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Big Bang From Black Hole. Each Black Hole creates a New galaxy?

  1. Aug 23, 2009 #1
    So I am defiantly no scientist and I don's know much so if I jump around with my knowledge im sorry. If I am wrong, correct me for that is why I am here.

    It has been said that the black holes take in everything and anything which comes to a miniature 'ball' for say. If what I know about black holes are true then all time and space becomes irrelevant and it can go somewhere we cant even imagine. If that information can enlarge back up because you cant destroy to a level, then wouldn't information be jumped out another side? It would seem like a explosion from a single point like the big bang states. Life can be started in a infinite space. Could we ever know? For the area would be so unknown its for from imagination.

    So my question is, could this be possible or is this even reasonably stated?
     
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  3. Aug 24, 2009 #2

    Chronos

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  4. Aug 24, 2009 #3

    marcus

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    Yes it is possible and the possibility can be reasonably stated----put into mathematical form so you could run a computer simulation of black hole bounce. But so far there is no confirmation of that possibility. It is merely a reasonable conjecture which can be stated.

    Chronos has given you a link to an article that contains (on four or five pages) what is probably the clearest statement of a form of this conjecture which has some empirical content---some aspect that could be tested and either shown to be false or not shown to be false. The article is somewhat technical however.

    There are popular (and also middle-level) books that discuss this idea. Often mixed in among some other ideas about what may have led up to the big bang. You sound like someone looking for a non-technical discussion.

    So here is a new popular book that talks about this idea among others. You can get your public library to order a copy, if it does not have it on the shelf already.

    Brian Clegg
    Before the Big Bang: the Prehistory of Our Universe
    https://www.amazon.com/before-Big-Bang-Prehistory-Universe/dp/0312385471/
    This book just came out this month (August 2009). The amazon page allows limited browsing. Look in the index for "Smolin" and see which pages come up, then browse those pages. If you need help finding the discussion of this black hole budding new universes business, ask for help.

    There is also an earlier (1998) popular book devoted to this idea
    Lee Smolin
    The Life of the Cosmos
    You can look it up at amazon and you can probably find it at the local public library. It is written for general audience but not as light reading as Brian Clegg.

    There are also some middle level books, not popular but on the other hand not full of equations, mostly explaining things in words.
    These middle level books will typically devote a chapter to this idea, among other chapters discussing other ideas.
    They refer to one version as "Cosmic Darwinism" (because it involves universe regions reproducing or approximately (but not exactly) replicating.
    Or they call it "Cosmological Natural Selection".

    One middle level book like that is a collection of essays by mainly prominent people including Nobelists, edited by Bernard Carr, called
    Universe or Multiverse?
    You can also look that up at amazon.

    The best middle level book with a Cosmic Darwinism chapter is one which is now expected to come out March 2010, a collection of essays by top people, edited by Rudy Vaas, called Beyond the Big Bang: Prospects for an Eternal Universe
    You can find that on amazon, but the publishers own page about it is much more informative so I will give that link.
    http://www.springer.com/astronomy/general+relativity/book/978-3-540-71422-4
    Table of contents here:
    http://www.springer.com/astronomy/general+relativity/book/978-3-540-71422-4?detailsPage=toc
    Reviews by people who have read advance copy:
    http://www.springer.com/astronomy/general+relativity/book/978-3-540-71422-4?detailsPage=reviews
     
    Last edited by a moderator: May 4, 2017
  5. Aug 24, 2009 #4
    Even though this could be the start of our existences and others we don't know about, the beginning of information is hard to think.

    Thanks
     
  6. Aug 24, 2009 #5

    marcus

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    Maybe you do not want to be burdened with more puzzling and difficult ideas, and I should let the discussion be as it is. Let me know if that is the case and I'll be glad to stop.

    Indeed there are hard-to-think ideas ideas here. You are talking about the research field called Quantum Gravity (QG) and its specialized application to the early universe called Quantum Cosmology (QC).

    In this research they quantize general relativity (GR, the classical 1915 theory of gravity as dynamic geometry). Quantize does not mean 'divide up into little bits'. In this case it means to switch over to a mathematical model of a type where there is controlled uncertainty and indeterminacy. Reality is described with wavefunctions which are a bit like probability distributions---uncertainty can then be controlled by equations which govern the wavefunctions, but can never be entirely eliminated. Switching over to that kind of representation is called quantizing. A theory which has not been quantized yet is called "classical".

    When classical GR is quantized you can get socalled "quantum corrections" which become significant at very high density. Because of this some QG and QC models predict that, when density gets above a certain level, gravity behaves as if it repels instead of attracts.
    As if matter does not want to be pinned down beyond a certain point. When it becomes so dense that gravity overwhelms all other forces then gravity itself becomes repellent, and reverses its force, until there has been enough re-expansion that the density is no longer so high.

    This is one of those ideas which are very hard to think. And it also might not be true. It is true in certain QG and QC models but these models must be tested (by predicting observable features in the early universe background light which we can then look for and either find or not find, as a test).

    However in a subtle way this hard-to-think idea of repellent gravity responds to your comment about information.

    That is why I find your comment about information so interesting.

    In case someone else is reading this thread, I will first state a controversial idea in a compressed form (for them) that you might possibly not understand, and then I will translate into normal everyday language (because in your original post you claimed layman status.)

    Gravity temporarily reversing sign resets the entropy clock.

    This is a controversial idea that relates to some speculations by Roger Penrose. The black hole bounce scenario involves a seeming paradox, or several paradoxes. The whole topic is still in flux---reasonable people can have friendly arguments about it. It's not settled, but it is interesting. It may take a day or two before I can continue this discussion. Anyway thanks for raising a hard issue and giving cause to reflect.

    BTW as a matter of language it wouldn't be a new "galaxy"---a big bang would create a new spacetime region with lots of individual galaxies eventually condensing out of the matter cloud.
     
    Last edited: Aug 24, 2009
  7. Aug 24, 2009 #6
    Marcus don't stop for I only know what I've been told and that is not a lot. Hopefully more people would find interest in this and jump in on the discussion.

    I also don't know terms so I can only use what I know. So hopefully it is readable.

    I have also thought about what happens when a black hole closes. The things that have been sucked up by it falls in cone shaped from the opening. The cone goes in a area were 'our' time and space is irrelevant. So the things that fell become a infinitely dense ball that are in a area where our time and space are not there. It would fall out into its own 'area'. Personally I would think that after a black hole closes from us it has to open somewhere. Once it closes the dense ball of matter must explode after the gravity of the black hole releases it.

    I was thinking that we must not be the first for there is a lot of things in our galaxy and further. Plus if we are not the first it would explain why things, such as our planet, are so old. Its just a piece of a 'area' beyond us.

    Still it is a far fetched idea and I don't know enough to prove it. I just try to bring together what I know to fix each other.


    Edit: The theory of gravity repels at a certain density can also be brought into what I am talking about. Once all that matter forms it is beyond dense, so the gravity of a black hole repels all that matter out into , what i would think, the opposite of a black hole. So it would look like a cone but instead of bringing the matter in to a point, I would think it would expand it to the new area.
     
    Last edited: Aug 24, 2009
  8. Aug 24, 2009 #7

    DaveC426913

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    I think you misunderstood the OP.

    I don't think he was commenting on your post; I think he was saying the beginning of the universe and the beginning of information is hard to conceive of. In his OP, he was talking about destruction and conservation of information.
     
  9. Aug 25, 2009 #8

    Chronos

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    Information theory [eg Shannon entropy] is a truly fascinating approach to theoretical physics. I think this is one of the best probitive tools currently available, and amenable to computer modeling. A quantum computer may someday do what humans have been unable to do - produce a viable TOE. IT has not yet modeled a 'theory of everything', but has constrained the parameters to an amazing degree. I'm a big fan.
     
  10. Aug 28, 2009 #9
    Hi, I am also not a physicist, but I was under the impression that Hawking's findings in 2003 made that scenario unlikely. I know Prof. Kaku was fond of speculating about the idea that a big bang created a new universe in the form of a corresponding white hole, but again, i thought that the consensus was know that this was not likely. Or am i talking about an entirely different idea here?
     
  11. Aug 31, 2009 #10
    This is plausible in my mind for the start of us.
     
  12. Sep 4, 2009 #11
    My idea is not so much A Big Bang From A Black Hole, but A Big Bang In A Black Hole and from then on the Black Hole becomes a White Hole having the "same" event horizon. Could it not be a compacting/bouncing domain inside before, while expanding after, all within one dynamic event horizon? Before the bounce there could be a net outflux to the event horizon while after there could be a net influx? So IMO we (now) could live in a White Hole, inside the event horizon? The cosmological principle does not hold (though it looks like that, if you are an observer in just a too restricted (observable) domain.) My hopes are that LQC will reveal many things around bounces which IMO are not naked.
     
  13. Sep 4, 2009 #12
    Hey could you explain this part a little more elaborately.
    Do you mean the degree of uncertainty is controlled or is the areas of uncertainty/indeterminacy?

    RESETS???
    You mean the universe goes into superfreeze?
     
    Last edited: Sep 4, 2009
  14. Sep 4, 2009 #13

    marcus

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    Raknath,
    What I said was in response to Philose who said
    Philose on his own came up with an idea similar to Smolin's CNS---a spacetime region branching, reproducing itself via black hole big bangs. He was thinking about it in general nontechnical terms. So I tried to give as complete and honest a response as I could without putting him off by excessive technicality.

    You are asking questions on a different plane, now. You want more detail. Everything should be said in a different, more precise vocabulary. We might need to start a new thread.

    There are various different approaches to QG. Which one or ones would you like to know about? What would you like to know?

    About discretizing---if that is an issue for you. In Loop the basis is a smooth manifold. You build on that. The math model of space is not divided up into little bits. The math model of space time is also not divided up into little bits.
    However certain observables, corresponding to geometric measurements, are represented by operators on a hilbertspace. These operators have discrete spectra. In that sense the continuum is smooth but like "energy levels" in the hydrogen atom when you make a measurement of something you can get discrete levels (like of area).

    The situation in Loop turns out to be consistent with Lorentz invariance, i.e. with special rel. Rovelli has a 2002 paper about this. If you want a link please ask.

    In another approach, Triangulations (see the SciAm article in my sig, by Loll) the basic spacetime is also a continuum. You divide it up, for convenience, into little pieces, but then you let the size of the pieces go to zero. You don't imagine that space is itself divided up. You just use the division as a temporary tool for calculation and for computer simulations of universes.

    I hope that replies to your concern about discreteness, or space being made of little bits.
    In QG it ordinarily is not (Atyy pointed to some variant QGs where it is little bits, but that isnt typical).

    Then you had a question about entropy.
    ================================
    There is a serious technical issue about entropy and the Second Law re bounce cosmologies. I can't resolve it. Penrose pointed out the problem and I don't quite follow either his definition of the entropy of the gravitational field or his extension of the Second Law to cover this case. It may be that he does not actually have a rigorous well-founded argument. But I've heard him make the argument in person, and also several times in video lectures. The best I can do here is to discuss it at an intuitive level.

    The key thing there is how one defines the entropy of the gravitational field. As I recall, according to Penrose low entropy corresponds to a smooth uniform gravitational field---before any clumping/coagulation has taken place. The blank even field is the state of highest order, and as stars and galaxies and clusters of galaxies curdle and coagulate it represents increasing disorder in the grav field. Increasing grav entropy.

    This may seem paradoxical: the entropy of matter behaves differently--- picture gas in a box. If it starts clumped in one corner that is low entropy and as it spreads out uniformly to fill the box evenly, the entropy increases. Penrose stressed that, visually, gravitational entropy behaves in a way that is opposite to matter entropy.

    Now he says: in a bounce you have a bumpy disorderly geometry (an old universe where matter has condensed into stars) that collapses and produces a smooth blank expanding geometry---it looks like you have gone from high entropy to a low.
    =================

    I have several questions about this. One is, who is the observer? I think measuring entropy implicitly requires an observer and the Second Law says that the observer will (almost) never see entropy decrease. In a bounce, the observer has to be either before or after and neither Mr Before or Mr After will actually witness a violation.

    I also have a problem with how Penrose defines the entropy of the universe because I'm used to imagining an enclosed system from some outside observer's perspective and universe doesn't provide an outside.


    But the main difficulty I have is that this whole doctrine assumes that gravity is always attractive! That is the only reason you can say that the clumped bumpy uneven field is higher entropy than the smooth. Because since gravity is attractive, as time goes on there will always be more and more clumping and dissipation of energy as lowgrade heat.

    But the tables are turned if gravity briefly turns repulsive. (This occurs in quantum cosmology models at very high, near-Planck, density.) In that case everything wants to spread out evenly instead of clump. The equilibrium high entropy state is then the uniform one---which however counts as low entropy when the system expands enough for gravity to become attractive again.

    I think one way to sum this up is to say that entropy is itself observer dependent. It depends on what standpoint. Is the observer before the bounce looking into the future, or after the bounce looking back into the past. Perhaps neither one can see a violation of the Second Law. And if noone sees a violation, then the Second Law was not violated.

    I'm not sure about this. I am speculating to some extent. These are just some things to think about. Perhaps we can continue later, as time permits.
     
    Last edited: Sep 5, 2009
  15. Sep 5, 2009 #14
    This is very interesting! I have been thinking that gravity must have a repulsive term that is so small that it is not measurable at normal distances between objects, but at very great distances (inter galactic) it overwhelms the attractive nature and allows the universe to expand. Newtons Law of Gravity states that the attraction is proportional to the product of the masses and inversely proportional to the square of the distance between their centers. Distances within galaxy clusters are short enough to maintain attraction greater than repulsion, but the very great distance between galaxy clusters the repulsive force is greater than the attractive force, providing expansion. No dark energy required!

    Now the "big bounce" may also be explained by this repulsive force being greater than the attraction force at very small distances or very large masses that would occur at a place where all matter were condensed to an extremely small space with a huge density.

    I believe this concept could also explain so called "dark matter" as the distances in galaxies gets to the point where the two gravitation forces start to balance out each other.

    I am not a cosmologist or physicists just an old engineer with an interest in cosmology that has a hard time understanding dark matter or dark energy.

    PRD
     
  16. Sep 5, 2009 #15

    marcus

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    Danforth, thanks for your reaction. I'm happy to see other people wondering about these things and getting interesting ideas. There are aspects I don't understand well enough to comment on. (Except at an intuitive level, see the discussion of bounce+entropy just now.)
    Maybe we will get some comment from others.
     
  17. Sep 5, 2009 #16
    Thanks for your kind comment, Marcus. If the law of gravity does have an attractive term that we understand and see everyday as did Newton and also a repulsive term that is so weak that we do not normally "see" it except at very great distances between galaxy clusters, then there should be a point in distance where they should balance out to a null effect. What would happen at this distance? It would be an unstable place where matter could not exist in equilibrium, as a pencil standing on its point, a little further out would be repulsed and a little further in together would be attractive. Perhaps our scientists can somehow observe this phenomenon in the future.

    Should this be a topic for another thread? I seem to have diverged from the OP.
     
  18. Sep 5, 2009 #17

    marcus

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    It's always at the mods' discretion. We don't always have to be sticklers about staying on the exact topic. In this case Philose, the original poster (the "OP") seems to be satisfied and there is not a lot of debate surging in the thread. So it wouldn't be likely to cause noise and confusion to vary the topic a little, in this case. It might as well AFAICS continue over into neighboring topics. Maybe you are the only one interested in continuing it. So why not do so?
    But I'm not a mentor--and they decide.
     
  19. Sep 7, 2009 #18
    Basically what you are saying is that in an higher state of order the gravity would be uniform?
    Am i right in understanding this?
    How exactly does gravity vary with entropy. I mean as in intuitively understand it, gravity is a measure of association between objects and entropy would be the association wrt to heat content. How does heat per se relate to gravity?

    So does this also have a converse a state of high order will lead to a uniform detectable gravitational field? Lets take the case of an open and globular cluster. What we say then is that in a globular owing to a better packing of stars we have a more ordered gravity field an not the the other way around?


    Whats gravitational entropy? hows it different from the usual entropy?


    I am sorry can i clarify that entropy can be a function of enthalpy and gibbs free energy and need not be measured as an observer isnt it? It is intrinsic and is based on elements i mean one cant measure it as a one measures force can he?

    if you feel the disc is getting too non generalised please message me on private messages we could exchange this on emails :smile:
     
  20. Dec 21, 2009 #19
    So then, does that mean that gravitational entropy is opposite of matter by wanting to collect at a point at the center of itself rather than disperse evenly?

    One possible explanation for the gravity flipping to repulsion could be that since space time is affected by high gravity, at a certain density(or whichever is the correct term) the point in space-time at which the gravitational entropy has been centered is moved or changed.

    Say for example that the black hole is like an asymptote, so the exact point where the center is occurring is undefined on a space-time graph. If the center of the black hole(also the point of gravitational entropy) is undefined, then where is it? And if it is not there, then the point of grav entropy must not be there either, and this would cause the gravity to appear to change to repulsion, while it could still be attracting, just with the point removed, or just _________ (could be a magnitude change or who knows what), it would disperse rather than collect, just like gas in a box could not disperse if the box was only one point, or undefined.

    As to where the material or gravity(or space-time) entering the black hole ends up, it could emerge in the our universe at the point of origin, or as dark matter/energy in the least dense areas(like sea floor spreading), or to the next universe which currently has spacial dimensions and all of the matter leaving this one, but not yet a time dimension which possibly depends on an observer to become defined.

    Just throwing some thoughts out there; I enjoy this topic.
     
  21. Dec 22, 2009 #20

    Chronos

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    There is a school of thought suggesting gravity is an entropic, back reaction to the presence of matter/energy in the universe. I don't think wormholes work, they appear unstable. Do black holes provide a convenient 'shortcut'? Unknown. I think there are causality issues, e.g. - if a 'mother' black hole evaporates, what happens to its decendent universes?
     
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