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Bang RIP, Bang RIP

  1. Oct 21, 2007 #1
    The preferred (Big Bang) theory is that the universe started as a super hot, super dense dit that was the size of an atom or less.

    The end of the universe (Big RIP) theory states that space will expand to the point that eventually every atom -- or maybe even every subatomic particle -- will start speeding away from its neighbors as the space between matter expands at a faster and faster rate.

    So, these tiny little dits of matter will be thrown at incredible speeds through space, as space expands exponentially. That increase in speed should impart a lot of energy into those dits of matter. That energy should be converted to heat and add to their mass, as those particles approach the speed of light.

    Eventually, each of these particles could become a super hot, super dense dit -- just like what they say the universe started as.

    Is it possible that we'll undergo a quantum expansion, where every particle of matter in the universe becomes a new universe with a big bang? Has any scientist already proposed a theory like this?
  2. jcsd
  3. Oct 21, 2007 #2
    I believe the accepted theory is that the Big Bang resulted from a sudden imbalance within the "super atom" where it all of a sudden "blew up", faster than the speed of light. The imbalance occurred when the gravity holding the atom together all of a sudden was made insignificant to the repulsive force of that atom. As the universe blew up this fused H with H to create all known elements and then from there celestial bodies etc. started to form. The Universe is still expanding today, all celestial masses are moving away from each other in what is called the cosmic constant (the repulsive force of the universe). From there, two other theories prevail. The Universe is slowing down, and the universe is speeding up. With the former, the universe's cosmic constant will eventually yield to gravity again and collapse back into a super atom. The latter, that the universe as we know will continue to expand forever. The latter I believe is more accepted. So your theory of universe from a big bang within our universe is not accepted, nor do I know of that it's believed to be possible. However there are theories of universes within ours, thus creating the multiverse which is infinite. Thus we are infinitely larger and infinitely smaller than any other universe. As are we infinitely smarter, and respectfully dumber than other life within the multiverse and so on.
  4. Oct 21, 2007 #3


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    There is no accepted theory regarding what the big bang actually was. The big bang is a theory that describes the universe as expanding, and having a beginning, but it does not go on to say what this beginning actually was. It concerns times a small fraction of a second after the "bang," but if we track back further than this, classical GR gives us a singularity; saying that the theory is not sufficient to describe this event.
    What you are talking about here is the cosmological constant. However, this is just one proposal for what dark energy is. (Dark energy being the term used for the thing driving the acceleration of the expansion of the universe).

    We know that the expansion of the universe is accelerating at the present time. However it could start to decelerate in the future.

    This isn't really on topic. The multiverse theory is very new, and I do not know anything like enough about it to comment on it.

    I should also point out to both posters the PF rules regarding over speculative posts, and discussion of non-mainstream/unpublished work. Oh, and as an aside, this thread is more suited to the Cosmology forum.
  5. Oct 22, 2007 #4


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    There is no accepted theory of what caused the Big Bang. In particular there is no accepted theory that says a "super atom" suddenly "blew up".
    Cristo is right about no accepted theory. As a grad student in cosmology he ought to know.
    There are various competing professionally reseached models of what preceded the Big Bang, and people are currently trying them out to see how they work, with computer simulations and so on. But none of them have anything remotelyi resembling what you are describing as far as I know.
    You might like to read some of the actual research papers and get a more accurate picture.

    Standard cosmology (LambdaCDM model that nearly every working cosmologist uses) does not lead to Big Rip.
    Some scientists have fantasized about Big Rip but in recent years the idea has gotten less popular. The data coming in seem to weigh against it.

    Standard LambdaCDM cosmology involves a beginning of expansion (loosely called Big Bang) but it does not say what preceded that or what caused it. There are various inflation scenarios, but no preferred theory of what started it off.

    I don't know where you got the thing about the universe starting as "the size of an atom or less". Sounds like a popular science book.

    LambdaCDM is the preferred model, by far. It may be wrong (I am not claiming it is right.) But you can't reasonably say something else is preferred.

    It's OK to fantasize about Big Rip scenarios but don't say they are preferred or accepted by professionals. Everybody is free to fantasize however they want as long as they don't make unsubstantiated claims.

    Personally I like the quantum gravity Bounce model, as a picture of what was going on right before the beginning of expansion---or, in some versions, right before the beginning of inflation. This model is getting an increasing amount of attention in professional journals, in the past couple of years. You might say it is "the latest thing" in pre-Big-Bang theories.

    But because there are COMPETING pre-B-B theories and no single one is preferred or generally accepted, I have to avoid claiming that it's right. Two big names associated with this model are Bojowald and Ashtekar. Keep an eye out for their names, in whatever science news you read, if you want to follow that particular story. Or ask and I or somebody else will give you links to PF threads about their work.
    Last edited: Oct 22, 2007
  6. Oct 22, 2007 #5


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    CuriousGreg -- I mean no offense by this, but you need to take several steps backwards and work on understanding more elementary stuff.

    To get you started, I have two topics in classical mechanics you might want to look at:

    (1) Gallilean relativity -- the point is that things like velocity and kinetic energy are not 'absolute' quantities, but instead depend on your frame of reference.

    (2) Basic thermodynamics -- the point being that notions like 'heat' are bulk properties of matter; they do not make sense for individual particles.
    Last edited: Oct 22, 2007
  7. Oct 22, 2007 #6
    re-Big Bang

    I wrote a supersymmetry theory, what say
    -the cause of Big Bang,
    -susy teleportation,
    -energy and charge breaking,
    -Goldstino as dark matter,

    The color broken QGP state in the Big Bang explains the near infinite energy and the mass of the universe. The break of color gives infinite potential energy for the not white state. If a lone color charge disappears today, the whole universe would turn into a not white QGP again, like 10^10 years ago in the Big Bang.
    The physicists do not use the bosonical superfield propagator to describe the superparticles, everyone calculate with the Feynman graphs. But the bosonical SUSY propagator contains a measurable quantum leap. The leap nature of SUSY transformations appears in the squark decay sq → G + q what should break the color.

    re-Big Bang:
    I find very interesting that a little charge breaking can cause infinite universe contraction and explosion. The disappearance of a lot of color particles give a white noise color and could give a quasi stable, quasi white state.
    The number of vertices relates to the number of discrete time shifts. The contraction continues until all baryon become QGP state. Until k or alpha strong >0 the hadrons move in the central color potential direction. This takes for long time (billions of years) if we collect all baryons. But it’s not a long time for the time shifted super particles.

    The article:


  8. Oct 26, 2007 #7

    Chris Hillman

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    Not so fast!

    Shouldn't this thread be in the cosmology forum?

    Several posters already pointed out various ways in which this characterization of what the Big Bang model postulates is incorrect, but apparently no-one mentioned the most basic: the BB model doesn't say the universe was "the size of an atom", it says that the content (matter, energy density of EM fields, and so on) of the universe was once much denser than it is today.

    This appears to reflect a common misconception which I don't wish to try to explain. Suffice it to say that understanding "kinetic energy in the large" is trickier in the context of gtr than in Newtonian physics.

    That does in fact sound somewhat similar to a somewhat less vague proposal of Roger Penrose.
    Last edited: Oct 26, 2007
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