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Calculate how fast a person is moving when the world is moving slower from their view

  1. Sep 12, 2012 #1
    Not sure where to post this or if this can be solved, but I couldn't figure it out because math and physics are clearly not my strength :)

    I am writing a book where one of the characters has the ability to speed her travel through time. Basically, she is in a type of warp bubble, for lack of a better word. From her perspective, everyone is moving slower, but she is still able to interact with the world around her. On the flip side, she moves very fast according to everyone else.

    From her point of view, an object that is moving at 58m/s looks like it is moving at 1m/s. What I am wondering is how fast she would move if she were to walk (average walking speed 1.389m/s) or run (average running speed 4.47m/s)? Is it a 1 to 1 ratio, as in, would she walk 58m/s + (her speed)? This doesn't seem correct to me, but I'm not sure how I would calculate her speed.

    I realize this is fictional, but I am a stickler about being historically and mathematically accurate in all of my writing and any help or just a calculation would help me immensely. Thank you in advance for your help.
  2. jcsd
  3. Sep 12, 2012 #2
    Re: Calculate how fast a person is moving when the world is moving slower from their

    I think this is what you're asking:

    58 m/s is to 1 m/s as x(her walk speed) is to 1.389 m/s. so her walking speed is just 1.389*58 m/s.
  4. Sep 12, 2012 #3
    Re: Calculate how fast a person is moving when the world is moving slower from their

    That's simple enough. I think I was making it more complicated than it had to be. Thank you for your assistance.
  5. Sep 13, 2012 #4
    Re: Calculate how fast a person is moving when the world is moving slower from their

    Why do you think that from her perspective everyone else would appear to be moving slower?

    If she is moving forward through time 58 times faster than others, what she sees in about one second of her time is what the others do over about a minute of their time... the others will appear to her to be moving 58 times faster than normal.
    Think of it like this; you are watching a video at normal speed and you decide you want to "move forward in time faster", so you press the fast forward button. Now you are moving through video time faster than the normal rate of the video... what does the video look like to you? It looks sped up and everything to you appears super fast. The video is the normal people and you are the one moving forward faster.

    As I think about it, this probably means that the normal others can't see her because she only exists for them for an instant as she passes through their present moment. This is a potential problem for any interactions she wants to make with the normal others.

    Now, if she is doing all this with a warp bubble thing, I'm thinking you may have some wiggle room for interactions, but there will be a few things to work out for any interactions between her and others outside...

    If the boundary of this bubble is a discrete surface, then all the above problems seem to apply, but if the bubble boundary is a diffuse continuous gradient over which the difference in her time and others is gradually shifted from inside to outside the bubble, then you might be in a better position to have interactions between her and the others outside.

    To do that you may have to decide if Relativity is going to prevail concerning the speed of light. If the speed of light stays constant for all observers both inside and outside the bubble, then you have some interesting things that can happen. If you decide that the speed of light inside the bubble is going 58 times faster than outside the bubble, you have a different set of interesting things to work with.

    If you can get a few pieces of this to stick together, then the rest should all follow consistently enough to support the story without being too far of a stretch for scifi.

    You might spend a few days reviewing threads in the Relativity forum, not so much to grasp it, but to get a sense of some of the basic ideas from the questions and discussions.
    Good luck.
  6. Sep 13, 2012 #5


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    Re: Calculate how fast a person is moving when the world is moving slower from their

    She is moving slower through time. She has one minute, where others just have one second.
    It is not possible with relativity, but I think that is the purely fictional part here.

    There are other issues, too - what happens to air molecules she breathes? If they move with their regular speed, it would be extremely cold to her. If not, they would be extremely hot for the environment. A similar problem exists with pressure. In general, the boundary between the "time speeds" will lead to many problems, if you take it serious.
  7. Sep 13, 2012 #6
    Re: Calculate how fast a person is moving when the world is moving slower from their

    "...one of the characters has the ability to speed her travel through time."

    I take this to mean that she travels forward in time faster than the others, in this case 58 times faster...

    So this would mean that one minute of her time would cover the same span as 58 minutes of time for the others. Travel through time (normal or sped up) has to be viewed as analogous to a distance dimension (a displacement through time).

    There are two parts; the time displacement, and the local perceived duration of making that displacement.

    Normals perceive one minute of duration across a one minute time displacement.
    The faster woman perceives about one second across this same displacement.

    This does look like she is moving slower in some ways; but what she is doing slower is perceiving the events within the displacement. She is moving through time faster, but she is perceiving at her local rate, so almost a minute of outside activity happens within one second of her local time - her perception will be that the outside is flashing past 58 times faster for her... this may lead her to think she is going more slowly.

    If you define the speed of travel through time to be:


    the normals go at 1 and she goes at 58/1=58; so she goes faster.

    If you define it as perception/displacement

    the normals go 1 and she goes 1/58=.017; so she perceives slower.

    When she goes faster, she perceives slower compared to normal, and the world around her appears to change 58 times faster. That is consistent with the idea that she is moving through time 58 times faster - and consistent with the idea that her perception is 58 times slower when doing this.

    I suppose what this means is that any interactions she intends with others is going to need to be carefully planned and set up in advance because she will appear to the normals as almost frozen still, unable to speak, write, gesture, or otherwise communicate except by having arranged pee-staged props and circumstances...

    I'm starting to think that the effects the op is looking for is actually a woman that travels more slowly through time so that for her she perceives herself to be going perceptually faster. This is what would allow for her to appear to herself that she can walk faster, move faster, and otherwise do everything faster than the other people around her. If she was moving through time 58 times slower than the others, she would experience almost a whole minute of time to do what she wanted during what for the others would be just one second. This would actually make communication and interaction easy for her by manipulating things around her, writing notes, making recordings, and would give her the advantage to have 58 time more time to think about her questions, answers and other actions, which to the others would appear to be almost instantaneous in response... If she was clever and well equipped, she could research heavily any situation on the spot and proceed with confidence... would always win every game show in which she participated, for example.
    Last edited: Sep 13, 2012
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