1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Why don't we run out of gravitational force?

  1. Dec 24, 2015 #1
    We know gravitational force is created from the curvature in space time by the mass of the planet, but why doesn't it run out?
     
  2. jcsd
  3. Dec 24, 2015 #2
    Why would it run out? Can you think of any reason a curvature would "run out"? If you have so please share, however if you do not then I can only advise you to revise some GR.
     
  4. Dec 24, 2015 #3

    Drakkith

    User Avatar

    Staff: Mentor

    To bounce of off what Nosebgr said, gravity is the result of the curvature of spacetime, not some finite quantity that is used up over time. Since mass and energy curve spacetime, and both mass and energy are conserved, then it follows that gravity cannot be 'used up'.
     
  5. Dec 24, 2015 #4

    A.T.

    User Avatar
    Science Advisor
    Gold Member

    Because we aren't consuming the mass of the planet.
     
  6. Dec 24, 2015 #5

    Drakkith

    User Avatar

    Staff: Mentor

    I don't know about you, but I'm about to consume the mass of about a thousand christmas cookies...
     
  7. Dec 25, 2015 #6

    mfb

    User Avatar
    2016 Award

    Staff: Mentor

    As long as you don't leave the planet, it is fine.
    If you go to Mars, we'll have to charge mass export fees.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Why don't we run out of gravitational force?
Loading...