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Siobhan Morgan's cosmology calculator has a new url

  1. Dec 6, 2006 #1

    marcus

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    her new url is
    http://faculty.cns.uni.edu/~morgan/ajjar/Cosmology/cosmos.html

    her cosmology calculator is a handy resource especially since Ned Wright modified his cosmology calculator earlier this year----July sometime.

    Now, with Wright's, you can't input a redshift z.
    You have to input a "light travel time" and then it tells you the z.

    this is not intuitive to me because what one OBSERVES is a redshift z and then one wants to know things like how far away and what light travel time was etc.
    ============

    with Siobhan you have to type in parameters
    0.27 for "omega" (abbr. omega sub matter, the matter component)
    0.73 for "lambda" (cosmological constant component)
    71 for H

    Ned Wright gives you these values of the parameters as a default.

    If anyone has a link for some other alternative cosmology calculator, please post. I think Hellfire programmed his own but i don't have a link.
     
    Last edited: Dec 6, 2006
  2. jcsd
  3. Dec 6, 2006 #2

    hellfire

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    You can find it here. Some parts are still work in progress.
     
    Last edited: Dec 6, 2006
  4. Dec 7, 2006 #3

    Chronos

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    Thanks for the link, marcus. I actually use this thing on occasion [too much time on my hands]. Also, thanks to hellfire for the link to his calculator. That one is better suited to my usually evil purposes [humor checking papers that make odd claims].
     
  5. Dec 7, 2006 #4

    marcus

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    Hi Hellfire and Chronos,

    thanks for the link, and Chronos thank YOU for the kind word in that other thread and for your "write-in" vote.

    I made a minor mistake in the original post about Ned Wright's calculator. He has several versions now.

    There is still the familiar old one that you enter z and it gives you travel time etc.

    And there is the new version that I happened to see and took for the only one available, where you enter the travel time and it gives you z and other stuff.

    And finally there is an "ADVANCED" version where you put in sophisticated parameters like (not merely the cosmological constant) but the EQUATION OF STATE of the alleged dark energy or quintessence, and other things. It could turn out to be a lot of fun to play around with.
     
  6. Dec 17, 2006 #5

    Chronos

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    marcus, that is dangerous candy to be passing out. No telling what I might do with that kind of ammunition. You do an excellent job giving us heads ups and explaining the significance of papers in 'beyond the standard model', which I think is extremely important and fascinating. I think that topic deserves a category of its own. That is what draws serious scientists to PF. i Have seen more world class scientists chime in here than any other forum on PF. And that is largely due to your efforts to draw high level discussion to these subjects. I mostly watch in awe. I have limited understanding of such issues, but have learned more than I ever imagined possible here. In short, I greatly appreciate your contributions.
     
  7. Dec 17, 2006 #6

    marcus

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    :bugeye:
    :biggrin:

    it's a twoway street

    BTW didn't selfAdjoint say he would be away for the holidays?
    feels like a skeleton crew at the moment

    ==============
    PS
    I see the 2006 Guru placards are up now!
    Congratulations to hellfire on the handsome badge of honor.
     
    Last edited: Dec 17, 2006
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