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Space and Negative Energy

  1. Sep 20, 2013 #1
    I watched Stephan Hawking's into the universe, I know it's more of a way to make science mainstream than to educate people, but in the episode about is there a god, he said that space was a negative energy and that it equaled the same amount as the energy of the universe. I haven't looked into the math or validity of this statement, because I figured I'd take Hawking's word for it. Perhaps I'm misunderstanding the concept, or Hawking used the statement as more of an analogy so that the viewers of the show could understand the concept. If that's the case then let me know, but if space is negative energy, and adds up to the energy of the universe, then because of inflationary cosmology, shouldn't energy continue to be created as the universe expands, resulting in a continuation of galaxies and matter, so that the universe never really dies, or is all the space from cosmological inflation being converted solely into dark energy? Also on a side note, have the percentages of energy in the universe (4% matter, 25% dark matter, 71% dark energy) remained in the same ratios since the universes inception, or have they changed over the years.
  2. jcsd
  3. Sep 20, 2013 #2
    It seems that you assume that energy is conserved. Energy is NOT conserved in the General Relativity (only in some particular cases). Our expanding universe is not one of these cases.

    The more accurate statement would be that "energy of the whole universe" can't be correctly defined, rather that it is not "conserved". The last statement is valid for the both WHOLE universe and VISIBLE universe (these 2 concepts are incorrectly mixed in popular TV in more than 50% of cases)
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