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Hubbles's law and the Dark Energy Component

  1. Feb 4, 2005 #1
    "RE: Hubble's law is WHAT is driving the
    expansion: the not so recent Findings (last 10-5 yrs)
    is that
    experimentally it looks like there is a dark energy
    At what point does Hubble's Law begin to suggest this
    dark energy component?

    Suzanne Elizabeth Seitz
  2. jcsd
  3. Feb 4, 2005 #2


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    When it was discovered that distant Type 1a supernovae were fainter than otherwise predicted and it was concluded that the universe was accelerating in its expansion rather than contracting.

    Note this conclusion is theory dependent and the observations could have other explanations. DarK Energy is also useful to make up the 'missing mass' of the universe all 73% of it! Another 'epicycle' along the way?
    Last edited: Feb 4, 2005
  4. Feb 4, 2005 #3
    An advisor said:
    "It seems impossible to explain from a fundamental quantum gravity theory.
    Theorists want to have as few 'given's as possible)."

    Do you have any thoughts which way this particular situation with the Hubble's Law may go and is there a point when theory goes into darkness and becomes "ugly"?
  5. Feb 4, 2005 #4


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    If you look at some of my other posts you will see I consider that the standard BB model has already become 'ugly', hence my added reference to 'epicycles'.
    1 The horizon, smoothness and density problems in the unadulterated GR cosmology required Inflation as a 'fix'. Inflation requires the Higgs boson this has not been discovered after nearly 30 years of intensive research.
    2. The standard GR + Inflation model required Dark Matter to explain galactic rotation profiles. DM has not been identified in the laboratory even after again about 30 years of intensive research.
    3. The standard GR + Inflation + DM model required Dark Energy to explain cosmological acceleration and make up the cosmological density to that of critical density for geometric flatness of space-time. Nobody has any idea what DE is although there are as many guesses as papers on the subject! Cosmological constant, quintessence, leaky membranes etc. etc.
  6. Feb 4, 2005 #5
    That should do it!

    Thank you Garth for taking the time to explain the details.
    What jolly fun you scientists must be having.

    Your other post are of great interest and I will look at the conversations on this subject

    I noticed your comment at the bottom of your posts on laughing at one's self.

    I feel that must be the single most truthful comment I have encountered on any public forum!

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