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If energy cannot be created or destroyed, what is the universe?

  1. Jan 3, 2014 #1
    I really hope this isn't another stupid question but I think it's a valid question so i'll ask it.

    If the conservation of energy law states that energy cannot be created or destroyed, then why did it come into existence when the big bang happened? Could we not assume that the energy that created the big bang is also the universe itself? So basically if the 1st law of thermodynamics is true, does that not state that energy has always existed in one form or another?

    So if that second statement is true, we can say that the universe has always existed in one form or another and thus was never created, because it always existed, and if it always existed, that supports the 1st law of thermodyamics?

  2. jcsd
  3. Jan 3, 2014 #2
  4. Jan 3, 2014 #3


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    We do not know how the universe came into existence. The Big Bang Theory does NOT deal with the origin of the universe. It simply states that the universe was once in a very hot, very dense state and expanded and cooled from there over time, eventually leading to the universe as we see it today. So your question cannot be answered with any certainty.
  5. Jan 4, 2014 #4


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    Hope blooms eternal. We still hold hope some questions will be clarified by CMB polarization measurements, LIGO, JWST and a number of other efforts still underway. We have made remarkable progress over the past decade.
  6. Jan 4, 2014 #5


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    Conservation of energy doesn't apply in a curved space-time in general. See here for an in-depth discussion:
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