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I Big Freeze and Law of convervation of energy

  1. Mar 13, 2017 #1
    (Kurzgesagt- In a Nutshell) says that in the Big Freeze scenario all the matter will decay in the end, how is this possible without breaking the law of convervation of energy?
  2. jcsd
  3. Mar 13, 2017 #2


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    There IS no "conservation of energy" on cosmological scales.
  4. Mar 13, 2017 #3
    By the way, why convervation of energy have an important rol in inflation if there is no convervation of energy in cosmological scales?. https://en.wikipedia.org/wiki/Zero-energy_universe
  5. Mar 13, 2017 #4


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  6. Mar 13, 2017 #5
    phinds or someone else more advanced in the Standard Model may be able to confirm or refute this, but I believe the only thing actually required to be conserved in particle decay is the particle's charges (spin, Baryon/Lepton number, strange, electric, etc.).
  7. Mar 13, 2017 #6
  8. Mar 13, 2017 #7
    The laws of thermodynamics assume a closed system.
  9. Mar 14, 2017 #8


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    It is valid in situations where you can neglect gravity, or in situations where you treat gravitation potential energy as a valid kind of energy. As Sean Carroll stated, there's nothing wrong with thinking of gravitational fields having gravitational energy. The drawback is that it behaves very differently from other forms of energy.

    I think it is advantageous to use the concept of gravitational energy because it makes it clear that you can't make a (cyclic) perpetual motion machine based on gravity. The total non-gravitational energy might be different at different points of the gravitational cycle, but it should return to what it was at a previous cycle.
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