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Black holes, white holes and expansion of Universe

  1. Dec 17, 2009 #1
    What I am posting here it is not an alternate theory nor a criticism of any accepted theory.
    I just have an idea born from what I know (like a non-specialist) about cosmology and I need your help to understand if it is a good idea or a wrong one.

    Related to expansion of Universe we can describe it as an increase of "amount of vacuum" with time expressed in m3. If we apply the Hubble constant (70.8 (km/s)/Mpc) to radius of observable Universe (14 Gpc=14,000 Mpc=46.5 billion light-years) we can say that the radius of Universe is bigger with 991,200 Km with every second past.
    That mean that in every second the volume of Universe is increasing with 9.64*1063 m3. Some consider that, the vacuum have an energy density of about 10-9 joules per cubic meter. So, we can say that in every second an increase of total energy of Universe exist equivalent with 9.64*1054 Joules. This is almost 6.02*1073 eV in every second! A lot of energy.

    Because I believe in conservation of energy at Universe scale, I asked myself where can that additional energy come from.

    And I remembered something that I read sometime about black holes: it does not conserve some properties of falling matter. Just spin, charge and mass (rest mass) are conserved every other properties are lost. Then I tried to read more about what is happening with kinetic energy of falling matter. And if I understood accurate, GR said that because for an external observer the falling matter never arrive inside BH, its kinetic energy is not transmitted to BH. This KE is just lost for the Universe (all what is outside that BH). Reading more I understood that for almost all BH the falling matter have relativistic speed (because in time almost all BH increased its spin to the limit accepted by GR), so that mean a lot of KE involved.

    But, the BH is just one solution of GR ecuations. So, I start to read about while holes, the other solution. And I found not just WH is a time reversal for BH but that WH acts as a source that ejects matter from its event horizon. So, if WH really exist it act like an repulsive force in its near proximity and like an attractive force through it gravitation effect at larger scale.

    Then I tried to figure how it Universe look out at large scale. And I understood that it is like a soap foam with a lot of bubbles at very different sizes where the ordinary matter is organized in super clusters representing the "skin" of the bubbles and inside that bubbles large voids exist.

    Combining all above things now can I explain my idea.
    The expansion is the result of BHs falling matter. Its KE is not lost but is returned to "the Universe" through the WHs. That WHs doesn't eject ordinary matter, instead the KE is replaced with ... vacuum, the energy density of that vacuum to be more precisely. This new vacuum create a pressure on ordinary matter pushing it away from WHs in all directions and creating the foam structure. This is what we see like dark energy.
    Inside of that great bubbles such "vacuum fountains" are ejecting a lot of vacuum, there acting not just one but maybe more WHs because that places represent places with a very low amount of normal matter (maybe none ordinary matter except photons and neutrinos) and is a favorite place for WHs.
    Maybe this "vacuum pressure" create on bubbles surface (the place where ordinary matter exist) a real pressure, keeping matter more dense and creating the illusion of dark matter presence. That vacuum born maybe act like a fluid jet creating strange effects, like a very strange dynamics of bubble skin (I read that our local group is moving relative near groups with http://www.dailygalaxy.com/my_weblog/2009/03/mystery-of-the.html" [Broken], or I read that at the edge of observable Universe some super cluster are moving like something very large outside the Universe are attracting them, etc.).

    Why is expanding accelerating? Because we can understood the galaxies around supermassive black holes from its center like an accretion disk, the amount of falling matter increasing in time. The expansion stared just 5 billions years because the previous amount of falling matter in all BHs from Universe was not enough to create expansion.

    So, what is wrong with this picture? For me, looks like make sense. But who I am (in cosmology) to claim that I am right? Maybe above exist a lot of misconceptions or even errors.

    But if someone can help me to calculate the total KE/per second of entirely falling matter in all BHs from the Universe (piece of cake, isn't it?) maybe the result it will be somehow similar with what I calculated at the beginning of this post. And this can be a minimal proof that maybe I'm right.
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Dec 17, 2009 #2


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    First question: Why do you believe in energy conservation at the Universe scale? There is no timelike killing vector for the FRW metric.
  4. Dec 18, 2009 #3


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    One way to think of it is as coming from gravitational potential energy.

    This is a really good treatment of the status of energy conservation in General Relativity: http://math.ucr.edu/home/baez//physics/Relativity/GR/energy_gr.html
    Last edited: Dec 18, 2009
  5. Dec 18, 2009 #4
    I am not used the word "believe" accidental. It means that I don't have a mathematical explanation.
    Perhaps all is coming from what I understand as energy: potential action. Gravitational potential energy means that a mass object can get kinetic energy (can be moved), KE of an object means that it can generate other kinds of energy (thermal radiation for instance, after a collision), etc. All kind of energy offer some possibilities of action. And, for me, all that amount of possible actions are finite and constant with time at Universe scale. This is why for me "nothing is really born, nothing is really lost, everything is transformation".
  6. Dec 18, 2009 #5
    First, the link is very interesting. Very. But before make remarks about it I must try to understood what is there more deeply.

    Second, I don't understand how can gravitational potential energy to generate vacuum. What do you wanna to say?
  7. Dec 18, 2009 #6


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    It's not generating vacuum per se. It's a statement that the energy increase of a comoving volume of dark energy as time progresses can be thought of as coming from a decrease in gravitational potential energy (which becomes more and more negative).
  8. Dec 18, 2009 #7
    Thank you, I never hear about that.
    I think it is not your statement. Can you tell me where I can read more about this?
  9. Dec 18, 2009 #8


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    Unfortunately I don't know of any good treatments of it online, but it stems from the Hamiltonian formulation of General Relativity (in the more frequently-used formulation, gravitational potential energy is not considered, and so energy is not, in general, conserved).
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