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White holes and the big bang

  1. Nov 20, 2004 #1
    I read this about a white hole and had some thoughts:

    "The short answer is that a white hole is something which probably cannot exist in the real universe. A white hole will turn up in your mathematics if you explore the space-time around a black hole without including the star which made the black hole (ie. there is absolutely no matter in the solution). Once you add any matter to the space-time, the part which included a white hole disappears."

    Here's thougts, before the big band, there was nothing. Since there is no mass, this gives rise to a white hole. The white hole, or anti-black hole, spits out matter producing the big bang.

    any thoughts?
     
  2. jcsd
  3. Nov 20, 2004 #2

    Mk

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    lol, my mind is just like... yeah.
     
  4. Nov 21, 2004 #3
    From what astrologists know, particles were created after Big Bang from energy.
    For more information, read The Brief History of Time from Stephen Hawking.
     
  5. Nov 21, 2004 #4

    Garth

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    Is Stephen Hawking an astrologist? What star sign is he?

    I actually like the idea of a
    - ever since Glen Miller!

    To be serious, the idea that the Big Bang might be a "white hole" has some credability although it has to be treated with caution. The Schwarzschild solution of Einstein's GR field equation is a local spherically symmetric solution, the Big Bang comes from the cosmological, homogeneous and isotropic solution. They are not the same. A quantum gravity might indeed lead to a "bounce" at the singularities in both but that would be "shooting in the dark" at the moment, so be cautious.

    Garth
     
    Last edited: Nov 21, 2004
  6. Nov 21, 2004 #5
    Thanks for the responce Garth, can you explain what you mean in less scientific words? I'm very interested in this topic but I dont think I know everything about "Schwarzschild solution" or what you mean by "cosmological, homogeneous and isotropic solution."

    Thanks
     
  7. Nov 21, 2004 #6

    Garth

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    The theory of General Relativity really is Einstein's field equation. This applies at every event in the universe and links the second derivatives of the way spacetime curves to the distribution of density, enegy and stresses at those events. To make any sense of it you have to solve it, i.e. integrate the tensors twice and apply suitable boundary conditions.

    There are only two relatively straight forward cases.

    The first is that in which the only mass you consider is spherically symmetric and static, the density is a function of radius only, such as a mass like the Earth or the Sun; this is the Schwarzschild solution.

    The other case is when the density is smeared out into a representative gas of the same density, temperature and pressure throughout the entire universe, density is a function of time only. This is the cosmological case and depends on the two assumptions that the universe is isotropic (it looks the same in all directions) and homogeneous (it is the same at all positions at any particular epoch).

    The first solution is used in the local tests of the theory and the second solution has been used in all cosmology for the last seventy years or so.

    Garth
     
    Last edited: Nov 22, 2004
  8. Nov 21, 2004 #7
    How does what you say tie into what I said?

    how come?
     
  9. Nov 21, 2004 #8

    Garth

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    I understood your orignal suggestion to be that the Big Bang was in effect a 'white hole' in a 'nothingness'. I was just pointing out that as the black hole solution was a local phenomena embeded in a cosmological background, you could not automatically apply the white hole equivalent, which is a very speculative concept in the first place, to the universe as a whole. They are two separate and different solutions to the GR field equation. You have to be very cautious about such extrapolations.

    Garth.
     
  10. Nov 22, 2004 #9
  11. Nov 23, 2004 #10
    thanks, I read about that already :)

    Garth, I still have trouble understanding what you are saying. I'm very sorry but I an not very knowledgeble in this field. Especially "black hole solution was a local phenomena embeded in a cosmological background." Are you saying that there has to be "space" for a black hole to exist, and since there is no space for a black hole to exist, there cant be any white holes?
     
  12. Nov 23, 2004 #11

    Garth

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    UrbanXrisis,
    Sorry if I have not made myself clear.
    The theory of GR is based on some very profound and rather simple principles. The model of a rubber sheet with a bowling ball making a bent in the middle is a good way to think about how mass makes space-time 'curve'. However to solve GR’s field equation for a particular situation leads to some very difficult and complicated equations - grad school stuff.

    One of these situations is the solution for the gravitational field around a spherical mass such as the Sun. This is called the Schwarzschild solution. It leads to the understanding that if the gravitational field is strong enough then even light would not be able to escape from a boundary around the mass and so it would form a ‘black’ object. Furthermore inside this boundary, called the event horizon, the crushing gravitational force could become so great that no force is known that could withstand it. Therefore the massive object would contract down under its own gravitational field and keep going, because there is nothing to stop it, until it became a singularity at the centre, something with zero volume and infinite density. Therefore this object is known as a Black Hole

    But if the object forming a black hole was rotating then the singularity at the centre becomes not a point but a ring, an annulus. And the space-time within the event horizon not only funnels down into this central ring but continues through it opening out somewhere, and ‘some-when’ else!! This theoretical solution to the black hole situation then led to the idea that a black hole in one part of the universe might open out into a White Hole in another part.

    It is tempting to suggest, as you did, that such a white hole might be the beginning of another universe. However as the black hole was only a solution within this universe, and the white hole a speculative extrapolation of that solution, we cannot assume that the white hole actually exists in this universe let alone in another one!

    I hope this has helped! As I said in response to a post of yours in another thread – keep reading about the subject you will find it fascinating!

    Garth
     
  13. Nov 23, 2004 #12
    White holes in the context of baryonic matter passing through the Cauchy horizon was discussed recently on the String/LQG subforum based on a recent series of papers by Hamilton, etal. Here is the link to his last most comprehensive paper:

    http://www.arxiv.org/abs/gr-qc/0411062

    He considered spherically symmetric, charged black holes. There are a set conditions where dark matter is streaming into the hole and previously captured baryonic matter having been repelled by the charged central region, is streaming outward. The baryonic matter can then pass through a Cauchy horizon and presumably into a new universe as a white hole.

    These conditions do not last long- just until the central region accumultes enough mass that the center of mass of the entire local system is moving inward rather than outward.

    Richard Ruquist
     
  14. Nov 23, 2004 #13
    Now we have white holes? what next pink or green holes?
     
  15. Nov 23, 2004 #14
    So a white hole cannot exist because there need to be a black hole. And a black hole cannot exist unless there was already a universe. Am I getting this?

    not sure I understand why it has to be a ring.
     
  16. Nov 24, 2004 #15

    Mk

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    Mhmm, why's it a ring? Its a long explination, but check out last month's Scientific American.

    Sí, white holes only exist when there is a brother black hole, and there can't be a black hole unless there was already a something, like a star or a universe. Here comes in the "Many Worlds" theory of parallel universes, and the theory where energy and matter bubbles up from nowhere...

    Ha, ha, wow, tumor, you're gonna love this:
    http://www.wired.com/news/news/technology/story/19554.html
    http://msowww.anu.edu.au/~pfrancis/pink/
    http://www.astro.ucla.edu/~kaisler/articles/event_horizon/pinkhole2.html
    Actually there are pink black holes... they've found over 100.


    Ok, another one, that you're gonna love... grey holes, which happen to be pretty much regular black holes, when information escapes from them, they can be called grey/gray.
    http://www.nytimes.com/auth/login?URI=http://www.nytimes.com/2004/07/22/science/22hawk.html


    Near-extremal black hole are close if not at the minimum possible mass to be a black hole.

    If black holes have infinite gravity at its center, and suck in everything inevitabley within its vicinity, why wouldn't white holes be made of exotic matter, and have negativley infinite gravity at its center, and repel everything within its vicinity instead of spew stuff out? That would also obey the 2nd Law of Thermodynamics.
     
    Last edited: Nov 24, 2004
  17. Nov 24, 2004 #16
    big bounce- bouncing singularity- new spacetime- not just a white hole made out of matter/energy- more of an "anti-hole"- it's un-holey- :tongue: :devil: see Smolin's CNS
     
  18. Nov 24, 2004 #17
    Actually, I was just thinking about it and using logic, I can undersatnd why it has to be a ring. Would it be because if the constant rotation of the mass at such a high velocity right? What if the mass wasn't rotating? Would it then be a ball?

    And how can black holes look pink when there are dark matter?
     
  19. Nov 24, 2004 #18

    turbo

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    These articles about "pink" black holes are a bit inaccurate, as articles about astronomy in the popular press often are. The pictures are pictures of quasars, which are commonly believed to be powered by large black holes that are sucking up local mass at a prodigous rate. The area around these quasars is therefore very energetic. Most quasars are brightest in the shorter wavenlengths and look bluish-white, but some have been found that are pinkish in color. This color originates from the excited field surrounding the quasar's black hole and does not have anything to do with the color of the central black hole itself.
     
  20. Nov 25, 2004 #19

    Mk

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    Questions!!!

    Umm, I didn't quite understand that...

    Is it that the black holes are powering the quasars, or the quasars powering the black holes? lol, plowing the ZPE field

    Hmmm, black holes are not made of dark matter, they appear black because once light falls in its reach, it doesn't leave.

    "'Все Перемещается', 'Everything moves'" -Russian Proverb
    I don't think it can not rotate. The two known super-massive black holes in the center of the Milky Way galaxy... there's a ball there, the core. I never thought about that. Good question. Maybe because of the overwhelming majority of matter surrounding it?

    Can black holes get full? I really can't imagine a black hole sucking up the entire universe, expanding on that: It doesn't absorb radiation, so why does it absorb all light? Would there be sufficent cosmic rays left to evaporate it after a black hole would absorb everything in the universe? When two black holes collide, why does it create a wormhole, and not another super-massive black hole? What happens when a black and white hole collide? They cancel each other out, and what's left is the extra matter from the white hole or, a smaller black hole or nothing left? Or since black holes can't get full of matter, would the black hole just suck up the white hole, therefore the white hole would be inside the black hole, and the black hole would have infinite mass and gravity, creating a rip in spacetime? Or would this be a Schwarzschild wormhole? Is the center of a black hole hot, because of compression? If white holes are made of exotic matter, with negative gravity, would it therefore be an exotic matter black hole? If black holes are constantly evaperating what is the product of evaperation? It must be radiant energy since the black whole would suck it right up, but if the black hole sucks up radiant light energy, why not all energy within vicinity? What about Hawking's proposed, black holes do not evaporate but instead create wormholes? But then how does Hawking and X-ray energy escape?
    This doesn't sound right... would a black hole give off enough cosmic rays to evaporate itself?

    Do black holes emit radiation in the form of light as well, though it doesn't escape? If an object is caught within the Schwarzchild radius, that doesn't make it a black hole as well, does it? If so, there's not two black holes because the parent one eats up the daughter hole? Again... why not a ball?... hmmm... does it have something to do with its axis of rotation?

    Ok, so maybe a black hole can "not rotate."

    How do the particles escape the Schwarzchild radius Wouldn't a particle have to be accelerated to velocity of light?

    Since the Earth has a mean radius of 6371 km, its volume would have to be reduced 4 × 1026 times to collapse into a black hole. For an object with the mass of the Sun, the Schwarzschild radius is approximately 3 km, much smaller than the Sun's current radius of about 700,000 km.
     
    Last edited: Nov 25, 2004
  21. Nov 25, 2004 #20

    Chronos

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    Black holes are the power source.
    No reason to think so.
    It absorbs all radiation, including light
    Cosmic rays have nothing to do with black hole evaporation.
    No wormhole, just a bigger black hole.
    Since white holes are purely speculative, and probably non-existent, no point in worrying about that until one is actually found.
    Unknown and inconsequential, the radiation could not escape.
    They are formed outside of the event horizon.
    They don't, the ones that escape are formed outside the Schwarzchild radius.

    Just to clarify, the high energy radiation observed in the vicinity of black holes is emitted by infalling matter. This occurs outside the event horizon. Hawking radiation is created just outside the event horizon. It is, however, much too faint to be detected directly. The only exception would be a mini-black hole, say a few billion tons [which Hawking theorized may have formed in the very early universe] which would be extremely hot compared to their leviathan cousins. It would also have to be very near earth [within a light year or so]. Even though they are hot, the radiation is in the form of high energy gamma rays. Relatively few photons need be emitted for them to pay off their thermodynamic debt.
     
    Last edited: Nov 25, 2004
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