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Seeing into the past through a mirror going fater than the speed of light.

  1. Jun 26, 2012 #1
    I'm not sure if this is the correct area to post this question, but I don't know where else it could go. If it is incorrect, can someone please move it to the correct area if that is possible.

    This is a purely hypothetical question, and I am by no means good at physics (just starting out).

    If it were possible to get something to go faster than the speed of light, then is it possible to view our planet's history in reverse?
    My idea of achieving this is to attach a giant mirror to the back of a spacecraft capable of faster-than-light travel. At a certain point, put the mirror in place and stop. Depending on how far you travelled and at what speed faster than light, you would see a certain amount of time in the past, by getting in front of the light.
    I have proposed getting in front of the light and stopping, because I am unsure of a way to reflect light backwards that is infront of you. If that was possible, then you could view our history in reverse.

    I would not be surprised if many things that I have said either don't make any sense to others or are completerly incorrect or impossible, but it has been an idea that I have wanted to ask others about what they think.
  2. jcsd
  3. Jun 26, 2012 #2
    This is an ill-formulated question, you cannot have objects traveling at the speed of ligh, let alone traveling faster than light. So, your question is akin to: "if 2+2=5, is it true that 3+3=7 or 8?"
  4. Jun 27, 2012 #3


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    Unfortunately, even if you could instantly place mirrors out in space to reflect back to us what happened many years ago, it would take just as many years for the light to travel back to us so that we could see what was going on, wouldn't it? So what I think you really want is mirrors that have already been in place for the past many years so that the light would already be on its way back to us, don't you agree? So if you wanted to see what was going on 10 thousand years ago, you would look at a mirror that was 5000 light years away, does that make sense to you?

    So I guess it's already too late, don't you think?
  5. Jun 27, 2012 #4
    Fair enough, I did not think of the fact that it would take so long to get back. Even if you could get the light from in front of the spacecraft, you would see it in reverse, still at a normal rate. So if you wanted to see far in the past, you would have to wait far in the future...

    And I do see that the answers would probably be a wild guess anyway, due to the nature of the question.
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