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The Energy of mass and Gravitational Potantial Energy

  1. Mar 20, 2015 #1
    I know the total energy of universe is zero cause of matter energy (E=mc2) and gravitational potantial energy.
    But If I try to calculate it gets crazy things:
    Lets think universe made up only two particles and their mass call m and equal than

    2mc2=m2G/r
    2c2=mG/r
    r=mG/2c2
    so there must be a certain distance between these objects to make zero energy universe. Am I wrong
     
    Last edited: Mar 20, 2015
  2. jcsd
  3. Mar 21, 2015 #2

    Orodruin

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    Where did you hear this? It is certainly not something that is seen as universally true among physicists. In particular as the definition of energy (and potential energy in particular) is not all that clear in general relativity.
     
  4. Mar 21, 2015 #3
    Everywhere If you search total energy of universe is zero you can look at it.
     
  5. Mar 21, 2015 #4

    Orodruin

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    This is definitely not an accepted fact in physics, please stick to mainstream science and do not quote hypotheses as facts.
     
  6. Mar 21, 2015 #5
    This is a formal approach to the problem. By its order of magnitude this radius is close to the gravitational radius of the mass (m). If the total energy of the Universe is zero, this Universe is in dynamically unstable state. The accelerated Universe, as we know today, can't have zero total energy. Also pay attention that the right side of your equation is relativistically invariant while the right side is not.
     
  7. Mar 21, 2015 #6

    Nugatory

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    This thread started with two mistaken assumptions: First, that it might be an accepted fact that the total energy of the universe is zero; and second, that an equation in which one side is a relativistic invariant and the other is not could possibly make sense.

    As both of these misconceptions have been pointed out, we can close the thread now.
     
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