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Hypothetical scenario spacecracft moving faster than c

  1. Jul 3, 2012 #1
    How will light switched on from a space-craft moving faster than c appear( hypothetical space-craft) to a ground observer??
    I am new to this forum and i am unfamiliar regarding threads, but some guy locked my previous thread, its absolutely unfair,citing the reason space-craft cant travel faster than c!
    If the same logic was used, there would have been no SCHRODINGER's CAT, EPR, etc
  2. jcsd
  3. Jul 3, 2012 #2


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    You need to learn about relativistic velocity addition.


    The reason why your other thread was locked as because you made some assertion of something moving faster than c! If you don't know, ASK, but do not make some wild guess before you learn things. How you ask things is as important as what you are asking.

    Edit: furthermore, please read the Relativity FAQ subforum:

    https://www.physicsforums.com/forumdisplay.php?f=210 [Broken]

    Last edited by a moderator: May 6, 2017
  4. Jul 3, 2012 #3

    D H

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    Biological, read your private messages.
  5. Jul 3, 2012 #4


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    Since no current scientific theory allows for this, it cannot be answered as a scientific question. You first need a theory that allows it to even begin to answer this - and both formulating and discussing such a theory are outside the scope of this forum (until developed enough to be published as a possible generalization of known physics).
  6. Jul 3, 2012 #5
    I agree with you Zapper Z, but the reason i asked this was they had used the scenario i posted to explain the fact that c is ultimate speed in the chapter Special relativity in the book,
    Last edited by a moderator: May 6, 2017
  7. Jul 3, 2012 #6
    You are basically asking what the law of physics would imply if the laws of physics weren't valid. Questions like this make no sense, and physics cannot answer them.
    It's like asking "If a man could be pregnant, how long would pregnancy last?" The situation is impossible, so the question makes no sense.
  8. Jul 3, 2012 #7
    I dont seem to understand why so many members are regarding this as a question which does not make sense!
    If Schrodinger was alive, he would have been probably be saddened by the arguments posted here, Schrodinger's CAT also does not make any sense, so does the famous MAD SCIENTIST paradox or even the EPR paradox, But these are the paradoxes which created intense discussions in Quantum mechanics and modern physics!
    so going by the arguments posted, these would be nothing but statements which make NO SENSE!
  9. Jul 3, 2012 #8
    I don't see why you say Schrodinger's cat does not make sense?? There is a physical theory which describes what happens to Schrodinger's cat. There is no physical theory which deals with spaceships going faster than c. It is an experimental fact that spaceships cannot go faster than c.
  10. Jul 3, 2012 #9


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    And what's is the problem with that?

    You need to understand what a "postulate" means. Einstein first made that postulate that c is the same in all reference frames. THEN he derived all the consequences of that postulate. He arrived at many predictions that have been confirmed, and it also solved for a very important problem in classical E&M, which is the non-covariant of Maxwell equations under Galilean transformation.

    So the postulate that c is the limit in speed "makes sense" in the sense that it agrees with experiments!

    BTW, do not bring up these "Schrodinger Cat" etc. argument just to justify what you are doing. You are doing nowhere near what is associated with these scientific arguments. You are new here. Think of the impression you are giving - a new member suddenly dictating how the forum should be run. It makes you come off to be utterly arrogant. Is this an accurate impression of you that you want us to have?

  11. Jul 3, 2012 #10
    I thought i have mis-read Schrodinger's cat!
    In his opening statement at copenhagen, he began with saying "consider the hypothetical scenario.................................................................."
    Leave alone that, i also believe that the equipments required for conducting this experiment is of un-imaginable precision and advanced technology!
    So educate me regarding the result of this experiment if it has been already conducted!!
    Leave this experiment, what about the other paradoxes???
  12. Jul 3, 2012 #11
    This has nothing to do with the thread at hand. This thread was about moving faster than c, not about Schrodingers cat. I told you that the difference between Schrodingers cat and this thread was that Schrodingers cat has a physical theory which can be used to predict future events. Moving faster than c does not.

    Your thread has been sufficiently answered. Do not start a new thread on this.
    Last edited by a moderator: Jul 3, 2012
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