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I have a crazy stupid relativity question May be extremely ridiculous

  1. May 30, 2012 #1
    This question may seem a little ridiculous... I have not taken a course on relativity (I did get a bit of an intro in modern physics class) so maybe that's why I thought of such a crazy thing.

    Anyways, here it is - What if objects that move fast in our eyes aren't necessarily moving faster, but are just experiencing slower time? Even if the time difference is over a billion trillionths of a second, what if we perceive that difference as much more of a speed?

    When I say "moving faster" I mean traveling at a faster rate through the three dimensions of space. What if everything actually moves at the same rate through space but at different rates through the fourth dimension, time?

    I know this is a ridiculous thought and I hope I don't get flamed for it, but it's just something that's been nagging at my mind. I know this is crazy but I think it's kind of fun to think about.
  2. jcsd
  3. May 30, 2012 #2
    First, absolute velocities don't exist. Saying something's moving at 3 m/s means nothing. We need to say that in this reference frame, it appears to be moving at 3 m/s. In that reference frame, the object moving at 3 m/s experiences negligible time dilation. In the reference frame of the object moving at 3 m/s, the first reference frame appears time dilated by the same amount. There's no absolute "this guy's clock is moving slower."

    With that out of the way, yes, at least an interpretation of SR is that time's another dimension, with exchange rate 1 s = 299,720,000 m (or whatever c's value in m/s without the units is), and everything's moving through spacetime at c. In a certain frame of reference, therefore, if another object appears to be moving through space at a certain velocity, its component velocity in the time direction must be reduced (Pythagorean Theorem), and so we see time dilation.
  4. May 30, 2012 #3


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    Actually, this idea is not crazy or ridiculous at all. Recently I have exploited this idea (in a scientific paper published in a peer reviewed journal) to construct a nonlocal hidden variable theory for quantum mechanics compatible with the theory of relativity:
    http://xxx.lanl.gov/abs/1102.1539 [Found. Phys. 42, 632-646 (2012)]
    Expert relativists on this forum may find it interesting.
  5. May 31, 2012 #4
    It so happens that that a vaguely similar nutty idea nags at me too. It seems to me that there should be something better than "space" and "time." The problem is that when I try to apply this idea I get a useless mathematical mess. I decided to leave this up to the geniuses. Let them earn their pay.

    The closest thing to what you are looking for is General Relativity, but it is hard to find a good popular exposition. I'm working on one myself, maybe someday...
  6. Jun 1, 2012 #5
    That can't be: when for example particles are emitted at one point in a particle experiment, the speed of the particles can be directly measured as the length of the apparatus according to us/ the time of flight from one part to the other according to us. One famous experiment in which such things were well examined was the Bertozzi experiment. Such a measurement has nothing to do with the time count as experienced by those particles.
  7. Jun 1, 2012 #6


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    All you have done is redefining "speed". Usually it is defined via coordinate time, for all objects. You instead define "speed" via an individual time for each object such that all objects have the same "speed". I don't know if your idea is useful, but here are some related concepts:

    Proper velocity is defined via each object's proper time instead of coordinate time. Unlike your speed it is not the same for all objects, but goes to infinity when objects approach coordinate velocity of c.

    In Epstein-Diagrams all objects are advancing through space-propertime at the same "speed". Their speed through space and aging rate are just projections onto the space & time dimensions.
    Last edited: Jun 1, 2012
  8. Jun 1, 2012 #7
    Forgive me for a not very detailed comment, because I haven't had any formal education of The Theory of Relativity, and I am relatively new to this forum.

    I would think that everything is moving at different velocities, and that affects the time. Why would we just have slower rates of time? That would be saying everyone is moving at the same velocity, when we know that when you get on a plane and then go to sleep after getting off of the plane, you have 2 different velocities. This idea about time changing and not velocity is strange because we know that when we sleep at home, our own rate of personal time is has an almost negligible difference than someone flying in a plane. If everyone moved at a constant speed, such as 10 m/s, then our time would slow down so much for us when not moving while sleeping from flying on the plane that it would seem like the Universe would be noticeable chaos, the ratio's don't seem to fit.

    And think of this, why would time with reference to this idea slow down at exactly the rate we want it to? It seems as if whenever we want to be travelling fast or slow compared to another persons view, we do it ourselves, we don't let time change randomly and make us happen to seem faster, we would obviously be travelling at different velocities than we would like to probably at some point.
    In order for this problem not to happen, we would have to be able to control time ourselves by somehow our wanting to travel at a different velocity, which would be strange, controlling time instead of velocity.

    Again, forgive me for not being exactly clear with my opinion, I may not have the most mature comment here as I am currently in Freshman year of high school Physics.
  9. Jun 1, 2012 #8
    The reason relativistic effects occur in the first place is because of the observed invariant speed of light. That is, no matter what velocity you travel at, you will always get the same result for the speed of a ray of light. So, time and space adjust by amounts that maintain the speed of light in every frame of reference. A particular observer always feels like his time is ticking at a normal rate, and it is everything else that has adjusted.
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