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

Why is all motion relative?

  1. Nov 4, 2014 #1
    Why can't motion be relative to space?
     
  2. jcsd
  3. Nov 4, 2014 #2

    Dale

    Staff: Mentor

    How fast is space moving? I.e. a spaceship is sitting in space, how would it measure its speed relative to space?
     
  4. Nov 4, 2014 #3
    I don't know how fast space is moving. I didn't even know that space could move.
    You wouldn't be able to measure speed relative to space.
     
  5. Nov 4, 2014 #4

    Dale

    Staff: Mentor

    Exactly. That's why motion can't be relative to space. At least not in any scientifically useful sense.
     
  6. Nov 4, 2014 #5
    So does space move? What is space?

    If space is a thing which moves, surely there must be some way of detecting it.
     
  7. Nov 4, 2014 #6

    Dale

    Staff: Mentor

    So running your logic in reverse, since there is no way to detect its movement then surely it must not be a thing which moves.
     
  8. Nov 4, 2014 #7
    How do you know space moves? What is space?
     
  9. Nov 4, 2014 #8

    Dale

    Staff: Mentor

    I never claimed that I do know this.

    I am not comfortable continuing a conversation when you respond to every comment I make as though I had said the opposite of what I did. Thread closed.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Why is all motion relative?
  1. Why of all things LIGHT? (Replies: 11)

  2. Relative motion (Replies: 6)

  3. Relative motion (Replies: 5)

  4. Relative Motion (Replies: 18)

Loading...