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Gravity, Pressure and forces - a thought experiment

  1. May 1, 2012 #1

    I just wanted to get some peoples opinions on a thought experiment I've had. If you can provide references to your input this would be helpful. If you only want to pass comment then keep that to yourself. I'm really looking for constructive feedback in terms of science, learning and education.

    So her goes - let me know what's right and wrong and correct the thought experiment where necessary:

    If pressure is the effect of a force applied to a surface, then we can say that the pressure felt on one atom(generalised) is the force applied to it from another atom.

    Since atoms have mass and the gravitation between atoms is proportional to their mass, we can calculate the gravitation force that is to be felt as pressure between two atoms.

    If we visualise an empty universe with only 2 atoms separated by any distance, the two atoms would be drawn together through gravitation.

    Since F = MA, we can say that the atoms will collide with a given amount of force with force being higher the greater the initial distance.

    Depending on the type of atoms and their kinetic energy, the two atoms will either bounce off each other in an endless loop, form a chemical bond or fuse together to form a new element.

    If we visualise an empty universe with only 10 atoms, constrained inside a straight tube as wide as one atom and as long as 10 atoms, the force felt by the two outermost atoms would be the equivalent to the force it applies to the atom next to it, plus the lesser force felt by each of the other atoms proportional to their distance. Thus the centre most atoms would feel the greatest force/pressure as a result of their resulting mass/gravitation.

    If we visualise an empty universe with a sphere of 1000 atoms, we can say that the atoms at the surface of the sphere feel the lowest force/pressure. We can also say that the force/pressure felt by the centre most atoms would be the highest.

    If we then apply a constant angular force to the sphere of atoms to effectuate a spin, each atom will begin to have potential energy (F= MA).

    As spin increases, the Angular force of the outer atoms will be greatest and the angular force will gradually cause the atoms to draw away from the centre of the sphere.

    As the outermost and fastest moving atoms draw away from the centre of the sphere, those atoms will have a lesser gravitation effect on the other atoms as distance decreases the gravimetric force.

    As we move away from the fastest moving atoms on the spheres' surface towards the slowest moving atoms on the spheres' surface, these slower atoms will feel less gravimetric force than before as the faster moving atoms are now further away.

    Because the outer most atoms have a greater angular momentum and effectively a momentum force away from the centre, the closer to the centre of the sphere, the greater the net 'pull' away from the centre will be as a result of the sum gravimetric force. As a result, a void will form in the centre of the sphere.

    A shell forms as spin increases, with the shell thickness being proportional to the mass of atoms and the angular momentum.

    If spin increases further, the sphere will begin to flatten as a result of centrifugal forces.

    If spin increases yet further, the flattened sphere will form a hollow toroid.

    If spin is increased even further, the toroid hollow diameter will narrow and the diameter of the toroid will increase.

    And that's it! I hope you enjoyed and please, constructive input is welcome. All others can keep to themselves.
  2. jcsd
  3. May 2, 2012 #2


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    Hmm.. I counted 16 statements with errors in at least 10. I'll just deal with the first one.
    Pressure is not force. Pressure is force per unit area. Pressure on an atom is therefore meaningless.
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