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Taking Away, the Moments That Make Up a Dull Day

 You have probably heard the expression "time is relative", 
 but you probably haven't spent a lot of time worrying about time.
 The thing is, no one really understands what time is.
 In early times, people used time to measure the seasons. 
 When the weather cycled back to the same conditions, 
 people said that a "year" of time had passed.
 We now know that what they were actually measuring 
 was how long it took the earth to complete an orbit around the sun. 
 The measure of time began as the measure of movement.
 The other early basic measure of time was the day. 
 It was found to be the time it took for the earth to revolve on it's axis.
 The later invention of hours, minutes, seconds and various partial seconds 
 were just divisions of a day (like slicing pizza).
 The movement of the earth was thought to be as regular as clockwork.
 That is, until our measuring abilities got very good.
 The point is, that all units of time are just measures 
 of how long it takes something or other to move a certain distance, 
 or rotate through a certain angle.
 Time can not be measured in the absolute. 
 It can only be measured in terms of some standard rate of motion. 
 There can be no absolute measure of time.
 We can do thought experiments with this idea:
 If absolutely everything instantaneously doubled it's velocity, 

 how could you tell?

 If absolutely nothing moved for a "while" 
 could you ever tell how much time had passed while everything was stopped? 

   copyright 2005 Bruce Kirkpatrick

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