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Could time as a dimension have property that would behave like energy ?

  1. Nov 8, 2011 #1
    Hi, this is my first post, and I'm not an expert of any kind or do not believe I am.
    I have always been fascinated by science, but I some time ask myself some questions,
    here's one I don't seam to find much info. I found a lot of treads that mentioned the
    subject but nothing that actually discussed the topic.

    I was wondering if time slows down for an object that approach the speed of light,
    in comparison with it's environment, and that the energy required grows exponential,
    could it be that space time is applying a negative equivalent force on the object.
    Could it be that the frame in which the object occupy has less (time energy), but
    more of other energy, I know it's not anywhere this simple, there would be a change
    in the gravitational field, and much more implication.

    My main point is, Could time as a dimension have property that would behave like energy ?
    What would be the implication ? How could we calculate it or could we even calculated it ?

    I apologize in advance if the subject has already been talked about (aldo I couldn't find
    anything with the search option), either way I would very much like to hear peoples though
    on the this.

  2. jcsd
  3. Nov 8, 2011 #2


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    Think about driving a car (with the pedal glued down) where you must drive at 60mph all the time.

    You can drive 60mph due north, but if you turn slightly East, some of your 60mph motion is diverted from North to East. If you turn all the way East, all your 60mph is diverted to Eastward motion.

    All massive objects must move through 4-dimensional space time (xyzt) at the speed of light.

    An object that is unmoving in spatial dimensions (x y and z) must be moving at c in the time dimension t. The faster an object moves through x,y,z or t the less it has to move through t. If you are travelling near c through the spatial dimensions, your velocity through t is reduced to near zero.

    It's overly simplistic but it might make some sense.
  4. Nov 9, 2011 #3
    Thanks for the quick reply, your answer is quite similar to most answer I have seen.

    My problem is when it comes time to try to calculate a way to find potential differential
    between the 2 identical objects (the one at rest and the one close to the speed of light).

    Let see is you can see why I'm having a problem.

    We calculate the speed of light by m/s, but the meter is measured by the speed of light.
    Hence if time is a constant the speed of light could slow down or accelerate and still
    essentially have the same speed. And when the time slows down for an object going
    close to the speed of light I imagine the meter change to compensate.

    Now this means that the mass goes up with speed, from an observer point of view of
    course. Any one know the rate at which the mass would increase ?

    See I'm not looking to know were mass would tend to go, that was easily explained.
    It's easy to say something will tend to infinite mass, but how much did the mass
    increase by the time it got to .6c, how much energy does it have, and than compare
    it to how much energy was use to get it there. That's what I'd like to do.

  5. Nov 9, 2011 #4
    That's true, but I think this is just an accident of how meter and second is defined. If the speed of light actually changed then a lot of physics experiments would come out wrong, and the definitions would be revised to correct this.

    You might think that if the meter and second somehow were getting smaller or larger together then it wouldn't be noticed. But the physics of atoms would have to change, because in some of the fundamental constants the meter and second don't cancel. This idea has been looked into by examining light from the beginning of the Universe, and the physics seem to be the same there. So the best bet is that nothing fundamental has changed.
  6. Nov 9, 2011 #5


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    The length and time contraction happens as a result of the discrepancy in velocities as measured between observer and observed.

    In its own frame the observed does not experience any length or time contraction.
  7. Nov 9, 2011 #6
    Sorry, I might have over simplified 3 am and was getting sleepy.

    What I was getting at is, if the speed of light look like a constant from all time frame,
    could it be because the same problem I pointed in calculating the speed of light can
    be applied to how we calculate acceleration. Which seam to make me believe that
    if we could approach the speed of light, not just time would seam to slow down from
    the point of view of a stationary object, but because of the augmentation in mass,
    I could imagine the space occupied by that fast object be contracted, by it own
    gravitational pull, creating a distortion of what a observer on the object going close
    to the speed of light would perceive has distance.

    If it where the case that approaching the speed of light does compress space, then
    is it not a valid argument to say that an object slowing down from close to the speed
    of light would expand space ?

    But I still come to this problem distance is measured by light, and light is measured
    on distance that is calculated by light. This mean all calculation is only valid in

    What do you guys think.... is my reasoning acceptable.

    Deleted part,don't know what I was thinking when I wrote the following, sorry please discard....
    (and we can't really know if the universe is expanding or not. We
    can only assume, that the universe has a positive expansion if time is constant,
    time has a negative expansion if space is constant or a combination of both could
    see any one variable be positive or negative if the variation if the other variable
    can account for the difference. )
    Last edited: Nov 9, 2011
  8. Nov 9, 2011 #7
    Well, I guess I wasn't searching for the right thing before, because a quick search today
    introduced me to EST theory. I'm sure it's going to be nice read.

    I'd still be interested in hearing your though on the subject.
  9. Nov 9, 2011 #8


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    While the author of EST does have a few published papers, it doesn't strike me as being particularly mainstream. In particular, if you adopt the EST papers viewpoint and try to talk to people here about relativity, I predict some communications problems.

    I'd like to say that I've read your thoughts in detail, but I really haven't had time. But I think I"ve noticed a more-or-less usual omission in your thoughts, and that's any discussion of the relativity of simultaneity.

    I think you're going to have a really hard time getting correct answers out of relativity without this key concept, which doesn't seem to fit naturally to me into any "expanding spacetime theory". Perhaps you've found a way to fit it in and I've missed it.

    I'll recap the issue, under the assumption you aren't famiiliar with it.

    The usual example of this, due to Einstein, involves a moving train, and a pair of events, say lightening strokes, that just happen to occur at the same time in the frame of the train station, one at each end of the train.

    See for example Einstein's original description at http://www.bartleby.com/173/9.html

    You can add for ease of understanding the argument (though it's not necessary for the argument) some specific mechanism that makes the events occur simultaneously, though getting them to be simultaneous and also coincident with the train is going to take a bit of work.

    Now, if two signals are emitted at the same time, they must meet in the midpoint between the signals. THis happens in the station, for instance - the two signals, simultaneously emitted in the station, meet together at the midpoint of the station.

    But the train has moved since then, and the two signals cannot meet in the middle of the train, because the train is moving.

    The only way to avoid a logical paradox is to realize that the events that were simultaneous in the station frame are not simultaneous in the train frame. And this realization doesn't have anything to do with expanding space, that I can see. But it's unavoidable, and rather important.
  10. Nov 9, 2011 #9
    Thanks for the heads up, still have to read it before I decide what I think about it.

    I guess this post can be closed, the post name is kind of misleading, and I figured out
    what I was doing wrong. Unfortunately it just made things a lot more complex than I
    had anticipated

  11. Nov 10, 2011 #10


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    Noeether's theorem certainly suggest an interrelationship between time and energy. But it doesn't have anything to do with "time slowing down", and everything to do with the class of theories that have a Lagrangian.

    See for instance http://math.ucr.edu/home/baez/noether.html for a somewhat redable summary (which may still be challenging), the Wiki article on the topic quickly dives into a mathematical morass without saying much to guide the non-specialist reader.
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