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

Move one, How long does it take for another one to move?

  1. Mar 2, 2010 #1
    Hi,all, problem:

    2 stars, distance is 1 lightyear.

    If I move one star, will the other star move 1 year later?

    Basically, I want expose the problem that, how fast does a field travel.

    Thanks In advance!
  2. jcsd
  3. Mar 2, 2010 #2


    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    Are you inquiring about the speed of the propagation of gravity? As far as I know, this is still undertermined. You might find all sorts of answers, from infinite, to 10 times the speed of light, etc.; but I believe the most widely accepted theory at this point in time says that it travels at the speed of light. I will ask the moderators to move this post to the special/general relativity section, if it belongs there.
  4. Mar 3, 2010 #3
    Thanks for replay. I am wondering, is the speed of information(field) travel at the speed of light, then about wavefunction sperad all over the space? refer to my another question, see:


    Thanks a lot!
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook