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Why move faster?

  1. Mar 24, 2004 #1
    From what I understand Time Travel depends on us moving faster than the speed of light. But why do we have to move faster? Couldn't we slow light down? If we were to slow light down, we could walk faster than light. Is this possible?
  2. jcsd
  3. Mar 24, 2004 #2
    If the bullet is laying on the table, then I am faster then a speeding bullet?....so perhaps you can see why....?

    time travel requires time, so please, first, find the "Universal metric of Time" in the Physical universe....Ps there isn't one...
  4. Mar 25, 2004 #3
    If someone can think of an idea, then someday it can be accomplished. How do you plan to slow light down? Plus, if you slowed light down, would it still be light? Or might it become something different? (sorry if these are stupid questions, but my name is ignorant1 for a reason:frown: )
  5. Mar 25, 2004 #4
    Light already slows down when it passes through a medium other than void. Apparently, and I would take this information with a big spoon of salt, scientists were able to slow it down to 1mph:
    But again, this doesn't mean time has slowed down in itself. Maybe for someone inside the medium in which light slows down, time changes... but for the rest of universe, where light still travels at a constant speed of c, nothing has changed.
  6. Mar 26, 2004 #5
    Actually, I believe he is correct, to a point. However, there is a fatal flaw in his assumptions. Time would speed up for the light, rather than slowing down for everyone around it. This goes to what Mr. Parsons indicated. Time does not slow down universally as a result of light slowing down locally.
  7. Apr 7, 2004 #6
    Ya tryn to slow down light is kinda like Q's solution in one of the star trek episodes of trying to change the cosmological constant to move a moon i think it was.

    You could slow down 1 beam of light possibly, but for any of this to really matter you would be talking about trying to slow down light all over the universe.. somehow changing the actual physics of the universe instead of working within it.
  8. Apr 7, 2004 #7
    Joao Magueijo and VSL?


    Our goal was to drastically slow down light, which travels through empty space at the universe's ultimate speed limit of nearly 300,000 kilometers a second. We saw the first sign of light pulses slowing down in March 1998. As happens so often in experimental physics--because it can take so many hours to get all the components working together for the first time--this occurred in the wee hours of the morning, at 4 A.M. By July we were down to airplane speed. At that time I had to go to the Niels Bohr Institute in Copenhagen to teach a class. I remember sitting in the plane marveling that I was traveling "faster than light";--that I could beat one of our slow pulses to Denmark by a full hour.

    Last edited by a moderator: Apr 20, 2017
  9. Apr 8, 2004 #8
    Err..I guess slowing down the light speed will not shorten the distance between Earth and other planets, let me know if i am wrong. I think we want to travel faster than light is not for just faster than light is to travel to a through a distance with shorter time.
  10. Apr 8, 2004 #9
    Why would you try to travel a physical distance in order to travel in time?
    Time is not a physical dimension.
    The reason it is suggested to travel at the speed of light is because time becomes unstable at the that instant allowing an entry point to the time dimension. a tear in the thread. So theoretically if one could find a place in the universe where time is naturally unstable then one maybe able to find the entry point. Perhaps its best we don't find any tears because we could pull the whole sweater apart
  11. Apr 8, 2004 #10
    Wouldn't hurt to get a new sweater anyway, this one is all dirty and faded.
  12. May 11, 2004 #11
    "there is more than one way to skin a cat"

    so what you were originally saying (i think....) is that you want to slow light down to travel trough time? how would this work? would it, in sense, slow time down, would it create a rift in the ever-faithfull time-space thing, or would it do something else?

    (by the way, i'm actually interested in this, so please just put an answer, instead of arguring over who is right?)
  13. May 30, 2004 #12
    Since Sol2 brought up the discussion of Dr. Maguiejo, has anyone been able to test his theories yet?
    I was able to get a copy of his first article, and presented it to my lower division physics prof. He poo pooed it as soon as I mentioned it.
    Obviously, guys like Dr. M. didn't get to where he is by making up phony ideas for the sake of being published.
  14. May 30, 2004 #13
    I dont understand why traveling faster the light will take you back in time, Other then a weird analogy that (i think) Einstien Said.

    If your looking at a clock and traveling away from it at the speed of light, the clock will have appeared to stop!, if you were traveling faster then the speed of light wouldn't it be logical to see the clock going back in time?. But you wouldn't really be going back in time. Just seeing things go back in time.
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