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

If SR were wrong

  1. Mar 4, 2006 #1
    If SR were wrong, in what kind of difficulties and paradoxes would we run? What would an universe with instantaneous signals look like? Is such universe even possible?

  2. jcsd
  3. Mar 4, 2006 #2


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    It might look how pre-relativistic mechanics says it would look.
  4. Mar 4, 2006 #3
    You would have a continous patchwork of kludges added in order to make things fit. The first kludge would be to fix things in such a way so that Maxwell equations would look invariant when viewed from relatively moving inertial frames. And it gets nastier from there.....
  5. Mar 6, 2006 #4
    Some of the interpretations that depend upon c as the limiting speed limit may not have any effect on the way things work - for example we know that em waves travel at c, we think electostatic and gravitational effects are also similarly limited - but we don't have very good ways to verify the speed at which fields produce forces at a distance. So if by some chance these field effects travel at some other speed than c, then the universe will behave as it does, but not for the reason we think it does
  6. Mar 6, 2006 #5

    Be more specific. Do you mean if the principles SR is based on are wrong, namely the constancy of the speed of light for all inertial observers, and the principle of relativity? Or do you mean the conclusions derived from those?

    It depends on what part is wrong. If you mean the second and not the first, well then our entire system of mathematics doesn't apply to the universe as a descriptive tool. And if you mean that light is not the same to all observers, but the principle of relativity still holds, then we get pre-relativistic mechanics. If you say light is constant, but the laws of physics are not the same in all inertial frames, or both are wrong, then really weird things happen.
  7. Mar 6, 2006 #6
    If realtivity were wrong, the universe would be the same as it is now. Except it would have more red faces.
  8. Mar 6, 2006 #7
    I mean pre-relavistic mechanics (and pre-Maxwell). No constancy of light, Galilean relativity apply in this universe, you can travel as fast as you like.

    Is causality violated in a Galilean universe?
  9. Mar 6, 2006 #8
    We would have serious trouble making our synchrotrons work.
  10. Mar 6, 2006 #9


    User Avatar
    Staff Emeritus
    Science Advisor
    Education Advisor

    Not really. Most of us would have been DEAD, including you, because the stuff we depend our lives on would have caused major crashes or wrong medical diagnosis.

  11. Mar 6, 2006 #10

    George Jones

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    No, because there is absolute time and absolute similtaneity.

  12. Mar 6, 2006 #11
    Is there still time to retreat my question? It looks fairly dumb now to me:grumpy: .
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook