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Please explain to a thick man .

  1. Feb 9, 2006 #1
    Please explain to a thick man.....

    I'm new to this and have a very limited understanding of Physics i.e. High school level.
    My question is (please don't laugh:redface: ); In the centre of the sun there must be a part at which all forces are pushing/pulling in the same direction. Since I would imagine this to be an absolutely colossal force surely the very centre particles/atoms could not move in any direction, which would mean absolute zero, no?
    Can someone explain in laymans terms why this isn't so?
  2. jcsd
  3. Feb 9, 2006 #2


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    As far as I am aware, nobody has actually stuck a thermometer into the middle of the sun, but people generally believe that it is very hot.

    It works something like this:

    Imagine a bunch of tenis players all balls balls into the center of a field. Some of the balls get stuck in the middle because they keep getting hit by balls coming in from the outside. So, although it looks like they're standing still, they're bouncing back and forth very fast. And, in fact, it might be that one or two of the balls does get hit just so that they stop, but the average speed of the balls is still very high.

    Similarly, I expect that atoms are constantly bouncing in and out of the center of the sun.
  4. Feb 10, 2006 #3


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    The atoms in the middle move quite a bit or there would be no fusion.
  5. Feb 10, 2006 #4


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    What do you mean "all forces are pushing/pulling in the same direction."? There is definitely motion going on because, as tony said, nuclear fusion readily takes place within the core of the sun; an action that requires tremendous pressures and temperatures.
  6. Feb 10, 2006 #5
    Thickman, you have the wrong mental image of atomic particles as hard balls squashed together with no space to move. Fundamental atomic particles are incredibly tiny, even though the forces around them may extend for measurable distances, for example there is no measure for the size of an electron even though they have been collided at fantastic energies, It is similar with quarks.

    Neutral atoms and atomic nucleii are composite structures, in which the fundamental particles engage in stable interactions, but that does not prevent them from being crushed much smaller if the conditions require it.

    In the centre of the sun the atoms are crushed into a plasma of free electrons and nucleii with very much less space than a typical atom at room temperature but there is still a good deal more space than a typical nucleus.

    In a neutron star the atoms are crushed to the densities of a nucleus.

    Beyond that is a quark gluon plasma, This is not well investigated yet. but work is going on in heavy ion colliders however observing quark gluon plasma objects in nature is a bit problematic because a neutron star with a mass of 2 or 3 times the sun is only a bit bigger than a black hole of the same mass and so when objects get heavy enough and dense enough to become quark gluon plasmas it looks like they hide themselves behind an event horizon.

    Now beyond that, because the mathematicians dont know any physical processes that could prevent it. it is generally said objects will collapse to a mathematical singularity point line or surface. but these statements as you rightly surmise don't make much physical sense because the physical world needs an absloute minimum of three dimensions so the best thing to say is we don't know, yet.
    Last edited: Feb 10, 2006
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