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Help in a equation I'm going to use for the intel competition

  1. Jul 16, 2010 #1
    1. The problem statement, all variables and given/known data For my project for the intel competition, I'm trying to prove that the expansion of the universe defies conservation of energy. In order to do this i want to simulate the universe as a expanding sphere which has a acceleration that constantly increases. Also in the sphere i want there to be a set amount of particles in it initially, but as the sphere expands the amount of particles in it increases as well. Then using noether's theorem i want to show that this expansion defies conservation of energy. My problem right now is that i don't know how to make a single equation that represent the sphere expanding and the amount of particles in it increasing.

    2. Relevant equations
    X^2+Y^2+Z^2=r*t times cosmological constant

    amount of particles=n*t*cosmological constant

    n= arbitrary number of initial particles

    I still don't know what the modern constant of expansion of the universe is, but I know it's causing a non constant acceleration and I'm sure incorporating it into my equation would be that easy. The problem is I want one equation that describes it all not two separate equations. I know my sphere equation is no where near complete because I'll need to convert it to a Lagrange form so I can compute it in noether's theorem, but I plan on doing that soon.

    3. The attempt at a solution

    All I can think of is setting them up at two equations but then I don't think I'll be able to use noether's theorem to show any conservation laws. Can anyone help me please
  2. jcsd
  3. Jul 17, 2010 #2

    Gib Z

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    Neother's theorem, and all of established cosmology is compatible with Energy conservation and an expanding universe at the same time, so you won't be able to derive a contradicition from any of them.
  4. Jul 17, 2010 #3
    I'll explain further what I'm trying to get at, i believe that the universe obeys conservation of energy. I'm trying to really prove that dark energy, the entity that is causing the expansion of the universe can;t be energy at all because if it was energy then it would defy conservation, because it's being created out of nowhere and the amount of energy in the universe is not constant. I know that dark energy doesn't need to be energy but I'm trying to show that no matter what it is, it can't be energy.
  5. Jul 17, 2010 #4

    Gib Z

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    Well then, once again, Dark Energy being energy is mathematically compatible with all established cosmology, so you won't be able to derive a contradiction with that. The only avenues to prove what you wish to prove is some sort of real life experimental evidence, or create completely new cosmological or physical principles, because the current ones don't rule it out.
  6. Jul 17, 2010 #5
    How can it be mathematically compatible, I'm willing to accept it but it doesn't make any sense physically. As the universe expands it's getting larger and as it's getting larger dark energy is suppose to fill it up. That means energy is being created out of nothingness basically that can't be right.
  7. Jul 17, 2010 #6

    Gib Z

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    Being mathematically compatible with current knowledge does not ensure correctness. A lot of theories of the universe are mathematically compatible with what we know about the universe, but only 1 of them is right, and it's not decided by the mathematics as much as it is by the physics - whether the theory matches observations, predicts new observables that turn out true etc etc. So when a theory passes the initial check point of being at least mathematically compatible with what we already know (in other words, it doesn't derive anything contradictory to established knowledge), then we must either formulate new physical principles (which must eventually be backed up by experimental evidence) or find experimental evidence for the theory directly. A popular example is String Theory, which so far seems mathematically compatible with our current knowledge, but yet has made no testable physical predictions, and so is not established theory yet.

    As for your project, I recommend, as with any research, before trying to uncover new territory on your own, you should read up with the current knowledge of the subject you are studying, as other people may have answered related questions that you will find useful. I assure you, Physicists have already thought of this precise problem and you will find their study very useful.
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