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Where does it all go?

  1. Nov 4, 2005 #1
    You know, I'm probably not smart enough to be in here, but I have a burning question. I've often thought aboout this but I have never looked for an answer until now.

    Please correct me if I'm wrong. Blackholes are theories...right? Theories are truths that haven't been disproven. So...if blackholes are the vacuums of the entire entirety, where does all teh stuff go? I've read that possibly there may be light holes...exactly the opposite of the black holes. Is this a theory or a belief??

    Can anyone break it down in laymen terms??:smile:
  2. jcsd
  3. Nov 4, 2005 #2
    This is a place for asking questions, so its all good.

    In the strictest sense, no. Black holes are a consequence of a theory, not a theory in their own right. That said, the theory on which they're based has proven spectacularly right in every major experiment designed to test it.

    Its more complicated than that. A theory is an explanation of phenomenon that makes further predictions that can be tested and either verified or falsified. For examples. "God created the universe". That is a theory. Its an explanation of a phenomenon (existence). But its not a good scientific theory because its not testable, not falsifiable.

    That depends on specific conditions involved. If the matter falls into a nonrotating black hole, which has a point singularity it will be crushed into the singularity. If it falls into a rotating black hole, which has a ring singularity...well it gets more complicated, and General Relativity is not my field per se, so I couldn't say.

    Again, its a consequence of a theory. The idea is called an Einstein-Rosen bridge, a space time tunnel connecting a black hole and a white hole. However, in order to maintain this tunnel, the wormhole, some very bizarre things are required to happen (matter with negative density and such IIRC) that make it very unlikely to occur in nature, at least based on our experience of nature.
  4. Nov 5, 2005 #3
    Thanks for the help. I love reading in here.
  5. Nov 6, 2005 #4


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    I heard that the Hubble scope has observed BHs, banishing any lingering doubts about their existence.
  6. Nov 7, 2005 #5
    I don't know about Hubble, but we've had X-ray data on binary systems like cygnus X-1 for decades that strongly indicates they exist. There is no real debate on whether they exist, the only debate is in the details of their nature, none of which is clear because both GR and QM predict some very strange things that we don't entirely know how to interpret.
  7. Nov 7, 2005 #6


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    If you remember, I'd be curious to know the context of this. My impression is that very few astro and physics professionals doubt the existence of black holes, but short of one passing through the solar system, it would be near impossible to obtain proof of their existence. Most of the arguments so far (that I know of) are indirect:

    1) We infer masses by measuring the velocities of objects in the vicinity of the suspected black hole. If we measure a large mass in a small space, such that no other known object can be the culprit, we argue that it must be a black hole.
    2) In the case of massive stars, we argue that no known physical mechanism can support them above a certain mass threshold (once nuclear fuel is exhausted). Thus, compact objects with masses measured to be above ~3 solar masses are assumed to be black holes.
    3) We can argue that the energetics of system (such as the hardness of the spectrum or total luminosity) are too extreme to be generated by any other object. This is sometimes done for quasars.

    None of this involves direct detection of an event horizon. A detection of Hawking radiation would be much stronger support, but unfortunately, such radiation is extremely weak for all but the smallest black holes.
  8. Nov 8, 2005 #7
    It's more than likely that Black holes are huge old dead Stars that had enormous Neutron cores that collapsed into a singularity, some had fast spins and some had slow spins.

    There should be lots of old dead stars floating around the Universe black as can be..
  9. Nov 8, 2005 #8


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    advances another indirect argument for the existence of event horizons.

  10. Nov 8, 2005 #9
    Hey, How about Top Quark Core Stars, Neutron Singularities collapsed into a Top Quark core? Would there be enough energy in the event for Top Quarks to be present even for a few moments between production of Top Quarks in the reaction of the singularity?
  11. Nov 8, 2005 #10


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  12. Nov 8, 2005 #11


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    I'd never even heard of quark stars until the thread about singularities popped up. Fascinating. Thanks for the link.
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