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No Big Bang? Endless Universe Made Possible by New Model

  1. Jan 30, 2007 #1

    SF

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    A new cosmological model demonstrates the universe can endlessly expand and contract, providing a rival to Big Bang theories and solving a thorny modern physics problem, according to University of North Carolina at Chapel Hill physicists.

    The cyclic model proposed by Dr. Paul Frampton, Louis J. Rubin Jr. distinguished professor of physics in UNC's College of Arts & Sciences, and co-author Lauris Baum, a UNC graduate student in physics, has four key parts: expansion, turnaround, contraction and bounce.

    During expansion, dark energy -- the unknown force causing the universe to expand at an accelerating rate -- pushes and pushes until all matter fragments into patches so far apart that nothing can bridge the gaps. Everything from black holes to atoms disintegrates. This point, just a fraction of a second before the end of time, is the turnaround.

    At the turnaround, each fragmented patch collapses and contracts individually instead of pulling back together in a reversal of the Big Bang. The patches become an infinite number of independent universes that contract and then bounce outward again, reinflating in a manner similar to the Big Bang. One patch becomes our universe.

    "This cycle happens an infinite number of times, thus eliminating any start or end of time," Frampton said. "There is no Big Bang."

    Source: http://www.physorg.com/news89399974.html
     
  2. jcsd
  3. Jan 31, 2007 #2
    I wonder what Hawking and Penrose have to say on this..never mind - they have made enough money with their singularity theorems...can we ask for a refund?
     
    Last edited: Jan 31, 2007
  4. Jan 31, 2007 #3
    Last edited: Jan 31, 2007
  5. Jan 31, 2007 #4
    we only need one universe, one that recycles!

    An oscillating universe, just one, the one we live in, can and I believe does oscillate. The big bang was the point at which the present expansion began. The energy of expansion was barrowed from gravity. After all the stars wink out and radiation ceases, the only energy left is, gravity. Gravity created the galaxies and every thing else. Now, what is left is the relentless force of all of nature, gravity. Then after eons of time this force, the shaper of space/time, begins to bring back together all the mass/energy of the universe. And a period of contraction begins. As mass accelerates and comes closer together the tempature of the universe gets higher. At some critical point, a big bang once again happens. The energy of the original big bang is ballanced, like a debt paid off. The energy of the momentun of the collapse begins another expansion. And the process is repeated endlessly as it always has, no beginning and no end. No something from nothing because there always was somthing. It is like a pendilum, reversing it's energy at the top, and returning to the other side, back and forth. No outside to leak energy to. No friction lost, lost to where? There is no other there. A finite, self contained universe where everythig is always in ballance. As far as I know, no physics we know is violated by this concept. Of coarse the 'big bang' part is the same in both ideas and still needs to be worked out in detail. This is not a new idea of coarse, but one I would like to see examined by people who can work out the details so as to make it possible or not possible. Well it makes the most sence to me. What do you think?
     
  6. Feb 1, 2007 #5

    Chronos

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    Frampton has both insisted upon, and denied the existence of dark energy over the past few years. I suppose that makes him half right, at worst. I don't see any definitive predictions arising from this approach. There are 3 classes of cosmological models that hinge on whether W < -1, W = -1 or W > -1. Unfortunately, all three possible equations of state still allow considerable lattitude for most models. It would certainly constrain all cosmological models [which is always welcome], but forbid only a fairly small number of variations on current themes. This is just another mildly interesting idea that will probably never be testable, IMO.
     
    Last edited: Feb 1, 2007
  7. Feb 1, 2007 #6

    You claim on hand there is no Big Bang, on the other hand, the model you propose is just a cyclic scenario of Big Bang - expansion - contraction - Big Crunch - etc. So your theory does not reduce the Big Bang scenario, only makes it part of a cycle......

    [and another note is that there are good reasons to exclude the possibility of such a scenario, but currently, the arguments for this doesn't come to my mind....]

    PS. And you have simply a wrong notion of the Big Bang, as there is no physical/cosmological claim that the Big Bang theory induces that the universe began (from what?) at the Big Bang (the fictional singularity at the begin of time).
    The Big Bang theory is most simply stated a theory that claims how the universe overall evolves from a denser, hotter and smaller (scale factor) state to one which is cooler, less dense and bigger, and the same theory from which we can conclude that such was the case (general relativity) at the same time disallows us to speak of a 'begin' since that very theory is known to collapse at that point.
     
    Last edited: Feb 1, 2007
  8. Feb 1, 2007 #7
    big bang, something from nothing.

    I never believed the big bang was 'the' beginning, or something from nothing. It is, however, still understood by many people as such. I intended to refut the idea by offering repeated oscillations as a means to rid cosmology of that misconception of the therory. Thanks for your reponse, Robert.
     
  9. Feb 1, 2007 #8
    That is due because cosmologists/physicisists confuse people in believing that.

    This has also to do with the invention of the solution to the Einstein equations, first by Friedman (a russian cosmologist) and later by the Belgian priest Lemaittre. The latter who saw in that a concept of a 'creation' (the Big Bang was then coined the 'cosmic atom' or 'cosmic egg').
    The Catholic church adopted officially the Big Bang theory as part of their creation doctrine. So the catholic church doesn't want to know about eternal/cyclic models, and subscribes only to models of inflation which are not past eternal.

    Nowadays still many scientists publish about ideas of a 'begin' from nothing or from an initial singularity. Which for the general public is understood as that a model of the universe starting from "nothing" is a 'viable' model.
    Therefore the Big Bang theory for most people is identical to a "begin from nothing".

    Which of course for good physical and both philosophical reasons is simply wrong. A begin from nothing or from a singularity is not a scientific concept.
    Such a beginning is said to be Incomprehensible, because it understands being and non-being as absolutely seperate, whereas a proper understanding of being and non-being sees them as two moments of becoming, which necessarily belong to each other and form a dialectical unity.

    See for example:
    Incomprehensibility of the beginning [Hegel; Science of Logic; Doctrine of Being - Remark 4]

    Btw. Not only a cyclic model but also cosmic inflation (which can be past eternal) offer a good, and perhaps better point of view, which avoids the initial singularity alltogether.
    Inflation is already part of the understanding of why and how the Big Bang takes place, and has made testable predictions which match obserations (which at least say, it can't be ruled out).
     
    Last edited: Feb 1, 2007
  10. Feb 1, 2007 #9

    Garth

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    Expansion from a singularity is actually just standard GR cosmology. Hawking and Ellis showed in their "The Large Scale Structure of Space-time" (Cambridge 1973) that if the conditions of their theorems 2 and 3 were satisfied; such as: no closed time-like curves, the strong energy condition holds (i.e. energy density not negative), and a reasonable topology, then there was a past singularity at the beginning of the present expansion phase of the universe that cannot be avoided.

    What actually happened at that singularity, and 'before' it, is open to much conjecture and certainly cannot be resolved before a viable and tested Quantum Gravity theory is established.

    However, it would be erroneous to suggest that the reason an initial singularity was postulated was the dogmatic stance of the Catholic Church. It has much more scientific grounds than that - see Hawking & Ellis for a start.
     
  11. Feb 1, 2007 #10
    Speeking of Hawking..

    Stephen Hawkings "No Boundry" proposal totally eliminates the singularity. He proposes using 'imaginary time' in his book "A Brief history of time". He does not propose an oscillating universe but does say it would expand to some maximum size and then collapse again back where it originated. He used the north and south poles as an illistration saying that the starting and stopping points of this proccess were no more a singularity than are the north and south poles. The book is interesting and makes for good reading. Robert.
     
  12. Feb 2, 2007 #11
    So did Hawking and Penrose say there is singularity or no singularity? Or they are not sure so they say contradictory different things at different times?
     
  13. Feb 2, 2007 #12
    Yes, but I just reflected only the fact the Catholic Church is in favour of such models, and disfavours others.
     
  14. Feb 2, 2007 #13
    So they say there is singularity on the basis of general relativity or quantum theory or both?
     
  15. Feb 2, 2007 #14
    Hawking said that he was now trying to get his fellows to change their minds as he apparently has. His latest work is an attempt to refute the idea of vanishing mass and information in a black hole, as he originally believed happened, applying the 'the sum over histories'. He has done an about face in view of current info, the sign of a great scientist.
     
  16. Feb 2, 2007 #15
    You have more info? Does he apply quantum theory?
     
  17. Feb 2, 2007 #16
    General relativity of course. Cosmological expansion is due to general relativity.
     
  18. Feb 3, 2007 #17
    Hawking

    All my info came from his books and TV programs. The latest TV story on his turnaround on lost info and black holes is work he is currently doing. The results of that are not out yet. He is a cosmologist and would need the use of quantum physics to do that work as thats the physics he and Penrose used in thier long study of black holes. His books are worth reading and easily understood. I recomend anyone interested in cosmology read them as part of their study of the subject.
    Robert.
     
  19. Mar 3, 2007 #18
    Where are the edges of our "Universe"?

    If, and its a big if, our universe is contantly expanding and contracting, where are the edges iof our universe? What is beyond the universe? I have a hard time imagning just pure nothingness, and from what I have read and understand(please correct me if I am wrong, I am neither a Physicist, nor a Cosmologist), it is impossible to actually have nothing. :confused:

    I like to beleive the "We are a speck of dust in another universe" theory.:biggrin:

    However, if anyone wants to help me understand why the big bang, or the infinite universe theory is correct, I am open. Like I said, I am no scientist, and have no formal education on the subject. I am just an amateur astronomer with a huge interest.

    If our universe is flat, which I dont beleive, then why dont we expand right out of our "box"? If its curved, why doesnt it expand like a balloon and eventually pop? Is the cosmological constant really that important? I guess Im struggling with a lot of theories that just dont sound right to me. If anyone wants to explain, Im willing to listen and learn.
     
  20. Mar 4, 2007 #19

    vld

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    Since we are confined to a 3D space we cannot visualise the universe's edges: there are no edges of, say, a 3-sphere. But we can reduce the dimensionality and visualise the expanding 3D-universe in the form of a 2-sphere. If the radius of this sphere is infinite, we have a flat universe case. Nothingness cannot belong to the universe by definition (since the universe is a set of everything that exists, anything elese is not included), so there is no need in imagining what is beyond the universe. By this definition it must be self-contained. Then the fourth-dimension in which it might be embedded is not needed. Mathematically, however, it is sometimes convenient to model a curved 3-space as embedded into a higher dimensional spaces.
     
  21. Mar 4, 2007 #20
    Threeheadedtoad
    The best treatment of a universe that expands to some max. size and then recollapses is in Stephen Hawkings book "A Brief History Of Time". In his book he introduced "The No Boundry Proposal". This idea has a universe that can be best understood by imaginning a sphere with two points like the north and south poles of earth. Keep in mind that this is a tree dimensional example of a four dimensional universe. The universe begins at the north pole as a point. It is no more a singularity than the is north pole. It then expands to some max. size and then recollapses back to a point at the south pole. He did not say that it would then rexpand however.
    This book is easy reading and I recomend you read it. The no boundry proposal is in chapter 8, the origin and fate of the universe.
     
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