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SciAm Lineweaver cosmology article, March issue

  1. Mar 6, 2005 #1

    marcus

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  2. jcsd
  3. Mar 6, 2005 #2
    that's where I got the information for the test I wrote in here a couple of days ago.
     
  4. Mar 6, 2005 #3

    marcus

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    Good going tribdog!

    The gist of the article is contained in a few visual "sidebars" which ask a question, give a "popular misconception" wrong answer, and then give the right answer:

    http://www.sciam.com/media/inline/0009F0CA-C523-1213-852383414B7F0147_p39.gif
    What kind of explosion was the big bang?

    http://www.sciam.com/media/inline/0009F0CA-C523-1213-852383414B7F0147_p40.gif
    Can galaxies recede faster than light?

    http://www.sciam.com/media/inline/0009F0CA-C523-1213-852383414B7F0147_p42.gif
    Can we see galaxies receding faster than light?

    http://www.sciam.com/media/inline/0009F0CA-C523-1213-852383414B7F0147_p43.gif
    Why is there a cosmic redshift?

    http://www.sciam.com/media/inline/0009F0CA-C523-1213-852383414B7F0147_p44.gif
    How large is the observable universe?

    http://www.sciam.com/media/inline/0009F0CA-C523-1213-852383414B7F0147_p45.gif
    Do objects inside the universe expand, too?
     
  5. Mar 6, 2005 #4

    Chronos

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    Surely you don't expect all those 'mainstream' answers to be correct.
     
  6. Mar 6, 2005 #5

    marcus

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    there are 6 mainstream answers here. Only #5 is quantitative: "how large".
    Even #5 is essentially qualitative, saying that the radius of the observable is substantially larger than the estimated age expressed in lightyears (14 billion LY)

    I consider these 6 qualitative propositions to be reasonable and not especially model-specific. I suspect that any new model which could succeed in replacing the current consensus model is likely to have at least these six qualitative features..

    And so I hope anyone here who disagrees will say explicitly which of these features he expects not to hold in whatever replacement consensus model when such a model has been tested and has prevailed

    http://www.sciam.com/media/inline/0009F0CA-C523-1213-852383414B7F0147_p39.gif
    What kind of explosion was the big bang? (an expansion of space, not an explosion localized in space)

    http://www.sciam.com/media/inline/0009F0CA-C523-1213-852383414B7F0147_p40.gif
    Can galaxies recede faster than light? (yes)

    http://www.sciam.com/media/inline/0009F0CA-C523-1213-852383414B7F0147_p42.gif
    Can we see galaxies receding faster than light? (yes)

    http://www.sciam.com/media/inline/0009F0CA-C523-1213-852383414B7F0147_p43.gif
    Why is there a cosmic redshift? (stretching of light in transit)

    http://www.sciam.com/media/inline/0009F0CA-C523-1213-852383414B7F0147_p44.gif
    How large is the observable universe? (substantially larger than 14 billion LY, i.e. than the estimated age expressed in lightyears)

    http://www.sciam.com/media/inline/0009F0CA-C523-1213-852383414B7F0147_p45.gif
    Do objects inside the universe expand, too? (in a qualitative sense, coherent objects like galaxies or the things in them are not at present expanding)
     
  7. Mar 7, 2005 #6

    Chronos

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    One of my usual wisecrack answers. I would argue Q5 is not really relevant. I'm thoroughly comfortable with the BB model, as you probably suspect.
     
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