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-   -   If simulations of the universe (https://www.askmehelpdesk.com/showthread.php?t=775869)

  • Nov 19, 2013, 11:26 PM
    nykkyo
    If simulations of the universe
    Was faithfully rendered before dark energy was postulated doesn't that indicate DE is non-existent, or at least the outward forces applied to the masses in a rotating universe?
  • Nov 20, 2013, 02:23 AM
    joypulv
    'Faithfully rendered simulation' sounds meaningless to me. Please explain?
  • Nov 20, 2013, 02:38 AM
    nykkyo
    Computer simulationsof how the universe evolved from the BB, gravity.black holes and postulating dark matter.
  • Nov 20, 2013, 02:43 AM
    nykkyo
    Quote:

    Originally Posted by nykkyo View Post
    Computer simulationsof how the universe evolved from the BB, gravity.black holes and postulating dark matter.

    Compter simulations of how the univrse evolved with gravity and postulated dark matter. Faithfully, I mean the simulations look like today.
  • Nov 20, 2013, 02:53 AM
    Tuttyd
    I don't think we can talk about a rotating universe in any meaningful way.
  • Nov 20, 2013, 03:01 AM
    nykkyo
    Quote:

    Originally Posted by Tuttyd View Post
    I don't think we can talk about a rotating universe in any meaningful way.

    Wel... the only way we can detect rotation is the extra outward force on the expanding volume, like a ball on a large merry-go-round! Any other way would be to get ouside the universe.
  • Nov 20, 2013, 10:04 AM
    ebaines
    Let me see if I understand your question nykko:

    "If simulations of the universe was faithfully rendered before dark energy was postulated doesn't that indicate DE is non-existent..." I assume what you mean is "If models of the early universe fit the data before dark energy was postulated then DE is non-existent" But that's exactly why dark energy is postulated - because without it the models do not agree with the data. So no - before dark energy was postulated such "simulations" did not faithfully render the universe.

    " , or at least the outward forces applied to the masses in a rotating universe?"

    I assume you're speaking of centripedal acceleration on parts of a rotating system, such that the resulting inertial forces cause bodies to move outward from the center of rotation. That concept doesn't apply, for several reasons. First you need some mechanism to cause the bodies to rotate about a center - what would that be? Second, there is no center of the universe, and no center of rotation, and hence no centripedal acceleration on the scale of the universe.

    From this and other posts it seems you think of the universe as if it was a 3-dimensional expanding balloon inside a larger 3-dimensional room. But the universe is not like that - it has no center, and there is no larger space that it is expanding into. So analogies to solid mechanical devices like a merry-go-round don't apply.
  • Nov 20, 2013, 05:25 PM
    nykkyo
    Quote:

    Originally Posted by ebaines View Post
    Let me see if I understand your question nykko:

    "If simulations of the universe was faithfully rendered before dark energy was postulated doesn't that indicate DE is non-existent..." I assume what you mean is "If models of the early universe fit the data before dark energy was postulated then DE is non-existent" But that's exactly why dark energy is postulated - because without it the models do not agree with the data. So no - before dark energy was postulated such "simulations" did not faithfully render the universe.

    " , or at least the outward forces applied to the masses in a rotating universe?"

    I assume you're speaking of centripedal acceleration on parts of a rotating system, such that the resulting inertial forces cause bodies to move outward from the center of rotation. That concept doesn't apply, for several reasons. First you need some mechanism to cause the bodies to rotate about a center - what would that be? Second, there is no center of the universe, and no center of rotation, and hence no centripedal acceleration on the scale of the universe.

    From this and other posts it seems you think of the universe as if it was a 3-dimensional expanding balloon inside a larger 3-dimensional room. But the universe is not like that - it has no center, and there is no larger space that it is expanding into. So analogies to solid mechanical devices like a merry-go-round don't apply.

    Spacetime is a mathematical contrivance for the prrpose a define ravity as tge restoring force of a displaced quanta of a continumm (continuum mechanics- by asserting time,mass and length as variantats). FEE's stress and metric tensors define spacetime as an elastic medium, where gravity is the force of the continuum trying to restore equilibrium. In the continuum perspetive, the force from the outside to the CM (rlated to volume during the fusion stage); but when fusion ceases and a mass begins to shrink, the force is perceived as related to denesity). As the radius of the mass decreases the restorinh force decreases. In this scenario the force toward the CM is not enough to collapse mass to a singularity (since neucleons cannot ocupy the same place at the same time-Pauli exclusion). This presents gravity as an ambiguous concept between fusio and black holes. How is it that the Earth can orbit the Sun without impedance and at the same time be held in orit by mechanically interact to produce a force to the CM?

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