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End of cosmology

  1. Mar 21, 2008 #1
    The other day I read a rencent article in Scientific American entitled "The End of Cosmology." I have a simple question that I hope someone can clarify for me.

    Let me first give a brief summary and my understanding of the article. In every direction the universe is expanding, and this expansion is accelerating.
    Accelerating so much so that at some point, galaxies will be flying away from us at the speed of light and beyond. Therefore, we will not be able to see them. Large portions of the universe will disappear. The point of the article is that we are lucky enough to exist in the only epoch where we can observe and expanding universe and find evidence of a big bang.

    Anyway, on to my question. I thought that the theory of Special Relativity tells us that nothing can travel faster than the speed of light. Am I missing something, or do the observations mentioned in the article contradict this theory?

    Oh, here, I found the article on the web. Here is he link.
    http://www.sciam.com/article.cfm?id=the-end-of-cosmology
     
  2. jcsd
  3. Mar 21, 2008 #2

    cristo

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    Try having a read of this paper: http://www.astro.princeton.edu/~aes/AST105/Readings/misconceptionsBigBang.pdf. I think this is good as a first explanation but, if you have any questions once you've read this, feel free to ask!

    As an aside, whilst googling I found a more technical version of this paper: http://www.mso.anu.edu.au/~charley/papers/DavisLineweaver04.pdf. Just thought I'd share with whomever may be reading this (although I guess marcus has already pointed this out a long time ago!)
     
    Last edited: Mar 21, 2008
  4. Mar 21, 2008 #3
    Thanks for the links cristo
     
  5. Apr 8, 2008 #4
    It would be interesting to see 30 years from now if this article about "expanding space" still makes any scientific sense or that those who are straight lipped about it now refuse to bring it up out of sheer embarrassment.
     
  6. Apr 8, 2008 #5
    You don't like the idea of "expanding space"? What exactly do you take issue with?
     
  7. Apr 8, 2008 #6
    1. Taking properties of a coordinate chart of spacetime for a physical reality.
    2. Plugging observational data into metrics and then claiming it is valid beause it is a solution to the Einstein field equations.
     
  8. Apr 8, 2008 #7

    Wallace

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    Who exactly are you accusing of doing the above??
     
  9. Apr 8, 2008 #8
    Well, le't say that if nobody does that I am delighted. :smile:
     
  10. Apr 8, 2008 #9

    Wallace

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    Can you be more explicit about your objections? You have raised them repeatedly without making it clear what you are referring to. You have ridiculed a very good piece of pop-sci writing that clears up a lot of the confusion surrounding terms such as 'the expansion of space'. I think if you read it you might find that it is much closer to your opinion on this than you think. You seem to be repeatedly attacking a strawman version of the way cosmologists use relativity. If I'm mistaken please enlighten me (and everyone else).
     
  11. Apr 8, 2008 #10

    Chronos

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    Plugging observational evidence into a metric and discovering it yields results in agreement with theory sounds like good science to me.
     
  12. Apr 9, 2008 #11
    Ok, I am totally wrong, all cosmologist follow GR to the letter and never mistake coordinate charts from physical reality, and the introductions of dark energy and dark matter are brilliant gems that transforms everything into a beautiful and consistent theory.
     
    Last edited: Apr 9, 2008
  13. Apr 9, 2008 #12
    It does not agree with theory, only after plugging in the right amounts of dark energy and dark matter, and then it holds, of course only until the next discovery introduces another round of adjustments.
     
    Last edited: Apr 9, 2008
  14. Apr 9, 2008 #13
    Hi Grmnsplex,

    Suffice it to say that nothing can travel faster than the speed of light THROUGH space, but space itself can expand far faster than the speed of light. For example, 3 seconds or so after the Big Bang, space was expanding at a rate many times in excesss of the speed of light.
     
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