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Super-black holes and the universe

  1. Dec 9, 2005 #1
    I was trying to fall asleep last night and began to ponder about the universe. This isn't something unusual, it helps me sleep. But I came across a thought that stood out from the previous ones that I simply discarded.

    Shortly after reading a few chapters of "A brief history of time" I became focused on black holes. And I previously read a few articles on super-black holes....the ones found at the center of a galaxy.

    Anyways, I began to ponder, what if all the matter being taken-into a black hole is merely being pushed out the "other end". What if a duplicate universe exists on the other side of a black hole, one that expulses the matter taken from our universe, into another. This could explain why our galaxy revolves around such a mass, and where it goes.....

    Just a thought, was wondering if you can support/discard this theory?

    Seems to follow most of the previous theories....other than the ever-expanding universe.....which could still fall into the bigger picture though.
  2. jcsd
  3. Dec 9, 2005 #2


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    There do exist black hole solutions in which black holes can behave as a "bridge" to other universes, but each has its problems.

    For example, a non-rotating, uncharged black hole (Schwarzschild solution) can theoretically exist such that there are four regions of spacetime -- two asymptotically flat, one black hole, and one white hole. One of the asymptotically flat regions is where we live and the other could be a hypothetical "alternate universe". Unfortunately, in this picture, the two asymptotically flat regions cannot communicate with one another. The only place we could meet folks from this alternate universe would be inside the black hole itself. Since any observer that falls into a black hole is doomed to fall into the singularity in a finite time, we'd probably be better off not meeting.

    Another problem with the above picture is that it requires special initial conditions. The alternate universe is not created when a black hole is created, the whole structure must have already existed beforehand. The supermassive black holes in your question do not actually correspond to this full Schwarzschild solution -- they just have one asymptotically flat region (our universe) and a black hole.

    The Schwarzschild solution is not the only one that provides a possible connection to another universe. For example, there are hypothetical "wormhole" solutions for which you don't need to fall into a singularity to meet with folks from the other universe. The debate about the plausibility of wormholes is ongoing, but GR certainly provides a lot of room for playful speculation.
    Last edited: Dec 10, 2005
  4. Oct 7, 2010 #3
    Hey, love pondering btw :) I think there could be alternate universes with white holes because if all the matter is crushed into a singularity, why doesn't the gravity of the black hole increase?? another thing is that the amount of energy (in one form or another)throughout our universe is constant and if matter from this universe were to be emitted into another, energy from this universe would be lost. Has there been any evidence supporting this?? thanks :) by the one, how do you post threads? i'm new and don't know =/
  5. Oct 7, 2010 #4


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    No evidence exists suggesting energy is being 'lost' from this universe. This would, among other things, violate the first law of thermodynamics [energy conservancy].
  6. Oct 8, 2010 #5
    This statement is ALMOST true. As we all know, energy can't be created or destroyed, this is called conservation of energy. One of lights most important features is that it gets red-shifted (It's electro-waves get stretched) in accordance with Einstein's theory of relativity, so the longer the wavelength, the lower the energy. When the light is red-shifted it gets you pondering... Where does this Energy go? Is it violating one of our most important theories?

    I am not a big fan of the word "Theory" as it is a poor and simplified Creationist Construct, so believe what you will.

    There is no shortage of "Theories" but we dont even know where Dark Energy comes from.. What it's even made of or consists of. Where is this Energy being poured from?

    I'd have to go into specifics, and scientific data which it's too early to do, but the OP's (Original Poster) comments are worth divulging.
  7. Oct 8, 2010 #6
    "I am not a big fan of the word "Theory" as it is a poor and simplified Creationist Construct, so believe what you will. "

    I think the science community might find a problem with that, as a 'theory' in science carries a great deal of weight, its not a pypothesis, or a speculation.

    The creationist debate (if you can call it that) was about the theory of natural selection being 'only' a theory, and not a 'fact'.
    But it was proved in court that allthough theories can be disproved there are many theories that are backed up by vast amounts of practical evidence, and until something better is proposed it as good as a fact.

    I guess a law (like Ohms law) is stronger than a theory, but I still think theories carries a great deal of weight in science.
  8. Oct 8, 2010 #7
    Im not saying a Theory does not carry weight, because it does, or we would have nothing - but all it is, is a theory.

    The theory the Earth is Flat.

    The fact Earth is Round.

    So a theory IS a theory until it becomes a fact... Until then, it IS speculation with weight.
  9. Oct 8, 2010 #8


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    Red shifted photons are also time dilated, so any energy 'loss' is less than obvious. You must resort to GR to flesh out the nuances, and I believe GR satisfactorily accounts for any 'missing' energy.
  10. Oct 8, 2010 #9
    People have already thought of this, google for Leo Smolin and fecund universes and cosmological natural selection. The idea is that universes that can produce stars that produce black holes will create new universes and so ultimately you end up with more universes.

    Smolin argues that his idea is refutable. Other people disagree. The big problem is that since we don't have a good theory of quantum gravity, you can make up anything.
  11. Oct 8, 2010 #10
    There is no reason that it should. If you change the density, gravity doesn't increase.

    There's no reason to think that energy is being lost from our universe. However, mixing energy and general relativity can get you some weird things.
  12. Oct 8, 2010 #11
    Depends. I have a Ph.D. in astrophysics, and I strongly dislike the term "theory." I much prefer "model." All models are wrong. Some models are useful.
  13. Oct 8, 2010 #12
    like i said... im new and dont know how to start threads :( please help
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