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Spiral arms

  1. Apr 11, 2007 #1

    wolram

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    So far i have found two theorise of how they form, the SSPSF
    shock wave model ,and the Density wave model, or they may
    form by a combination of the two.
    As i am not sure how old these theories are, i wonder if there are
    any new insights on the subject?
     
  2. jcsd
  3. Apr 12, 2007 #2

    Chronos

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    By some schools of thought, spiral arms trace the path taken by primordial gas molecules during the collapse phase. Intervening effects, like shocks imparted by detonations of pop III stars complicate matters when you try to run numerical simulations, but the principle is consistent with observations.
     
  4. Apr 12, 2007 #3

    wolram

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    Trace the path taken by primordial ----,
    what does this mean? i am trying to understand the (as it seems to me) the
    none homogeneous isotropic universe, the universe that has vast voids and
    seemingly fractal mass distribution, if this is not mainstream, i apologise, but
    the formation of a galaxy seems to me a basic starting point.
     
  5. Apr 13, 2007 #4

    Chronos

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    More like an enormous whirlpool of coalescing gas. Stars form from knots in the flow - local overdense regions - but remain bound to the system at large. Centripetal force flattens out the edges of this huge, rotating mass.
     
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