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Gravity, from a different point of view

  1. Jun 13, 2004 #1
    Gravity has always been thought of as an attractive force between two masses. Is there any reason for this view? just because the net result of gravity is that two masses attract each other, is this really all that is going on.
    About an hour ago an idea hit me, and thinking about it since then it seems to make more and more sense. could it not be that "gravity" as we see it is caused not by exchange of particles or a disturbance in space time but by a mass getting in the way of another force. There may be a constant force on all objects from all directions, which when out in space and free from any gravitational effects would cancel out. when this force (what ever it may be, a flux of virtual particles in my opinion) passes through a mass of atoms it loses energy. if this disturbed force is now observed out in space away from the mass which it passed through it will be a lower magnitude than the force from all other directions, the net result of this is that any object in this region of space will experiance a force toward the mass which disturbed the force.
    This may seem a needlessly complicated way to explain a simple effect but I would be interested to hear peoples opinions on it. you never know this might lead to a "better" theory of gravity, more in line with the other 3 forces, but i doubt it.
  2. jcsd
  3. Jun 13, 2004 #2


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    Staff: Mentor

    That's called "pushing gravity" and its not a new idea, but the main problem is there is no evidence for it.
  4. Jun 13, 2004 #3
    I had a similar idea and posted it once. Got this reply:
    Here's what physicist Richard Feynman had to say about
    a similar theory:

    Many mechanisms for gravitation have been suggested. It is interesting to
    consider one of these, which many people have thought of from time to time. At
    first, one is quite excited and happy when he "discovers" it, but he soon finds
    that it is not correct. It was first discovered about 1750. Suppose there were
    many particles [bullets] moving in space at a very high speed in all directions
    and being only slightly absorbed in going through matter. When they are
    absorbed, they give an impulse to the earth. However, since there are as many
    going one way as another, the impulses all balance. But when the sun is nearby,
    the particles coming towards the earth through the sun are partially absorbed,
    so fewer of them are coming from the sun than are coming from the other side.
    Therefore, the earth feels a net impulse toward the sun and it does not take one
    long to see that it is inversely as the square of the distance... What is wrong
    with this machinery? It involves some new consequences which are not true. This
    particular idea has the following trouble: the earth, in moving around the sun,
    would impinge on more particles which are coming from its forward side than from
    the hind side (when you run in the rain, the rain in your face is stronger than
    on the back of your head!) Therefore, there would be more impulse given the
    earth from the front, and the earth would feel a resistance to motion and would
    be slowing up in its orbit... so this mechanism does not work. No machinery has
    ever been invented that "explains" gravity without also predicting some other
    phenomenon that does not exist.
  5. Jun 13, 2004 #4
    What if the distribution of particles is Lorentz-invariant ?
    The the argument of more impact at the front of earth
    does not imply. Vacuum fluctuations do have indeed
    such a distribution (I remember an old Sci.Am. article
    about this.) Gravity would then be caused by matter
    influencing the distribution of vacuum fluctuations.
    As far as I know, Sakharov had such an idea many years ago.

    By the way, check out http://yolanda3.dynalias.org/wbpage/wpage.html [Broken] !
    Last edited by a moderator: May 1, 2017
  6. Jun 13, 2004 #5
    I don't know much about vacuum fluctuations. How does matter influence them? Is it inversely proportional to square of distance?
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