, 2007 #2
    This is the sort of thing I meant. Can anybody advise or inform please?


    Abstract: The recently discovered anomalous orbital velocity effect, which implies a reduced velocity with decreasing radius for an orbiting test particle, is present in extreme Kerr black holes with spin > 0.9953 and radii between 1.05 and 1.78 gravitational radii. In this region a 3:1 resonance between the vertical and the radial epicyclic frequencies occurs, which may lead to quasi-peridoc light variations with two periods differing by a factor of 3. Such variations may have been observed from the Galactic Center black hole Sgr A*. At the same spin but at a larger radius a 3:2 resonance between the two epicyclic frequencies is found as well. Such 3:2 frequencies have been observed in four galactic microquasars. In either case, i.e. the 3:1 or the 3:2 resonance, the black hole mass determined from this model agrees very well with the dynamical mass for Sgr A* and each of the four microquasars. Meanwhile the microquasar GRS 1915+105 has been classified by its X-ray spectrum as an extreme Kerr black hole with a spin > 0.98 [1], which agrees quite nicely with our prediction for the spin, i.e. a = 0.996. Model and observational data are presented and discussed.

    I'll perhaps search a variety of papers then print and study.
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