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Could a rotating black hole experience Magnus type forces in the vicinity of a super-massive black-hole (non-rotating)? If it were falling towards the super-massive black-hole would it begin to revolve as well?

I must admit this question is simply out of curiosity. I was studying simple potential flows over a rotating cylinder and wanted to know if the same intuition held any significance in the context of rotating black holes.

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I would lean to yes, with the following reasoning: I look at it that way: The massive (non-rotating) black hole is free falling towards the rotating black hole. Bodys falling towards a rotating black hole expirence the Lense-Thirring-/Frame-Dragging-Effect so their geodesics get curved $d\phi/dt\ne 0$. This should be in principle independent of the mass of the free falling object, according to the equivalence principle.

This effect may look similar to the Magnus effect but has a totally different origin: the off diagonal Term of the Kerr metric is the reason for the Frame-Dragging-Effect.

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  • $\begingroup$ Thank you for the response. I would like to learn how I can calculate these effects. I lack any and all fundamentals to do so .. however am willing to learn. Please share any thoughts you might have in this regard. Thank you for your time, $\endgroup$ – SandeepRM Sep 1 '16 at 3:37
  • $\begingroup$ I am no expert on those dynamical problems in GR but you could research: "Lense-Thirring-/Frame-Dragging-Effect" or "Geodesics of Kerr metric". Calculating the dynamics of two BH falling towards each other looks not so easy to me because maybe one would need to account for both their grav. fields. So I can not show you a calculation for my answer; it is more an intuition, educated guess. If you would look at lets say a particle or space ship falling towards a rotating black hole/ compact body my answer will hold and calculating that should be easier because you only need to look at one field. $\endgroup$ – N0va Sep 22 '16 at 9:46

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