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What's the time?

  1. Mar 1, 2010 #1
    Hi everyone. This probably isn't the right place for people like me to ask stuff like this but I've searched the internet and am finding it hard to get any answers so I thought I'd post here. If the measurement of time is something we do by counting predictable repetitions, and these can vary dependant on relative speed to other objects etc. etc., how can people make statements like, 'we know what happened 1 second after the Big Bang? Surely our measurements of one second has absolutely nothing to do with our universe at that point in 'time'. Thank you and I hope someone can explain this to me!
  2. jcsd
  3. Mar 1, 2010 #2
    "Surely our measurements of one second has absolutely nothing to do with our universe at that point in 'time'."

    Why not? Assuming I was there at the big bang and was sitting in some (very) shielded ship and watched my clock, whats wrong?

    EDIT: Seconds in the modern world are defined as so many 'shakes' of a certain frequency of light.
  4. Mar 1, 2010 #3
    Ok, if seconds is measured in 'shakes of light' then I guess that makes sense as light is always constant. Thanks for your help!
  5. Mar 16, 2010 #4
    Time is a spatial dimension, just like space. The concept of "progression through time" really is a meaningless statement. Time is a coordinate system. You specify two positions in time. Each time position represents a defined set of coordinates for the space dimensions it represents. Draw a line between the two time positions and you have just drawn a timeline that defines how the defined spatial coordinates in space change from one time position to another time position. That's all time is. There's no direction. There's no "progress". Just an infinite series of change in spatial coordinates defined at infinite time points.

    As an observer (that's us), our brains have to somehow interpret the series of change. Hard to do when when all time exists simultaneously just as all space exists simultaneously. Your birth, childhood, adulthood and death.....exist at once. Our brains cope by assigning order to these individual time positions of our lives. And hence, this results in our interpretation of time as "progression" in a single direction in a timeline.

    Of course, all this comes with significant philosophical ramifications of life, religion, consciousness and existence itself....which I won't get into at the moment.

  6. Mar 16, 2010 #5
    Our time is based how long it takes our planet go around the sun
    Months, days, hours, and seconds. We compare this time to other things we see.
    It is all a comparison.
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