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How can a black hole attract nothing at all?

  1. Dec 26, 2003 #1
    If we accept gravity force is driven by particle interchange (graviton), then in a black hole it wouldn't be posible for them to escape its event horizon. So, the black hole's gravity would be confined in itself because the gravitation particles can not surpase the light speed limit.

    So, what's wrong?

    1) The interchange of gravitons.
    2) The light speed limit.
    3) The black hole singularity.
    4) All of the above.
    5) All that I think I know in physics...:wink:
  2. jcsd
  3. Dec 26, 2003 #2
    Last edited: Dec 26, 2003
  4. Dec 26, 2003 #3
    Hi Jimmy.

    I just read the link you posted. It seems to me the same old thing. When something doesn't work in the theory a new particle appears with new amazing powers. I tend to think the simplest answer is the correct one and there have been already too many patches to the SR and GR.

    In this link www.autodynamics.org is proposed a diferent point of view that seems to me much more coherent and simple than "virtual" particles.

    Best regards :smile:
  5. Dec 26, 2003 #4
    If you wanted to plug your favorite pet theory, why didn't you just do that instead of pretending you wanted to learn something, then including your theory in a "clever" reply?
  6. Dec 26, 2003 #5


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    Black holes are funny that way. Gravity is still present because of the effect on time of the black hole. Specifically, to an outside observer, black holes never actually form - time near a black hole appears to slow down. Something falling in will appear never to get there, but will just get redder nearing the surface. What all this means in terms of gravitons is that the black hole to be is exerting gravity like any other massive object.
  7. Dec 26, 2003 #6
    Your theory that the black hole's gravity would be confined in itself is what's wrong. Asking "how can a black hole attract nothing?" is like asking "how can humans not exist?", or "How can hydrogen be composed of oxygen?".
  8. Dec 26, 2003 #7


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  9. Dec 27, 2003 #8
    Just my thoughts:
    For gravity to be characterized(not by anyone here) as an "emissive" force, like a photon or other nucleonic interchange "particles", seems somewhat absurd to me. In my opinion, the notion of a graviton falls into the same category as the notion of a magnetic monopole.
    The total understanding of gravity surely is the holy grail of physics.

    Perhaps there are those who could add to or correct the following:

    - Gravity is an event, not a process per se.
    - Gravity is a characteristic of mass(the great unknown)
    - An individual particle without charge has no mass.
    - The apparent relationship between particle charge and mass tickles the mind into unification theory.
    - True anti-gravity(a repulsive force to standard gravity)has never been observed in nature.
    - Acceleration of a charged particle or any atom or atomic system increases mass.
  10. Dec 29, 2003 #9
    I'm sorry if I disturb you, but sometimes when someone makes a question doesn't necesarily mean he needs to "learn", but to contrast reasoned ideas in a open minded way.

    I think a forum is a place to relativize ideas. To "believe" in the standard theory I only need a book and some amount of faith, but new ideas are not in the "official" books and I want to know other reasoned posibilities. :wink:
  11. Dec 29, 2003 #10
    But what does it happen with the mass inside the black hole?. There's much more mass inside the black hole than outside so, following your reasonament, as the black hole collapses the part of mass that contributes to gravity is the ever falling mass which couldn't posibly be able to create the same attraction effect than inner mass (because of being much smaller in mass).

    So, the relativistic effect decreases and the time speeds up again.
  12. Dec 29, 2003 #11
    Re: Re: How can a black hole attract nothing at all?

    Well, I think is not quite the same.

    Black holes will remain black althoug they don't attract nothing at all because the light doesn't escape from its gravitatory field.

    The black hole will still collapse but, in the moment that its event horizont appears, its outside gravitatory effect will cease.
  13. Dec 29, 2003 #12
    Outside gravity effect won't cease. A black hole can be visualized like a hole in the ground that has gradually steeper sides. Vehicles, like SUVs explore down the ever-increasing slope, but at some point they fall into the hole and can't get back out. The mass that caused the gentle slope also causes the steep slope.

    After reading these posts, I realized a black hole is most unique because it can lose mass and still have the same gravitational attraction. We have a situation in the center of our galaxy where black holes stop feeding, then start feeding again. Where is the mass going?
  14. Jan 2, 2004 #13
    The anwser is quite simple. Once all matter and energy within the event horizon have been consumed by the black hole, the force of gravity becomes so great that all of it's mass and energy are squeezed to the point where all of it's matter are balsted out the poles (simmilar to a wet bar of soap that is squeezed).
  15. Jan 4, 2004 #14
    Happy new year :smile:.

    I've been reading some articles about the topic that lead to new questions.

    If the particles carring the gravitational force travel faster than light but at finite speed (including the virtual particles), then the black hole will have a longer gravitational life. It becomes black and increases its gravity until it's so strong that the gravitational particles can't escape. Again, the black holes's gravitational force dissapears.

    This situation creates new problems. The relativistic effects will change because we've got particles traveling faster than light (virtual particles).

    Furthermore, what is more interesting to me, if the gravitational particles are finally self-confined, what happens if they interact with the mass that emitted them but in the opposite way? (It would be as if all the internal mass emitted particles, and half-way through they turned around and hit the mass again).

    And, could the back hole become inestable and explode?

    In my opinion, this would be a very interesting recycle system for cosmic matter.
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