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The speed of time

  1. May 1, 2003 #1
    Read the other one this is messed up
    Last edited: May 1, 2003
  2. jcsd
  3. May 1, 2003 #2
    Time is an invention of man simply to calculate night day and when earth makes it around the sun, right?

    Not according to Einstein.
    Einstein proposed that time was relative. He said that the speed of light was the only constant in the universe and that time depended on the position and velocity of an object. His idea was that the speed of light was the only universal absolute, and nothing could exceed that speed; that to go the speed of light time would have to slow down.
    The conflict of this, however, is that Einstein said that for an object to travel the speed of light time must slow down (Because, of course, velocity is distance divided by time). This would mean that time need not slow down for any mass in motion until it comes upon the speed of light; this would contradict the idea of a man walking would age less than a man sitting. Since the latter was proven we must assume that this theory is true, not to disprove the light theory, but my idea is that Einstein didn't quite take that idea to the full extreme.
    The fourth dimension is time. Imagine time as a platform that is pushing you forward at the speed of light. You and your friends each have their own "platform". You would arrive about 670,000,000 miles away in exactly 1 hour. But say you walk at a speed of 10 miles per hour on your platform. You would exceed the speed of light by 10 mph, but if einstein was correct in saying that the speed of light cannot be exceeded, then time would be forced to slow down. You would arrive at the same place at the same time as your friends on their platforms, but time would have slowed for you.
    Still again, as the pattern goes on, what if you started running at the speed of light on your platform. To keep you from exceeding the speed of light, wouldn't time be forced to "stop"?

    While this theory is of course yet to be proven, it does propose that time, although relative to the observer, is constant to the universe.
  4. May 1, 2003 #3

    Ivan Seeking

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    Well, you're getting the idea. He said that C is a constant but not the only constant. He says nothing about what happens if one could get to C, only what happens as we approach this apparent speed limit. You need to do some more reading but you're starting to get it. :wink:
  5. May 1, 2003 #4


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    If you take a look at the Topic, "Time Dilation" in the Physics Forum, you'll find a paraphrase of Brian Greene's description of this phenomenon. Basically, it says that the total volocity of any thing is c, and that under normal circumstances, most of this volocity is dedicated to progress through time. However, as you have stated, any movement through one of the other dimensions is subtracted from forward progress through time.
  6. May 2, 2003 #5
    speed of time

    i have a few idea on this....first i think speed of time is a new idea that is worth to be consider.

    why our time slow down when we are moving( no matter what speed)? IMO, because time need to chase us. the rate of time that flow from 0 to 1 second is the same for stars far away if they speed is the same to earth speed. when you approaching the speed of light, time need to chase you, that's why you know that your time become slower compare to an observer in earth.
    when you enter a room, you see everythings didn't move(man standing still,water stop in the air, etc) then you said that the time in the room has stop. but does it really? just because things didn't move in space doesn't mean the time have stop. from here we can know the relationship of spacetime.IMO time is more than its definition, time is a space(still thinking,sorry).
  7. May 2, 2003 #6
    You know, although I have read that the speed of time may be an illusion, I still get the notion that it may have a speed. Can't the rate of entropy increasing be measured? Or does it not make sense to say that time has speed? Because time allows for speed, both speed and time would be intertwined(sp?)...
  8. May 2, 2003 #7
    One shall be careful trying to associate time with dimension. Dimension is freedom to move, but there is not much freedom to move in time (say, nothing can go back and forth in time). So time is a coordinate, not a dimension.

    (That is why tiny "i" in front of it in all SR, GR and QM equations when you try to mix it with space - to distinguish it from spatial coordinates which ARE the dimensions (degrees of freedom) we know.)
  9. May 2, 2003 #8
    Totoro, thank you for your efforts, but i didnt understand a damn thing you said.

    So alexander, you don't believe that Einstein was correct in saying time is relative? It's just a coordinate, never changing? What if, like i said, you were going the speed of light, and you accelerated to C + 10 mph. Time would be forced to slow down 10mph/C of a second in order for you not to exceed the speed of light. In your vision, you would be going C + 10, but when you looked at your watch, it would be going (at such minute speeds over C it wouldnt be noticed to the "naked" eye) slightly slower. This is to mathmatically compensate for your excess speeds.

    Y = 1 year

    1 light year = C + 10 mph
    (10mph/C * Y) + Y

    *Because Distance/Time = Velocity

    Therefore time would have slowed 10/C for as long as you were traveling at that velocity.

    PS try to keep the physics terms simple LOL havent had physics, 10th grade.
  10. May 3, 2003 #9
    So....are you taking time as a spatial dimension....
  11. May 3, 2003 #10


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    No... dimension is the number of linearly independant directions.

    What i? The only way time is distinguished in SR and GR is from the signature of the metric, which is chosen to agree with reality, not because time really isn't a dimension and we're fudging the mathematics to make it look like a dimension.
  12. May 3, 2003 #11
    Hmm....dont know what i was thinking there...i dont think it is a spatial dimension...I did not mean for time to be thought of as the "platform". The "platform" i was talking about would be massive.

    But i do believe that time is more of a "free" dimension than the coordinate idea we associate it with. I believe there is[I/] freedom to move in time, we have just not reached (and may never reach) the point at which it varies. Which does contradict a "proven" theory in a way, by saying it doesnt vary until it reaches the speed of light.

    I think that time is relative to speed(and of course to the observer). I think time varies inversley with Speed
  13. May 3, 2003 #12


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    Greetings !

    Since Newton at least (I think) time was
    considered to be a parameter that discribes
    the rate of occurance of physical processes.
    SR was formed by combining the constancy of
    the speed of light (c) with the above assumption -
    simply applying it. That is also the way time
    is percieved today.

    Live long and prosper.
  14. May 3, 2003 #13
    So my whole theory is nothing new?
  15. May 3, 2003 #14


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    Greetings The_oMeGa !
    I appologize, but after reading your messages
    I still do not understand what that theory is.

    Just think of time as a clock. Everything and
    everyone has it and the clock makes certain
    all the laws of physics stay the same for
    that thing/person. Why would someone
    consider it to be a dimension ? Because
    a dimension is some continuum - like the
    real line R in math. Now we have spacial
    dimensions that discribe the relative
    position of an object to us and we have
    the time dimension to discribe the relative
    point in time of an object.

    Now, before relativity we thought everything
    is simultaneous and the time was the same
    for every object. But, this is wrong and
    in fact unintuative when you consider it
    a bit more and when you know light has
    a limmited velocity. For example, if I send
    a spaceship to a certain galaxy and the
    cute alien in that galaxy knows emmidiately
    it's coming because he can see it - there's
    no need for some different time for him relative
    to me. But, if light and every other interaction
    is limmited to c and less he will only see
    the spaceship departing millions of years later -
    thus he has a different time value for this event
    relative to me.

    A usefull term to discribe this is a "light cone".
    Basicly, I consider an event to be a definite
    point in space-time (definite space and time values)
    relative to me, then time is the line passing
    through that point and the center of a 2D (for
    a simple example) cone and the growing weidth
    of the cone are the spacial dimensions - volume value,
    with the relation between these two parameters
    defined by c - the speed of light (the limmit
    for the speed of any interaction spreading in
    space). Thus I get a light cone for my event.

    For my space-time coordinates I get a certain
    sequence of light cones - events. But, for
    a different observer the sequence may be different
    depending on his relative (to me) motion through

    Live long and prosper.
  16. May 3, 2003 #15
    C=T=G all the same.
  17. May 3, 2003 #16
    Basically, this is my theory:

    Time is relative to the observer, and varies inversley with the speed of the observer but only when the observer has reached the speed of light.

    Say you are going at the speed of C and you increase your speed by 10Mph. If Einstein was correct in saying that C is the universal speed "limit", then time will be forced to slow down 10/C of a second to mathmatically (Distance/time = Velocity) compensate for this.

    This is fairly simple, which is why I asked if it had been stated before.
  18. May 4, 2003 #17
    This is my personal thoughts on the subject, The speed of light is the time barrier. The reason light seems to be constant at that speed is because the photons that do manage to increase to C+10 break the time barrier. I think this barrier is the same for Gravity, light, and Time. What I do not understand is why. Why is 186000 mps a constant for these things? What happens after that velocity? time travel, dementional travel, disintigration, etc. I imagine if you were in a ship and you broke the speed of light you would see flashes of light, similar to a sonic boom from a jet. They use to believe that the sound barrier could not be broken and that something wierd would happen. Consider this if you are in a ship and traveling at the speed of light and you decide to go 10 mph faster a flash of light happens and the ship you see has already past you a year ago but your just now seeing it or something along thoughs lines. You are traveling at c+10mph and just get there or wherever just a little faster than c. No hocus pocus about it.
  19. May 4, 2003 #18
    Can you expand on how 'inversely' time varies?
  20. May 4, 2003 #19
    A line, drag? A line describes a 2D surface...but then you said you used 2D for simplicity. But, you also included a 3 demensional figure, a cone into the example, so now I'm a little bewildered.
  21. May 5, 2003 #20
    Is time a direction?

    If you think so, then how about energy, or mass, or temperature?

    That is exactly what we do (fudging the mathematics for our convinience). Because math is strictly logic, it shows us that time and space don't mix, forcing us to separate them by i=(-1)0.5
    Last edited by a moderator: May 5, 2003
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