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3 comments

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• 1
  socratus Aug 9, 2012 9:44 PM

  What is dark matter?

  And in less than 10 seconds, I explain what dark matter is:
  =.
  Dark matter is consist of dark particles.
  The dark particles are Dirac virtual particles.

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• 2
  dchakalov Aug 9, 2012 11:48 PM

  The dark (non-baryonic) dancing elephant

  The "logical" reasoning offered by Luke Davies is like this: 'I cannot see "dark matter", but I know gravity exists, therefore "dark matter" must exist as well.'
  
  Notice the non sequitur: gravity exists, ergo there must be "non-baryonic dark matter".
  
  Suppose you go in a china shop and see all (baryonic) porcelain vases and cups arranged in the air, in a perfectly stable configuration, and wonder what the heck has designed and supported such an amazing configuration of fragile stuff. Then physicists [1] tell you that it is all due to an invisible dark dancing elephant, which is roughly four times larger than all vases and cups combined.
  
  If you are a bit reluctant to swallow such 'dark (non-baryonic) dancing elephant', check out a simple, yet non-trivial, explanation here.
  
  D. Chakalov
  -----------
  
  [1] Jörg P. Dietrich et al., Nature 487, 202–204 (12 July 2012)

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• 3
  John Duffield Aug 15, 2012 11:21 AM United Kingdom

  I thought it was a good little presentation. Luke ended up by saying "we can't say much else" which was bang-on. I'm glad he didn't get sucked into the presumption that dark matter must be comprised of particles such as WIMPs. Because as I am fond of saying: space is dark, it has its vacuum energy, that energy has a mass equivalence, and there's a lot of it about!

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