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Probability of BB being correct

  1. Apr 9, 2005 #1
    Having read Eric J. Lerner's book ' The Big Bang Never Happened' I realized that the BB theory is not the only possible explanation for how the Universe originated.

    I was wondering if anyone else in this forum had read Lerner's book and what you thought of it.

    Also, what is the consensus on the BB theory. Is the new information from the new X- ray and gamma ray satellites offering more support or less support for the BB. What is the probability the BB theory is not correct? Do you think it will ever be considered the BB Law.
  2. jcsd
  3. Apr 9, 2005 #2


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    The Big Bang Theory is not a theory about the origin of the universe, despite populat opinion.

    The Big Bang Theory asserts that long, long ago, the visible universe was packed into a much smaller volume (and thus was very hot) and subsequently underwent rapid expansion. It does not make any guesses about what happened before this.
  4. Apr 9, 2005 #3
    Lerner hypothesizes the Universe did not undergo any rapid or inflationary expansion and supports his argument with plasma cosmology which makes more sense than many of the BB suppositions.

    Do feel there is any substance to Lerner's hypothesis or is the BB theory too strong a theory to reasonably counter with an alternative theory.
  5. Apr 9, 2005 #4


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    I'm sure someone more knowledgable can tell you better than I can, but I'll tell you what I know:

    Observational evidence is consistent with BBT... including verification of some of the BBT's predictions.

    Theoretical physics (Loop Quantum Cosmology, at least) suggests that Big Bang + inflation is a natural way for things to evolve... it just popped out of the theory. Incidentally, LQC actually suggests the possibility of a "big bounce" -- the universe collapsed and then bounced back with a big bang.
    Last edited: Apr 9, 2005
  6. Apr 10, 2005 #5
    sd01g; how much reading have you actually done on the subject other than Lerner's book? The reason I ask is sometimes it is easy to be persuaded by an argument that only shows half of a story.

    Sure there are many different theories on the origins of the Universe and not everyone is sold on the BBT, that is why research is still being conducted in this area!

    Maybe you need to put down some of the main concepts of the book so we can comment on it, without having to read it ourselves.
  7. Apr 10, 2005 #6


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    That's a big red-flag. Is that an "electric cosmos" theory? Where gravity is secondary to electric/magnetic forces on the galactic scale? Its a stretch to call such ideas "theories".
  8. Apr 10, 2005 #7
    There are errors in Lerner's book. Edward L. Wright writes about this.

    I think the BBT is well established thanks to:

    1. The high CMB isotropy to better than one part in 100,000. They measure the angular power spectra of the sky using spherical harmonics. In fact, many scientists have tried to devise alternative explanations for the source of this radiation but none have succeeded.

    2. The abundances of light elements. There does exist a universal abundance ratio of helium to hydrogen consistent with current expansion rate and the cosmic background temperature. Also there are no elements heavier than lithium which have a universal abundance ratio. The WMAP satellite should be able to directly measure the ordinary matter density and compare the observed value to the predictions of Big Bang nucleosynthesis.

    3. The universe is accelerating.

    If the BBT is not correct than we should see a theory which will contradict general relativity and so far no one has been able to devise such a theory.

    PS: GR has been found highly successful in a broad number of experiments:

    1. verification of the deflection of light by the sun
    2. the perihelion advance of Mercury
    3. the gravitational redshift of light
    4. the discoveries of quasars
    5. cosmic fireball radiation
    6. pulsars
    7. X-ray sources the might contain black holes
    8. the present interest in the imminent detection of gravitational waves.
    Last edited: Apr 10, 2005
  9. Apr 10, 2005 #8

    why you object to calling electric cosmos theory ? theory means something not yet completelly verified. electric cosmos theory has many plausible concepts .
  10. Apr 10, 2005 #9
    i think he meant this definition of theory:

    A set of statements or principles devised to explain a group of facts or phenomena, especially one that has been repeatedly tested or is widely accepted and can be used to make predictions about natural phenomena.

    not this one:

    An assumption based on limited information or knowledge; a conjecture.
  11. Apr 10, 2005 #10
    yeah, yeah whatever ! :wink:
    what is your view on electric cosmos theory ? for me thanks to reading about it strange anomalies in our solar system looks not so strange afterall.
  12. Apr 10, 2005 #11


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    There's no way to evaluate a probability like that. As for the support for the "Big Bang Theory" (in quotes because the "bang" itself is not supported at all!), I think Starship summed it up rather well.

    However, the support for inflation is really quite scant (the things in starship's post are all post-inflation). The reason it's so popular is that it explains so many of our problems, while fitting nicely with the current understanding of particle physics. It has so many free parameters, however, that it has yet to make any particularly convincing predictions.
  13. Apr 12, 2005 #12
    The idea could be perfect but not enough firmly established experimentally. In fact many have tried to suggest alternative explanations to the 'force' of gravity such as the work function and other stuff. I don't know how reliable this is though.
    Last edited: Apr 12, 2005
  14. Apr 12, 2005 #13


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    The question "what is the probability that BB theory is not correct?" verges on being nonsense, in that, of course, it either is or is not correct. (Unless you talk to those at the fringe of the many world QM theory).

    What you mean to say, of course, is "what is the probability, that scientists will cease to regard BB theory as correct (presumably since you don't state otherwise) over all time in the long run, given what we know today?"

    I think this probability is low, but not zero, and I think that any likely case which could be called a determination that BB theory is incorrect, may come down to a determination of whether another theory is a mere modification of BB theory, or a new theory that replaces it.

    For example, I suspect that the likelihood that the current consensus age of the universe, which is an important part of BB theory in a broader sense, probably approaches 40% or more. On the other hand, the likelihood that scientists will believe anything other than that all matter results from nucleosynthesis of the most elementary particles, which is also a part of BB theory, is vanishingly low, well under 2%. The likelihood that current inflation theory will be replaced, or that the eras of the universe described by big bang theory will be substantially changed, probably is in the 20% range.

    The likelihood that a BB type approach will be replaced by a quasi-steady state model, I would put in the low single digits. But, the likelihood that the consensus will come to be that the big bang was one of many big bangs is a greater "super-universe" beyond the observable universe, based on theoretical considerations that show that the BB would not be a singularity or explain a relationship between the BB and black holes, probably approaches 1 in 3, if not a greater probability.

    Is this based on anything more than informed intuition? No. But, FWIW, you have my guesses. Do I win anything if I'm right?
  15. Apr 12, 2005 #14


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    I object to calling it a theory because calling it a theory implies real research has been done and real evidence exists for it. EC is better characterized as "non-scientific idle speculation". (matt.o's explanation works equally well)

    Anyway, for the OP, ohwilleke's explanation is good - its more complicated than just saying it will or will not be supplanted. It has many parts - some are likely to change and some are not.
  16. Apr 12, 2005 #15
    Maybe he's right. Current cosmologies rest almost entirely on Einstein's theory of gravity as the warping of space-time. Many do not agree with this including Mark McCutcheon.
  17. Apr 12, 2005 #16


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    It's not enough to disagree or wave hands. You have to construct an alternate theory and calculate results that if observed, will falsify GR. Some of our posters, such as Garth, have theories that do this. Others are just blowing smoke.
  18. Apr 12, 2005 #17


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    Any successor to BBT will, among other things, need to explain:
    1] The CMBR, and why it has a perfect black body spectrum
    2] Primordial elememental abundance
    3] Expansion of the universe
    4] Large scale structure
    I've not yet seen such a candidate.
  19. Apr 12, 2005 #18


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    Indeed, many "candidates" live in the loopholes. They attempt to explain a single flaw in an existing theory without reproducing the things that existing theories do explain well.

    Dark matter hasn't been found? Scrap GR altogether!
  20. Apr 13, 2005 #19


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    Scrapping GR all together is one thing. Tweaking it at scales and in situations where there is no experimental verification for it, is another.
  21. Apr 13, 2005 #20
    To rephrase:

    "Current cosmologies rest almost entirely on established physics. Many do not agree with this, including some guy who is not a physicist."

    Same content; more illuminating.
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