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Two kinds of time

  1. Jan 22, 2004 #1
    Two kinds of "time"

    A gravitational field condenses space while slowing time. If we look at space and time as comprised of finitely-sized "points" (rather than geometric points), we see that the effect is opposite for each one. In space the points are condensed in the direction leading to the gravitational field, getting more condensed the closer you go to the center of gravity of the object exerting the force of gravity. In time the points are expanded in the same direction, getting more expanded the closer you go the center of gravity. What this means is that the closer one is to the center of gravity of an object, the more length contraction (lengths getting smaller relative to areas away from the gravity) and time dilation (time moving slower relative to areas away from gravity). Gravity's curvature of space is often represented as an indention in a plane.

    I propose that "flowing" time is different from dilatable time. Gravity's effects on time seem to be opposite of its effects on space- if we represent space's curvature it is an indention, time's curvature a bump (the same thing we would expect to find in space as "antigravity"). Here are two diagrams of space and time (1-dimensional representations in a 2-d diagram):

    Figure One
    Figure Two

    Figure One- The blue line is flat spacetime (how it would look if there was somehow no gravity). The black line is actual spacetime (how it looks WITH gravity). Above the black line is space (gravity indents it, condensing it), and below the black line is time (gravity bumps it, expanding it). As is apperent, the black line is spacetime, and when percieved from the top it arises in space, from the bottom it arises in time.

    Figure Two- The blue line, again, is flat spacetime, and the black is actual spacetime. This time, however, there are two additional lines- a purple and a dark blue. The purple line is an imaginary divide between time and space. Below the purple line is time, above is space. Space is experienced from the exterior of the circle, time from the interior of the circe. The dark blue line shows a space point corresponding to a time point. This was the original concept I came up with, but Figure One (probably wrapped into a circle) seems a more likely scenario, lacking a repeat of the same information twice.

    This explains length contraction and time dilation (relativity, essentially), but we lack "flowing" time, time which has a corresponding time point for every instant in time. For this reason I have labelled the time of spacetime "Time A" and the time of flow "Time B". Here is Figure Two with alterations to depict Time B:

    Figure Three

    Time B is NOT relative- it flows at the same rate for all things. This model eliminates the need for an existing past or future. In relativity, if there was no past or future but only a present, moving onwards, a part of the present with time dilated to be slowed down relative to the rest would find itself isolated in its own section of time with nothing else present (since the slow-moving area would be outpaced by the fast-moving area). A concrete past and future must EXIST in order for this not to occur.

    However with Time B this is not required. Time A deals with time dilation, but Time B moves at a fixed rate; meaning that an object with "slowed-down" time is still moving through Time B at a fixed rate, but time points (shabon-damas) in Time A have expanded, slowing the object's experience down. This model also seems to effectively prohibit time travel, seeing as only Time A is relative and the location of the present only concerns Time B.

    As a final note, Time A has the same number of dimensions as Space, whatever that number may be. A three-dimensional model of Space and Time B would be a sphere, and a three-dimensional model of Space, Time B, and Time A is, of course, impossible- we require four dimensions for that.

    Any comments, additions, subtractions, etc?
  2. jcsd
  3. Jan 23, 2004 #2


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    And interesting proposal.

    I do have one problem with it; your initial premise on which the rest of the model is built. I'm not convinced that the conflict you have set out to resolve exists. As I understand it, space and time are different attributes of a single thing. Therefore, contraction of one should result in dilation of the other. Even the basics of special relativity, relativistic velocities result in contraction along the dimension in which the object is traveling (length contraction) and dilation along the time dimension. Am I correct in understanding that you disagree with this assessment?
  4. Jan 23, 2004 #3
    "A gravitational field condenses space while slowing time. If we look at space and time as comprised of finitely-sized "points" (rather than geometric points), we see that the effect is opposite for each one."
    Figure One

    I have not disagreed with that statement at all- what I've disagreed with is the nature of this time dimension. There are two main reasons for this:

    1) If time is another dimension, what gives it preference over length or width or heighth? Why does our velocity in any of these dimensions result in contraction of that space dimension and dilation of the time dimension? I've explained that in my proposal by giving dilatable time (Time A) the same number of dimensions as Space- in fact it IS space from an opposite point of view. Time A is not really another dimension- spacetime is like a flat piece of paper with indentions and bumps on it(to use a two dimensional analogy, true spacetime is 3-d with 4-d indentions/bumps). Space is the top of the paper, Time A is the bottom. They are two parts of the same thing, but "opposite".

    2) Without a non-relative flowing time, the past (relative to the least dilated object in the universe) seemingly has to physically exist (for the reasons stated in the last few paragraphs of my original post). If the future does not exist as well, matter is being created with the passage of time, which seems unacceptable. If the future does exist as well, what gives us the sensation of moving through time? Time dilation undeniably occurs, but if it actually changes the speed with which we move through "flowing time", these problems occur. With my model of spacetime the time portion cannot represent flowing time anyway, because it is the 3d universe (with 4d indentations and bumps) from "below"- each time point (shabon-dama) corresponds to one Space point. In "flowing time" (Time B), each shabon-dama corresponds to a VERY large number of space points, namely every point in the universe at the given instant. For this reason I seperated the notions of spacetime and time dilation from the notion of "flowing time", Time B.

    If we live on a four dimensional brane's surface, the "top" of the brane is space and the "bottom" is Time A (if the brane is a 4-d sphere the "top" is the outside and the "bottom" the inside). Time B is the fifth dimension, a non-relative time dimension through which we travel at a constant rate(like the classical idea of time).
  5. Jan 24, 2004 #4


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    Who says it gets preference? Its just another dimension like the 3 space dimensions. Time dilates and space contracts by the same amount.
  6. Jan 24, 2004 #5
    That's exactly what gives it preference. Why doesn't width or heighth or depth dilate? You've given preference to the time dimension by seperating it from the space dimensions in the way it functions- thus there must be something different about it. In my proposal the difference is that it is actualy 3-dimensional and an exact (but opposite) copy of the topography of the space dimensions- thus width is not equal in status to Time A, and neither is depth or height. Time A contains these three dimensions.
  7. Jan 24, 2004 #6
    For the sake of discussion, let's put aside curvatures in space-time for the moment and focus on flat space-time.

    There really is no intrinsic difference between space and time. It's common to think of space-time as having three dimensions of space and one of time which are absolute in direction. Space-time, however, is composed of four dimensions which are mutually perpendicular with no set temporal or spatial directions. The differences between space and time arise when measurements between different inertial frames are made.

    All massive objects in space-time have a constant speed equivalent to c and this velocity is always in the time direction relative to that body. Another way of saying this is the magnitude of the four-velocity of any massive body is always equal to c and points in the time direction. Essentially, all massive objects move through time at the same rate. The catch is that my time direction may be different from yours depending on how we are moving in relation to each other.

    Example: If I am moving at a very high velocity with respect to you, you will measure me moving through time at a slower rate than you (time dilation). However, I will not measure my time to slow down. I still move through time at the same rate, just in a different direction. Here's an analogy: We can walk in the same direction (forward) at the same speed. If I decide to move in a different direction, say 45 degrees to the right, but maintain my original speed, you will see me moving slower in your forward direction. I am still walking forward but I see you moving slower in my forward direction. We each have the same speed but are moving in different directions that we each call forward and thus have different velocities. Such is motion in space-time.

    You can say that space-time is made up of four equivalent dimensions. Any differences in space and time depend not on intrinsic difference between the two but on our own velocities relative to each other. There is no need to invoke a separate, absolute time direction to account for clock discrepancies and other relativistic effects.
  8. Jan 24, 2004 #7
    I understand relativity perfectly well; but time still seems to make no sense as a single diminsion. I realize that the diminsions are at right angles to each other and do not have an "axis" with location, but are only defined relative to each other. But by singling out time as the diminsion that dilates while the others contract we've contradicted that statement. If I'm moving in a certain direction and am experiencing time dilation along a "time" dimension, and then suddenly turn 90 degrees and move at the same velocity, that same "time" diminsion is dilated the same. If all the dimensions were equivelent, we should see the dimensions which I had previously been travelling along dilate; or perhaps the dimension at right angles to the plane formed by the two upon which I've travelled. The fact that this 90 degree turn causes contraction in first one dimension then another, but both times dilates the same dimension, implies that the dilated dimension is somehow different than the others.

    For every point in space at a given instant there is a number which can describe that point's time dilation relative to a vacuum. A map of the total of all these values is my Time A- just like a map of the total of all the values for each point's space contraction is Space. My Time B is required to make this universe move and pass through time as it does now- since Time A is a collection of values, just as space is (in fact they are the same collection of values, gravity values, interpreted in two opposite ways). Time B, as a necessity, seems to be nonrelative- it is experienced differently depending on an objects Time A location, but there is no reason to think objects actually pass through it at different speeds- if there was, an object's velocity in Time B would be proportional to its location in Time A with no regards to space. Meaning we have one dimension through which things move at a speed dictated by locations of those objects on one side of a plane (a plane in our analogy, space in reality), while their location from the other side of the plane influences the objects size within that plane. Why wouldn't Time B be proportional to length contraction, and "time dilation" be length expansion in Time A and nothing more?

    Since Time A and Space have to be equally important, it seems illogical to think that another dimension would act according to one's laws and not anothers- so if you accept the Space and Time A model of spacetime it seems necessary that Time B is nonrelative.

    If you don't accept the Space and Time A model of spacetime, it seems odd that we have three dimensions in which length contracts and one in which it dilates...
  9. Jan 24, 2004 #8
    Fair enough. I meant no insult to your knowledge and I apologize for posting things of which you are already aware. I just wanted to be be clear plus it was as much for my own benefit as anyone else who may view this thread.

    As far as relativistic effects, I do not view them as actual, physical changes in distance and time. If I decide to move at a high velocity relative to you, I am not causing you to physically shrink or that of the space in which you find yourself. Nor am I causing your time dimension to 'physically' dilate. It's a matter of perspective.

    Analogy: If you hold a ruler in front of you with it's length oriented along the vertical axis and then rotate the ruler around the horizontal, you will see it's length decrease in one direction and increase in another. It did not physically shrink but just changed it's orientation. Likewise, acceleration in space-time can be viewed as simply a rotation. If I move at high speed relative to you, you will see my length decrease as my time increases (slows). From your frame of reference, I have simply rotated my length so that it is oriented in a different direction. I haven't physically altered any dimension.

    I guess I just don't see the need for this other time dimension but do not be dismayed. We just have a difference of opinion. I'm not an expert, far from it. I might be missing something. Completely possible.

    You might consider a mathematical treatment of your idea. To be honest, I'm having difficulty following your theory. I'm not suggesting it's a failure on your part. I may need to 'chew' on it for awhile. :smile:
  10. Jan 24, 2004 #9
    Hello, please forgive my ignorance, as I just wanted to jump into the conversation here in efforts to learn something new and share my thoughts/opinions (please correct them if they are incorrect).

    To my understanding, gravity appears to be directly proportianal to the mass of an object (the more massive the object is for a given area, the greater the gravity field strength of that object).

    Also, to my understanding, we observe time by observing light reflections. We do not actually see an event happen when it actually happens, but rather we observe the action stamped 'sequencial animated frames' of light reflections that are reflected from an object at a clocked frame rate (what ever that clocked frame rate of normal 'time' is).

    Plus, we know that gravity fields do effect light and light reflections, in that it can divert is path of flow (as in event horizons) and even slow its reflection speeds (as in black holes).

    Also, the faster an object travels through space, the more massive that object becomes - the more massive it becomes the greater its gravity field strength becomes - the greater the gravity field strength the more effect it has on light reflections - the more effect it has on light reflections the more our perception of time of that object is influenced.

    I don't think that gravity is effecting time, but rather gravity is effecting our means of observing time (the light reflections from that gravity object).

    Does this sound correct?

    Thank you
    Last edited: Jan 24, 2004
  11. Jan 24, 2004 #10
    Not quite... It's a rather common idea though. Remember that sight (light) is not the only way we percieve the passage of time- we have computers with clocks and memory, we have our own minds, etc.

    If all the gravity did to time was bend light and thus alter our perceptions of time, then standing right next to a black hole and facing towards it would give us one sense of time, while facing away would give us the opposite sense. Gravity bends spacetime- its bending of space is seen through length contraction and gravitational attraction. Length contraction goes like this: You are in deep space viewing the Earth (in real time- we're disregarding the fact that the light takes time to travel to you, because it is irrelevant to our current discussion) and you see a rod standing upright on the ground. Based on your instruments the rod is 10 feet tall. Now you go and get the rod and bring it out to deep space with you and measure it again; this time its length will be slightly GREATER than 10 feet (only slightly because the Earth's gravitational field is relatively weak). Gravitational fields shorten everything in them in the direction of the center of gravity; from within the field you don't notice the change, but from outside of it you do.

    This isn't just compression because of the attraction of gravity; it returns to normal away from the massive object. It isn't compression at all; it's length contraction, an aspect of relativity.

    Also, as you no-doubt know, gravity attracts matter. Space is actually warped so that other matter is attracted to a gravity-inducing object. It's like iron balls on a stretched out sheet. If there is one ball on the sheet and you set down another, the new ball rolls towards the first. This is an analogy for gravity.

    Space and time, however, are the same thing; spacetime. Not only is space warped by gravity, time is as well. An example of this is being near a black hole. If you could lower yourself on a rope to inches above the event horizon of a black hole (and somehow not die, heh) and stayed there for a small amount of time and then returned, centuries (maybe mellinea!) would have passed for the people on Earth.

    Your post was correct up until the part I quoted. Gravity warps spacetime (so does speed, and expiriments have been done to verify this), it doesn't simply attract objects. Sorry for the huge long post, and doubly sorry if it made no sense! I'm tired... :P. I hope I was some help to you in any case.
  12. Jan 24, 2004 #11


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    To put it another way, I think the only real problem with the statement...
    ...is that it implies there is a difference between those two things.

    Since we know that time is relative, our observation of time is the only measure of its progress. If we observe it as being slowed, then to us, it is.
  13. Jan 25, 2004 #12
    Good Morning, thank you for your replies and explanations, they are both helpful and informative. Ok, I believe I understand what you are saying, please let me restate it in another way in order for you to verify that I do actually understand what you are saying:

    Gravity effects the energy correlation of the sub-atomic structures of an object in some manner (as in resistance to its interactions) that causes the sub-atomic structures of those objects contained within the gravity field to interact with one another at an altered rate of speed (which would then alter its decay rate or half life), in relation to objects contained outside of the gravity field.

    The altered rate of speed is then determined by the field strength of the gravity field that the object is in, and effects all objects within the gravity field the same amount for a given field strength. Since time is the relative sequential clocked record of both decay and interaction of sub-atomic structures of an object, gravity is said to effect time for that object, which is then observable by observing the radiated energies from those altered objects and comparing them to previous observations (in efforts to determine the decay rate - or the 'time offset'). Is this correct?

    If photons are simply one form of radiated energy waves from an object (an object that meet specific requirements for radiating or reflecting photons), then (in the case of black holes) if the influence on the sub-atomic structures of those objects are changed drastically enough then those objects that once met the requirements for radiating or reflecting photons could no longer meet them, thus resulting in the photons no longer being present within the black hole, and simply shows or mimics the objects altered energy levels and state of being outside of the black hole. Is this correct?

    Thank you
    Last edited: Feb 6, 2004
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