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Stephen Hawking and Zero Energy

  1. Jan 28, 2015 #1
    I've heard famous physicists like Stephen Hawking promote the idea that the conflict between the laws of thermodynamics and the beginning of the universe can be avoided if there is the same amount of anti-matter as there is matter, making the total energy level zero. I understand, that makes sense. However, something does not feel right, shouldn't it take energy to start that?
  2. jcsd
  3. Jan 28, 2015 #2


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    Our current model of cosmology is The Big Bang Theory and it has nothing to say about how the universe started, it just talks about how the universe evolved starting about one Plank Time after it did what ever it did at t=0 (the singularity). Thus I think it likely that what you are seeing is discussions about that evolution and how it could end up with the universe that we have today. That is, what were the conditions at one Plank Time?
  4. Jan 28, 2015 #3
    Hawking states that he can make the origin of the universe fit in with the laws of thermodynamics by eliminating total energy in the universe to zero by anti matter. However, this does nothing but push the question. How could the process that made matter and anti matter begin without energy? He might have eliminated conflicts for matter, but he only set up new conflicts for the energy that caused his solution to come into existence.
  5. Jan 28, 2015 #4


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    So far, it's always turtles all the way down.
  6. Jan 28, 2015 #5


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    That's interesting. As far as I understood it, anti-matter doesn't have negative energy or mass, but positive. After all, annihilation doesn't eliminate energy, it produces it.

    This will probably always be the case. We might be able to get around it by saying that the universe has always existed in some form or another, but this just pushes the question to "why has the universe always existed?".
  7. Feb 6, 2015 #6
    Negative mass (which isn't antimatter, as you mentioned) would sure be nice for time travel and FTL travel, heh. Only issue with that is, is that if you're saying; "well, it's okay because total energy = 0", then what determines how much mass and negative mass to create?

    In any case, I really popped in for the last paragraph. I'd think when it comes to chasing the causal chain back to the first link as to why the universe exists at all, we'll either chase it forever, or find at some point that it's recursive.
  8. Feb 8, 2015 #7
    I never asked 'why' the universe exists, I said that Hawking tried to align the creation of energy with the laws of thermodynamics, in that, he achieved nothing but push the question back, where did the initial energy come from, needed to start the process of energy / negative energy creation that would ultimately avoid the laws.
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