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Alternative to the big bang [new scientist]

  1. Sep 10, 2007 #1

    matthyaouw

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  2. jcsd
  3. Sep 10, 2007 #2

    marcus

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    I'm not sure Germani's "heresy" is all that interesting in light of Reuter's explanation of inflation with graceful exit in a way that does not require an inflaton field.
    Could be that Germani is just tilting at last years windmills.

    However the New Scientist "pay-per-view" is no big obstacle. Anyone who is interested can read Germani's papers about his "SLINGSHOT COSMOLOGY" for free on arxiv

    http://arxiv.org/abs/0706.0023
    The Cosmological Slingshot Scenario: Myths and Facts
    Authors: Cristiano Germani (SISSA and INFN), Nicolas Grandi (La Plata, Inst. Natl. Phys.), Alex Kehagias (Natl. Tech. U., Athens)
    (Submitted on 1 Jun 2007 (v1), last revised 4 Jun 2007 (this version, v2))

    Abstract: In this paper we clarify two important issues regarding the Cosmological Slingshot Scenario, namely the choice of frame and the creation of primordial fluctuations. In particular, we show that the Einstein frame represents a non-trivial bouncing cosmology. Regarding the calculation of the primordial perturbations, we identify their vacuum state and elucidate their evolution from the quantum to the classical regimes. Finally, we calculate the exact power spectrum of primordial perturbations showing its compatibility with current data.

    Comments: 14 pages, 1 figures;

    http://arxiv.org/abs/0706.0025
    Matching WMAP 3-yrs results with the Cosmological Slingshot Primordial Spectrum
    Authors: Cristiano Germani (SISSA), Michele Liguori (DAMTP)
    (Submitted on 1 Jun 2007)

    Abstract: We show that the Slingshot primordial spectrum of scalar perturbations agrees, with high level of accuracy, with the WMAP three-years data. In its general form, the Slingshot power spectrum naturally contains an infrared cut-off. If this infrared cut-off is outside the WMAP window, the agreement with data can be found by fixing only two parameters, the spectral index and the normalization of the power spectrum, at any fixed high multipole (l>10). Conversely, if the infrared cut-off is within the WMAP window, the power spectrum of temperature fluctuations can be slightly bluer at low multipoles (l<10).

    Comments: 5 pages, 4 figures
    ============================

    I havent looked at these so I cant either recommend or DIScommend them. May turn out to be of interest---just can't tell.

    thanks to Matt for calling attention to them.
     
  4. Sep 11, 2007 #3

    Chronos

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    'New Scientist' weaves fact with fantasy too often for my comfort level. I find myself spending more time validating their 'facts' than reading the articles. It's a constructive, albeit frustrating exercise. It's sort of like the 'Jerry Springer' of pop science.
     
  5. Sep 11, 2007 #4

    Wallace

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    Ick, I read the article up until this gem:

    "We don't have any fundamental physical explanation for how or why it occurred," he says. "Yet cosmologists today accept it as though it is a religion."

    I can't even begin to describe the confusion of ideas that leads to this kind of view!
     
  6. Sep 11, 2007 #5

    marcus

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    I gather you read a bit of the New Scientist article. I didn't look at it because it tends to work better for me if I totally avoid reading NewSci as long as I can find the REAL articles on arxiv.org or in some other more solid journal.

    thanks for posting your reaction. Maybe we can just ignore Germani's speculative stuff?
    Has anyone looked at Germani's actual papers about Slingshot Cosmology that are on arxiv?
     
  7. Sep 14, 2007 #6
    hey man don't worry Big Bang is the true model of the beginning of the universe. I believe that the creator of this whole universe which i call"Discoveror of Nature" had must follow the Big Bangmodel to create this elegant, beautiful,unimaginably complex despite of its beauty cosmos. Big Bang is as sure as Earth goes round the sun.
     
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