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From every angle, what is the complete shape of a black hole?

  1. Aug 18, 2011 #1
    Is it shaped like a tornado, or a sphere, or is it flat like a disk? If there was a way to view a black hole, dimming the brightness around it to get a clear look, what would be its full shape if you could view all around the outside of it from every possible angle?
  2. jcsd
  3. Aug 18, 2011 #2
    This is an interesting question. From outside it would resemble a black 3d sphere rather than a "hole". However most black holes are actually bright at a distance due to the matter which consists of the accretion disk.

    This is my current understanding but I am sure you will get some more feedback from more knowledgeable PF members.
  4. Aug 18, 2011 #3


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    Black holes have a spherical event horizon however they can be surrounded by accretion discs or in the case of rotating black holes you can get an http://en.wikipedia.org/wiki/Rotating_black_hole" [Broken].
    Last edited by a moderator: May 5, 2017
  5. Aug 18, 2011 #4
    Rotating Universes are also the theoretical environments required for naked singularities. Which is very interesting - although these have never been observed and are theoretical only.

    I think black holes would appear to the observer as 2D circular void - it would not have any dimension other than 2D from FoR of the observer? It would just look like a completely black "hole" and if you could move around it at relatavistic speeds in any direction (outside of the EH) it would look as if the "hole" were rotating with you. This is assuming the BH has no large accretion discs, can anyone advise if the disc is a disc in the traditional sense or a
    3D envelopment?

    I just imagine a void, with total information exchange breakdown - almost like a pre-universe void; like the opposite of the Big Bang... Maybe too many sci fi books!
    Last edited by a moderator: May 5, 2017
  6. Aug 18, 2011 #5


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    Or http://en.wikipedia.org/wiki/Ring_singularity" [Broken] which are equally as interesting.

    Indeed though you may still perceive it to be a sphere by virtue of orbiting it and always seeing a circle.

    http://en.wikipedia.org/wiki/Accretion_disc" [Broken] are 3d but they are disc shaped.
    Last edited by a moderator: May 5, 2017
  7. Aug 18, 2011 #6
    Thank you everyone. Do we know enough about the physics of a black hole to accurately model it on a computer? If so, I would think the software would allow a user to rotate around it from all angles to see its full shape.
  8. Aug 18, 2011 #7
    Probably is such sofftware but as black holes should contain a singularity by their very nature and a singularity is mathematical nonsense and not considered a real singularity (an object with zero volume and infinite mass) but a point where current mathematics theory breaks down and general relativity no longer holds true - this is where a theory of quantum gravity is required.

    Their shape is pretty much as described - a 2D looking spherical hole in 3d space that looks the same from all dimensions - unless surrounded by an accretian disc.
  9. Aug 19, 2011 #8
    I would figure a sphere but slightly streched at the equatord due to the spin and all the other matter around the disc
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