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Are forces two dimensional?

  1. Jul 30, 2011 #1
    I think of Particles, Electrons, Protons, Up Quarks, Strange Quarks, etc. They all have mass, and therefore have volume... So they are 3D right?

    But when I think of forces and waves, light waves, sound waves, photons, gravity (gravitons), they are essentially mass-less and therefore have no depth... which means they are 2D right? They may travel through the 3 dimension.... but they are 2D and a planar? Correct?

    Is there any way of proving this?
  2. jcsd
  3. Jul 30, 2011 #2
    Why would masslessness imply two dimensons? That just makes no sense.
  4. Jul 30, 2011 #3


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    As far as we know, fundamental particles are zero-dimensional. For example, an electron has mass, but no volume. (This is based on present, well tested theories of physics. The answer would be different, for example, in string theory.) Although they have zero intrinsic size, they are also waves. If you talk about the spatial extent of the wave, then they are all three-dimensional objects.

    You need to distinguish between forces (like a frictional force) and particles that carry forces (bosons). The fundamental bosons are just like the fundamental fermions in this respect. As far as we know, they have zero intrinsic size. In terms of the spatial extent of the wave, they are three-dimensional.
  5. Jul 30, 2011 #4
    How does that answer my question?
  6. Jul 30, 2011 #5
    Well, if the world is three dimensional, then it would seem that everything in it can be considered, in some sense, three dimensional. Force is typically thought of as an influence that causes some change in the motion of a ponderable body. It's defined as the product of the mass of an object and its acceleration. Ultimately, everything's defined in terms of relative positioning in some coordinate space. So, it would seem that force in a 3D world can be rightly considered to be a 3D phenomenon. The difficulty with, say, gravitational behavior, or the behavior of light is that you're dealing with disturbances in unknown media, or media of unknown structure. Anyway, unless what is typically called empty space is really empty, then force, insofar as it involves the interaction of, assumed, 3D phenomena, is 3D.
  7. Jul 30, 2011 #6
    Of course a force needs three dimensions to fully describe (accomodate?) it since the cross product of a force and a displacement points into the third dimension.

    I assume further to this any 'fundamental' particle that was later proved to possess a finer structure would occupy volume to accomodate the components of that structure?
  8. Jul 30, 2011 #7
    But does 1 part of a force ever exist in 2 places at 1 time of our 3D universe, or does it just move to another place as time passes... so for the time being it appears 3D but if you stopped time the force would just be a 2D substance moving along our 3D universe?
  9. Jul 30, 2011 #8


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    It doesn't answer the question in your #2, which was addressed to the OP. The OP's question doesn't make sense to me, either.

    Right. That's what happened, for example, with the proton and the neutron.

    Could you tell us something about your background in physics? The way you're using words here doesn't sound like the way those words are used in physics.

    A force in the Newtonian sense isn't a substance. Again, it would help if you could tell us about your background.
  10. Jul 30, 2011 #9
    I think it would be incorrect to think of force as a substance or an object, per se. Rather, think of force as being more or less synonymous with, ie., a function of, interaction. Interaction of what, one might ask (eg., in the case of gravitational behavior). Well, that's where a bit of scientifically based metaphysical speculation comes in.
  11. Jul 30, 2011 #10
    No background, I know almost nothing about it except for what I have picked up from daily conversation with people who know something about physics. I will be taking my first physics course this year... sorry if I am not explaining my thoughts in a more practical way haha! Still learning O:)
  12. Jul 30, 2011 #11
    All forces only 'exist' when they have something to act on. They have no separate existance of their own.

    Some forces are local that is they only act at a single point.
    An example would be the contact force between two perfect spheres, which touch at a single point.

    Other forces, such as electrostatic attraction are available in an entire region of space to any and all charges within their region of influence.

    go well
  13. Jul 30, 2011 #12
    I think I am using the wrong words... Force may not be right.. For example, a photon... Is that 2D traveling through our 3D world.. or is it 3D traveling through our 3D world?
  14. Jul 30, 2011 #13
    As far as we can tell we inhabit a universe of 3 spatial dimensions.

    Further, as far as we can tell each of these three dimensions are equivalent - there is nothing to tell them apart.

    If you wish to limit an entity to fewer dimensions why only remove one?

    In other words why 2D, not 1D or even 0D?
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