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Matter/energy ratio

  1. Apr 28, 2005 #1
    Hello, I'm new here. This homework question is really stumping me, I can't seem to find the answer anywhere.

    The question reads:

    In the critical universe now proposed, the ratio of matter/energy is about:
    A) 10/90
    B) 50/50
    C) 35/65
    D) unknown

    any help on this would be greatly appreciated, thanks!
  2. jcsd
  3. Apr 28, 2005 #2


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    This is a strange question. What do they mean by "energy"? Do they mean dark energy? If so, C is the closest answer. If they mean radiation energy, then none of the answers are right, so that can't be it. Technically, mass is a form of energy, so I would say that the person who came up with this question needs a physics refresher.
  4. Apr 28, 2005 #3
    yeah, I originally put C as well, but i realized how confusing this question is and just figured I'd confirm with some of you guys...thanks a lot for your help though....I'll assume it's C but I'll still wait for more replies
  5. Apr 28, 2005 #4


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    Welcome to these Forums sp3685!!
    Well, it depends on what you are prepared to allow as ‘matter’ and ‘energy’ as SpaceTiger said, he beat me to it!

    The general consensus is that the detailed observational verification of this ‘Lambda’CDM model is the mass of the universe consists of 23 per cent dark matter, 73 per cent dark energy and just 4 per cent ordinary matter.

    So if dark energy and dark matter are allowed the answer is 27::73 – none of your ‘tick boxes’!
    But, as we have no idea what DE and DM are, or even if they really exist, perhaps the answer (D) would be most accurate!

    Last edited: Apr 28, 2005
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