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

Seeing the PAST not FUTURE

  1. Jan 30, 2013 #1
    Let's say theoretically we can setup a perfect environment with two mirrors at a great distance apart. The distance is great enough to allow light to reflect off one mirror and not reach the other mirror until a full minute has elapsed. Could this in "theory" create a window to see one minute into the past?
     
  2. jcsd
  3. Jan 30, 2013 #2
    Sure, but using this definition it's much easier to see into the past. Just look up at the stars and you're seeing them as they were thousands upon thousands of years ago.
     
  4. Jan 30, 2013 #3

    ghwellsjr

    User Avatar
    Science Advisor
    Gold Member

    Why do you need two mirrors? You could put just one mirror at a distance of 30 light-seconds away and then watch yourself as you were one minute earlier. You'd need one powerful telescope to resolve anything though. But you could easily prove that it worked by comparing the image of your clock in the mirror to what it says when you look at it directly.
     
  5. Jan 30, 2013 #4

    ghwellsjr

    User Avatar
    Science Advisor
    Gold Member

    Yes, using the definition of simultaneity that the stars we see in the sky are as they were thousands of years ago, we can look up in the sky and see them as they were thousands of years ago. There is no independent proof like there is in my previous post.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Seeing the PAST not FUTURE
  1. Future and past (Replies: 21)

Loading...