1. Not finding help here? Sign up for a free 30min 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!

Particle in free fall problem

  1. Apr 9, 2007 #1
    "Under what conditions does a geodesic represent a possible wordline for a particle in free fall, parametrized by proper time."

    I can only think of one conditions - the fact that the metric ds squared is positive. Is this enough?
     
  2. jcsd
  3. Apr 9, 2007 #2

    Dick

    User Avatar
    Science Advisor
    Homework Helper

    Possibly something like, "if acted on by no nongravitational forces". GR only absorbs gravitational forces into the metric. Though possibly that violates the condition of 'free fall'.
     
    Last edited: Apr 9, 2007
  4. Apr 9, 2007 #3

    Dick

    User Avatar
    Science Advisor
    Homework Helper

    Nope. I think you are basically right to begin with. 'Free fall' should exclude nongravitational forces. But I think the condition that they might be looking for is that the particle is massive. Otherwise proper time=0 is quite acceptable.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Particle in free fall problem
  1. Free-falling problem. (Replies: 1)

  2. The free particle (Replies: 1)

  3. A free particle (Replies: 5)

Loading...