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Time Definition-Forth Dimention

  1. Apr 25, 2003 #1
    http://www.aphysics.netfirms.com [Broken]
    Time Definition
    If we go to search everything about definition of time finally will be a disillusion because of confusing definitions.
    My theory will brink you clear vision about fog and confusion.

    Here the definition of time: Time is 4th dimension and is equal to radius of sphere where the space is defined. Compression or expansion of space will generate compression or expansion of time. All four dimensions are correlated and cannot be separated. More concise: space is surrounded by time or defined by time and part of time. This is way so far time cannot be seen because is hard to be seen from inside.
    Simple Math of Time Definition

    At any moment a partition of time d(t) is a partition of radius d(r) d(t)=d(r) and include space d(s)
    The vector r(t) is: x = x (t)
    y = y (t)
    z = z (t)
    Any movement in space (x, y, z) will be: r = (x, y, z,)= xi + yj + zk
    If r(t) derive twice R
    First derivate r’(t) = v (speed).
    Second derivate r”(t) = a ( acceleration)
    Speed vector v(t) = r’(t)=( x’(t), y’(t), z’(t) ) = x’(t)I + y’(t)j + z’(t)k)
    Acceleration vector:
    a(t) = v’(t) = r”(t) = ( x”(t), y”(t), z”(t)) = x”(t)I + y”(t)j + z”(t)k
    Here how space is surrounded by time.
    Last edited by a moderator: May 1, 2017
  2. jcsd
  3. Apr 25, 2003 #2
    I have a problem with this. I have always felt that spatial dimensions are dependent on time. For example, suppose I were to document my whereabouts using coordinates such as (t,x,y,z), where t is time and x,y,z are space. Right now, I could be (April 25 5pm, 40*N, 80*W, 20ft above sea level). These are crude examples, but bear with me.

    If only the time coordinate existed, I could know the other three because at that time I can only be in one place. For the time coordinate of April 25 5pm, I can only be in that aforementioned spot. However, given the three spatial dimensions (40*N, 80*W, 20ft above sea level), this is not enough information to derive the time coordinate, because I could be at this exact spot tomorrow (disregarding earth's rotation, etc)!

    Thus, I feel it is only proper to say that "The compression or expanion of time will generate compression or expansion of space." Overall, a small point, but I feel it is a valid one.
  4. Apr 25, 2003 #3
    Quite simply, time is the increase in entropy, and can be used as a coordinate.
  5. Apr 29, 2003 #4
    Time is not the increase in entropy. It is the direction in which entropy increases, yes, but the increase of entropy is just an event, not a dimension.
  6. May 5, 2003 #5
    Locutus, if time travel were feasible, then time would no longer be regaurded as a coordinate but as a spatial dimension instead. (Not that time travel will ever be feasible)
    Just a thought.
  7. May 5, 2003 #6
    r=sqrt(x2+y2+z2)? But this is space again (r is length), not time.
  8. May 5, 2003 #7
    Re: Re: Time Definition-Forth Dimention

    What about r = 10 billion light YEAR?
  9. May 6, 2003 #8
    What do you mean?
  10. May 6, 2003 #9
    I mean a distance can be measured directly at unit of time .
    This r is radius of sphere, universe in this case. Though on my glance this is the time only. Time which had passed from a moment when "inverse BB" began.
  11. May 6, 2003 #10
    You can't measure distance in units of time. Distance and time are different quantities - they have different properties.

    To express distance in units of time, you may multiply time by proper dimensional factor (say, speed of sound) and then you may say that the size of universe is about one quadrillion sound-years. So what?
  12. May 6, 2003 #11
    The Light upon its "travel" creates the illusion of space.
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