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Black Hole Question

  1. May 23, 2014 #1
    I am no cosmologist, just purely curious as to what the explanations and if there are explanations currently to some of my questions:

    If it was possible can one fly far enough around a blackhole in all 360 degree angles, i assume yes one could but what the question leads to is, does it have a north and a south pole, if matter moved towards it from the top would it automatically
    be forced to the side to form part of the disc of debris. So behaving like a planet such as saturn or any planet with rings.

    Could the BH have a surface like a planet or could it perhaps have punched through the fabric of space letting the matter out into some other space or dimension, but no white holes have ever been discovered ?

    Another question would be if it does not punch through the fabric of space, where does all the matter get piled up, or does everything in it convert to pure energy and somehow escapes into the universe.
  2. jcsd
  3. May 23, 2014 #2


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    1) I don't quite understand your question about flying around all 360 degree angles of a black hole. We live in 3-dimensions, not two, so...are you saying does the universe exist in all directions? ... in what possible scenario could we not go around an object?

    2) A black hole may be rotating or non-rotating. A rotating black hole will indeed tend to form discs of accretion around it, and perhaps emitting jets of x-ray or gamma radiation.

    3) "Punching a hole through the fabric of space-time" is a very ill defined concept. Spacetime, although sometimes likened to a fabric, is NOT a fabric, and so "punching a hole in it" doesn't quite make sense. Now, the singularity itself (at the very center, r=0), by virtue of it being a singularity is indeed conventionally absent from the manifold, but the interior of a black hole not at the single point (line I guess if you view this in 4 dimensions) of the singularity is well defined.

    The matter, as far as we know, just stays inside the black hole. "Piled up" as you say in the singularity. Matter escaping from a black hole can only occur via Hawking radiation, and this is an extremely slow process for astronomical black holes.
  4. May 23, 2014 #3


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    It is possible to fly around a black hole. Just stay far enough away from the black hole so that: 1.) you don't fall into the event horizon, and 2.) you don't get ripped apart by tidal forces.

    Whether a black hole has "poles" or not depends on if it has a magnetic field or not. However, even then, matter could still fall into it from any direction, as the accretion disk can form in any plane around the black hole. Of course, if there is already an accretion disk then infalling matter would tend to collide with this accretion disk and be swept up into its plane over time.

    No. The event horizon is not a physical surface, it is simply the point where space becomes so curved that no paths through spacetime lead away from the black hole. What lies beyond this is unknown, but it is most definitely not a surface like a planet. Gravitational forces are too high to allow matter to keep its normal form. If we assume that there isn't really a singularity then you'd probably be looking at a very dense compact object made up of subatomic particles bound together in exotic forms. Something like a quark star perhaps.

    It definitely doesn't punch a "hole" in spacetime. Spacetime is not a fabric that can have holes punched in it.

    Over a very long time all the matter probably gets converted into radiation and emitted as hawking radiation until the black hole evaporates.
  5. May 23, 2014 #4


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    Google the "No-Hair Theorem"
  6. May 24, 2014 #5
    Thanks for the replies, i feel that most of my questions have been explained above thanks, just the one about space time and what goes on in the blackhole where we cannot see anything.

    Here's how i see it, you cannot punch a hole through the invisible air we breath on earth, however beyond our atmosphere is space, so i feel that beyond space there should possibly be something else, perhaps not space or time, we just have no way of detecting it at the moment, otherwise space/time goes on for infinity which is hard to believe at least for myself.

    As we can only see what we can see and detect what we currently can detect, i understand that there's probably no definite answer for this last question.

    Again thanks for the answers.

    If a blackhole completely evaporates over time, should there not be some remnant left like a quasar.
  7. May 24, 2014 #6


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    I mean no disrespect but the universe and the laws of physics absolutely do not care what you think or what you feel is reasonable. This "something other than space or time" concept is wildly unsupportable personal speculation of the sort that is not what this forum is about.

    Yes, space-time going on for infinity is a tough concept BUT ... so is the concept of it NOT going on for infinity.

    Black hole evaporation is like the water evaporating from a bowl. Why would you expect for there to be anything left?

    Before you decide that modern physics is nonsense, I suggest that you learn some more about it.
  8. May 24, 2014 #7
    i don't think it's nonsense thats why i post here, of course nature does not care what i think however thats just the problem, we as tiny spec humans on a tiny spec of dust does not know it all, anyway i will end this discussion here as i know it's starting to get a bit off topic according to the rules that be on this site.
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