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Thread: faster than light speed

  1. #1 faster than light speed 
    Forum Radioactive Isotope sculptor's Avatar
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    Let us assume for the moment that we actually could travel faster than light speed.
    Speeding through the universe, would we be able to see objects in our path?

    (justapassing thought)


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  3. #2  
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    No. They would hit us before the light from them became visible.


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  4. #3  
    Genius Duck Moderator Dywyddyr's Avatar
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    Quote Originally Posted by mathman View Post
    No. They would hit us before the light from them became visible.
    So you're of the opinion that light isn't constantly "streaming" from such objects?
    That this light isn't already in transit and that we'd not encounter it as we approach?
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  5. #4  
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    Quote Originally Posted by sculptor View Post
    Let us assume for the moment that we actually could travel faster than light speed.
    Speeding through the universe, would we be able to see objects in our path?
    If you were actually traveling faster than the speed of light you'd be operating outside most of the laws we have concerning interaction between EM fields and matter. For example at the speed of light all photons from in front of you would be infinitely blue shifted.
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  6. #5  
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    Quote Originally Posted by Dywyddyr View Post
    Quote Originally Posted by mathman View Post
    No. They would hit us before the light from them became visible.
    So you're of the opinion that light isn't constantly "streaming" from such objects?
    That this light isn't already in transit and that we'd not encounter it as we approach?
    Herein is one of the problems with imagining an object traveling at greater than c speeds.

    According to every measurement we have made, the speed of light, relative to ourselves is always c. Thus in my FTL ship, my light travels ahead of me and hits the object before I meet up with the object.
    However, according to the object, that same light travels at c relative to him. Thus the light I emit in his direction would arrive after I did. You end up with a contradiction. But this contradiction arises from assuming conditions that the initial postulates forbid.

    Thus, to arrive at a non-contradictory result, you have to throw out Relativity. However, if you do that, you must invoke new rules to take its place. But without knowing exactly what rules you are going to replace Relativity with, you can't work out what the final answer would be.
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  7. #6  
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    well like math been improve from many century to right now the physic to slowly would improve, until now we know there dark matter (still could no be explained clearly what this dark matter contain).


    I think limiting our self to Relativity it is not good, maybe in the future there other would Replace Relativity.
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  8. #7  
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    The trouble is, the question is one of those, "if I set up this impossible scenario, what will happen?" Who knows. Make up any answer you want.

    However, tachyons can almost exist within the framework of relativity, but they do break causality and various other fairly fundamental aspects of physics. So there is no reason to think they do exist. A charged tachyon would emit Cherenkov radiation. Attempts have been made to detect this but, not surprisingly, no evidence of tachyons has been found.
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  9. #8  
    Forum Ph.D. merumario's Avatar
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    If you are traveling at speed c time would stop eventually. When you are traveling at speed faster than c,your lorentz factor would be negative an imaginary number(if my math be right)...

    A proper time that records 10s for an event would be seen as 5.7^-4s which is about 0.57milliseconds(if observer is traveling at 2c)this contradicts special relativity of proper time. Since by SR proper time is the smallest recorded time for an event to occur.

    I.E the observer will see the event before they happen.

    Unless my math with the negative root is wrong!
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  10. #9  
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    You're basically asking, What do the laws of physics say would happen if the laws of physics didn't apply. It's not really a sensible query.
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    Its the way nature is!
    If you dont like it, go somewhere else....
    To another universe, where the rules are simpler
    Philosophically more pleasing, more psychologically easy
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    Das ist nicht nur nicht richtig, es ist nicht einmal falsch!"
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  11. #10  
    Forum Radioactive Isotope sculptor's Avatar
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    Quote Originally Posted by AlexG View Post
    You're basically asking, What do the laws of physics say would happen if the laws of physics didn't apply. It's not really a sensible query.
    Yeh, fersure
    which is why i used "assume"
    .........
    You ever lace your fingers behind your head, lean back in the chair, close your eyes, and ponder the imponderable?
    current physics doesn't seem to work on the micro level(quantum mechanics) nor on the macro level (as/re relative speed of stars orbiting the galactic center), so there is plenty of room for pondering the imponderable------------where are the edges where current physics cease to work?
    ............
    my first thought was the blue shift----------
    and then.........................................????

    (just a passing thought)
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  12. #11  
    Genius Duck Moderator Dywyddyr's Avatar
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    Quote Originally Posted by sculptor View Post
    current physics doesn't seem to work on the micro level(quantum mechanics)
    And THAT is the reason we can't get, for example, lasers to work.
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  13. #12  
    Malignant Pimple shlunka's Avatar
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    Er, my apologies for being uneducated in this area and making a "theory". But, what if I high-speed camera were to be taken on board, running at say, 10x the frames per second of the human eye, would it be able to replay and watch the movement of the bodies passing by?
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  14. #13  
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    Quote Originally Posted by shlunka View Post
    Er, my apologies for being uneducated in this area and making a "theory". But, what if I high-speed camera were to be taken on board, running at say, 10x the frames per second of the human eye, would it be able to replay and watch the movement of the bodies passing by?
    I hate your avatar. Everytime I see it at a glance, it looks like that ugly mug kitten just pooped.
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  15. #14  
    Anti-Crank AlexG's Avatar
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    You ever lace your fingers behind your head, lean back in the chair, close your eyes, and ponder the imponderable?
    I suppose it's easier to do when you don't have to let knowledge get in the way.
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    Its the way nature is!
    If you dont like it, go somewhere else....
    To another universe, where the rules are simpler
    Philosophically more pleasing, more psychologically easy
    Prof Richard Feynman (1979) .....

    Das ist nicht nur nicht richtig, es ist nicht einmal falsch!"
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  16. #15  
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    I'm going to go out on a limb and be supportive of Sculptor on this one.

    I think interlacing ones fingers, leaning back and speculating in a goofy but interesting manner is something all scientists do when they are not doing science.
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  17. #16  
    Forum Radioactive Isotope sculptor's Avatar
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    c'mon Alex

    stop standing in the middle of the field claiming it can't be done.
    just pick up the goddamned ball and run with it.
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  18. #17  
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    Quote Originally Posted by sculptor View Post
    c'mon Alex

    stop standing in the middle of the field claiming it can't be done.
    just pick up the goddamned ball and run with it.
    What for? A pointless excercise in mental masterbation?
    sculptor likes this.
    Its the way nature is!
    If you dont like it, go somewhere else....
    To another universe, where the rules are simpler
    Philosophically more pleasing, more psychologically easy
    Prof Richard Feynman (1979) .....

    Das ist nicht nur nicht richtig, es ist nicht einmal falsch!"
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  19. #18  
    Forum Professor Zwirko's Avatar
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    Quote Originally Posted by sculptor View Post
    ...

    just pick up the goddamned ball and run with it.
    Some people have done that. Here's one suggestion:




    No idea how it was done or if it even makes sense.
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  20. #19  
    Malignant Pimple shlunka's Avatar
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    Quote Originally Posted by Zwirko View Post
    Quote Originally Posted by sculptor View Post
    ...

    just pick up the goddamned ball and run with it.
    Some people have done that. Here's one suggestion:




    No idea how it was done or if it even makes sense.
    You forgot to take the lens off.
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  21. #20  
    Forum Radioactive Isotope sculptor's Avatar
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    Quote Originally Posted by AlexG View Post
    Quote Originally Posted by sculptor View Post
    c'mon Alex

    stop standing in the middle of the field claiming it can't be done.
    just pick up the goddamned ball and run with it.
    What for? A pointless excercise in mental masterbation?
    sure, why not?
    What little of your mental ejaculate comes through on this computer's screen might just be informative and/or entertaining.
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  22. #21  
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    Quote Originally Posted by sculptor View Post
    Quote Originally Posted by AlexG View Post
    You're basically asking, What do the laws of physics say would happen if the laws of physics didn't apply. It's not really a sensible query.
    Yeh, fersure
    which is why i used "assume"
    .........
    You ever lace your fingers behind your head, lean back in the chair, close your eyes, and ponder the imponderable?
    I think you're missing the point. What is the basis by which we can answer the question of what happens if the impossible happens. How can we apply the laws of physics to a situation that violates the laws of physics?
    There are no paradoxes in relativity, just people's misunderstandings of it.
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  23. #22  
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    Quote Originally Posted by sculptor View Post
    Quote Originally Posted by AlexG View Post
    Quote Originally Posted by sculptor View Post
    c'mon Alex

    stop standing in the middle of the field claiming it can't be done.
    just pick up the goddamned ball and run with it.
    What for? A pointless excercise in mental masterbation?
    sure, why not?
    What little of your mental ejaculate comes through on this computer's screen might just be informative and/or entertaining.
    Let's put it this way: It's like asking, "Assuming that 2+2 doesn't equal 4, what does 3+5 equal?"

    Now, it is not beyond imagination to come up with a "math" in which 2 + 2 does not result in 4 (for example, in base 3, 2+2=11), However, nothing in the question hints as to what new math you are using to get this result, And without knowing why 2+2 does not equal 4, we have nothing to base an answer for 3+5 on. It could be any one of countless different "maths", all of which would give a different answer to 3+5(or no answer at all, like in the base 3 example I gave, since the digits 3 and 5 don't even exist in that system).
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  24. #23  
    Forum Radioactive Isotope sculptor's Avatar
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    thanx guys

    It seemed to me that no matter how fast one was going, including faster than c, the light being reflected or emitted by an object in one's path would still be visible. Or blue shifted beyond the visible spectrum?
    If the light is moving toward you at c and you are traveling toward the source of the light at c,
    the photons would still be visible?

    Judging distance, though tricky, should still be possible?

    Even when looking back at where you had been, things would still be visible, just seem to be moving backward through time?

    ...........................
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  25. #24  
    Anti-Crank AlexG's Avatar
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    It seemed to me that no matter how fast one was going, including faster than c, the light being reflected or emitted by an object in one's path would still be visible
    Well that certainly settles that impossibility. Well done making crap up.
    Its the way nature is!
    If you dont like it, go somewhere else....
    To another universe, where the rules are simpler
    Philosophically more pleasing, more psychologically easy
    Prof Richard Feynman (1979) .....

    Das ist nicht nur nicht richtig, es ist nicht einmal falsch!"
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  26. #25  
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    you're welcome

    I do it for the entertainment value.
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