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More on dark energy

  1. Jan 22, 2004 #1


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    ESA's X-ray observatory, XMM-Newton, has returned tantalising new data about the nature of the Universe. In a survey of distant clusters of galaxies, XMM-Newton has found puzzling differences between today's clusters of galaxies and those present in the Universe around seven thousand million years ago. Some scientists claim that this can be interpreted to mean that the 'dark energy' which most astronomers now believe dominates the Universe simply does not exist…
    so could galaxy evolution be hiding the truth about dark
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  3. Jan 22, 2004 #2


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    Wolram, you have pointed us to work by these people before, if I remember.

    Alain Blanchard, Vauclair, Bartlett.

    It is respectable work IMHO and deserves to make people stop and reconsider whether the 73 percent dark energy is not just dark matter instead. The paper that this news item refers to is, I believe,

    http://www.arxiv.org/astro-ph/0311381 [Broken]

    this is a closely reasoned thoroughly referenced 5-page paper by Vauclair, Blanchard, Bartlett and several others.

    If anyone wants they can read it. I dont think they will find anything fringey or flakey---tho thats just one persons impression.

    So IMHO this constitudes a substantive challenge to the "concordance" model with its 73 percent dark energy.

    However is it not true that models get challenged from time to time and this is just part of the sport. Just because Blanchard's side looks like making a strong case doesnt mean the question is settled. There will most likely be a lot more observations and a lot more evidence broght in before one can even guess how it may turn out.

    For my part, in the mean time I will just go on assuming that the concordance model is the best fit and that the apparent contradiction from the XMM-Newton data will eventually be resolved somehow and that dark energy will survive this challenge.
    I will just be a little less confident, having seen this article.

    thanks for finding this.
    Last edited by a moderator: May 1, 2017
  4. Jan 23, 2004 #3


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    i think it makes science a bit more exiting and stimulates
    the old brain cells, for me the less strange thing the
    better, but who knows what the end result will be? its not
    over till the fat lady sings.:smile:
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