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Falling matter of supernova does work heating the core?

  1. Mar 17, 2014 #1
    Falling matter of supernova does "work" heating the core?

    A supernova core collapses and the rest of the star follows, inner layers arrive first, a shock wave wave forms?

    As outer layers continue to collapse and slow down is there a large radial time rate change in momentum as rapidly inwardly-flowing matter violently slows down?

    Does this time rate change in momentum cause a force on the core comparable to the force given by the gravitational force due to mass of accretted outer layers?

    Do both these forces do work on the core, compress it, and heat it up?

    In the following video there is a simulation of a supernova core with what I guess is shown either violent motion of the matter of the inner core or pressure waves? Can one assume that the surrounding layers of the star not shown interact with this violent sloshing around by the core? See the 30 second mark. Is this violent motion ultimately "driven" by the outer layers?

    Thanks for any help!
    Last edited by a moderator: Sep 25, 2014
  2. jcsd
  3. Mar 19, 2014 #2
    This isn't an easy question to answer. I will take a stab at providing a direction of research to aid you.

    In this example you involve pressure, kinetic energy, temperature and the various forms of matter involved at different layers. Those various forms of matter have different maximum density values.

    So if I were you I would study how you can employ the ideal gas laws into this. Yes the ideal gas laws would only serve as an approximation as the various layers are not in thermal equilibrium. So you will only be able to loosely apply it. It may or may not simplify the various dynamics at work. Obviously the variations between layers would require the gas laws but not the ideal gas laws themself. However the layers in thermal equilibrium could be treated as such with the regions out of equlibrium serving as the boundary.

    Hope that helps, I've seen similar treatments employed in metrics involving accretion disks
    in this article


    you may or may not be able to find the appropriate metric examples in this article. Hopefully you can.

    As far as whether the pressure, temperature or othe factord is doing the work. One textbook I have but cannot post "Thermodynamics of the Universe" can't recall the author and the textbook is currently packed has an applicable statement. Hopefully I have it correct.

    "In thermodynamics the work done by changes of pressure is done by the temperature"

    my memory might be incorrect on that though
    Last edited: Mar 19, 2014
  4. Mar 20, 2014 #3
    You may find this link of interest I located it and other articles by googling "thermodynamics of a supernova core collapse


    looking at some other articles so may add more

    edit this is one of the better articles.. Should answer your questions

    Last edited: Mar 20, 2014
  5. Mar 20, 2014 #4
    Mordred, many thanks for the pointers! Have a good weekend!
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