Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Is Gravity a force or the absence of a force

  1. Oct 11, 2012 #1
    One thing that puzzles me is that, we are looking for the elusive graviton as a medium for transferring gravity. But if gravity is possibly the absence of force (just a thought ) what would we be looking for. Mass manipulates the fabric of space causing gravity wells or sumps as such. but does gravity have any electro-magnetic potential that can be measured.

    can someone please point me in the right direction?
     
  2. jcsd
  3. Oct 11, 2012 #2

    Drakkith

    User Avatar

    Staff: Mentor

    Gravity cannot be the absence of a force. It is, by definition, one of the 4 fundamental forces of nature. Don't be confused by the "force" term. It is more accurate to describe the fundamental forces as "interactions" instead. Basically it just means that objects affect other objects using one of these 4 ways, which we label as interactions or forces.

    Gravitation is described extremely well by General Relativity, and any attempt to describe it as an "absence of force" would probably be horribly complex and make practically zero sense.

    http://en.wikipedia.org/wiki/Fundamental_interaction

    Is also does have a potential.
    http://en.wikipedia.org/wiki/Gravitational_potential
     
  4. Oct 11, 2012 #3

    PeterDonis

    User Avatar
    2016 Award

    Staff: Mentor

    It depends on how you define "force". If you define it the way Drakkith did, as an "interaction"--basically "a way that things can affect each other"--then gravity is a "force". But in General Relativity, the strict definition of "force" is "something that causes proper acceleration". Gravity does *not* do that--objects whose motion is affected only by gravity are in free fall and feel zero acceleration; their proper acceleration is zero. So in this sense, gravity is *not* a "force".
     
  5. Oct 11, 2012 #4

    Drakkith

    User Avatar

    Staff: Mentor

    Yes, I took "absence of force" to mean the absence of something that causes an interaction, not the absence of something that causes proper acceleration.
     
  6. Oct 11, 2012 #5

    Dale

    Staff: Mentor

  7. Oct 11, 2012 #6
    is not acceleration a constant factor in our experience of the universe. if we are orbiting the sun, and our galaxy spinning is not gravity a byproduct of momentum. Are we not falling around the curvature of the space-time fabric. And because mass bends space we experience gravity at different intensity depending on the mass in our proximity.So by that definition earth creates a more intense curvature of space than the moon so walking on earth is feels like you are being pulled down more because the incline is steeper. that again is just an assumption on my part.
     
  8. Oct 11, 2012 #7

    Drakkith

    User Avatar

    Staff: Mentor

    That is essentially correct, yes.
     
  9. Oct 11, 2012 #8
    thanks for enlightenment
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Is Gravity a force or the absence of a force
  1. Is Gravity a force? (Replies: 5)

  2. The absence of a force (Replies: 32)

  3. Gravity's Force (Replies: 1)

  4. Is gravity a force (Replies: 9)

Loading...