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Another time speed question

  1. Feb 13, 2004 #1
    ok, thought of something here, tell me what you think..........

    if time were to slow down or speed up or stop all together, then start up again, it would be impossible for anyone to realize.
    this is because all action is governed by time, including thought. thought would be non-existant if there were no time to regulate it. also, if it slowed or sped up, so would your thought rate.

    what do you think?
    I am uneducated on this stuff so cut me some slack
  2. jcsd
  3. Feb 13, 2004 #2
    That's not a very meaning full question until you first clearly define time in an operational sense. E.g. define time according to a periodic natural phenmomena and then compare all other periodic phenomena with that one phenomena. As such it makes no sense to refer to all processes slowing down since you've not given a benchmark to explain what it is slowing down with respect to.
  4. Feb 13, 2004 #3
    ok, your sort of confusing me, but i'll try to be more specific.............

    if im traveling at 9/10c parrallel to a beam of light, then would I see the light that im following change color? probably not because the light traveling between me and the beam im parrallel to would still be a constant, am I right? Would I only see a color change in all the other light that would be traveling to and from the direction I was going? and would I not notice that my own personal time was slowing down? If I could travel at the speed of light for a moment(a moment relative to a still observer), would my existance simply freeze for that moment? would I not remember anything about that simple moment?
  5. Feb 13, 2004 #4


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    An excellent deduction! You are not the first to get there, but you are in great company, Eintein's line of reasoning that lead to SR started at much the same point. The idea that movement through time is just as relative as any other form of movement has profound ramifications.

    For instance, if you are in a spacesip and enter an area of space in which time is slowed, your watch would slow down, but so would the clock on the wall, your heartbeat, and your brain's ability to process information and thought (probably the most fundamental way in which we "experience" time). To you, inside the ship, nothing has happened. To an outside observer, your movement through time has slowwed down and, if you could see the outside observer, you would say that his passage through time has sped up. This is the phenominon of "time dilation".

    However, if both of you were to enter the same area of space at the same moment, or simultaneously enter two different areas with the same properties, niether one of you would notice any change in yourself or each other. If the entire universe were to slow uniformly throughout its entire volume, nobody in the universe would be able to observe the change.
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