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Thoughts on gravity and space time

  1. Nov 12, 2009 #1
    If the Mass of an object is said to warp space time, could it be said that "gravity" is really an object trying to come to equilibrium within the warped space time, i bit like a cork in water. the reason we feel force at the earths surface is that the earth is already at equilibrium which prevents us from reaching the point of equilibrium.

    This points to the fact that weightlessness is just the state of equilibrium within space time.

    until these thoughts i used to wonder if the effects of "Gravity" would change the deeper you went into the earth. but now the effects of warped space time must permeate through all mass a bit like the C of G of an aircraft, the warping must reach end at the centre of the mass!

    as this is my first time is this just stating the obvious or shall i continue
     
  2. jcsd
  3. Nov 12, 2009 #2

    A.T.

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  4. Nov 26, 2009 #3
    sorry it took so long but been away. Not quite sure how to understand your link but that would be my failing. Yes you are right i did miss explain myself i was trying to suggest that Gravity is not a force of attraction between 2 objects which is how most explanations show it. my idea is that Gravity is really a pressure felt by an object which is trying to come into equilibrium within warped space time. a bit like a cork in water however this is almost a 2D explanation.
     
  5. Nov 26, 2009 #4

    A.T.

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    In GR objects which are in equilibrium (free falling) simply advance straight ahead within warped space time. Just like that yellow ball in the linked animation.
     
  6. Nov 26, 2009 #5
    This would be correct if this object was an atom, you have to understand anything that has matter/energy has a coresponding mass. . . . I think this is correct because something that is hot weighs slightly more than the same object at a cooler temperature hence energy has in some form mass, and vice versa(E=mc2). . . If you take a sphere, all the atoms in this sphere are bending spacetime individually, however the overall force makes them all fall towards the center. And since when you reach the center of the object like if there was a whole in the center of a sphere, yes eventually the effect of gravity on you becomes less and less till you reach the center where there will be no net force, But you have not reached equilibrium. Its like a game of tug of war, when the two teams are evenly matched and the flag doesnt move, its not at equilibrium because the two teams are still exerting forces on the rope.
     
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