Why isn't there a metric measurement of time?
480279
because it relies to the events which can't be measured metrically anyway. Weeks follow the approximate lunar circle, there's 365 days in a year etc.\n\nalso, imagine we would divide a day into 100 hours. 1 hour would last only 14 minutes, which would be way too few and confusing. \nIf we divided a day into 10 hours, an hour would last 2 hours and 64 minutes. this would probably be too long, and we wouldn't have enough hours to properly determine a time of day...\n\nAn hour was determined as 1/4 of the time when the shadow of a pole travels a 60 degree angle or something... i THINK. I might be wrong on this, high school phisics is a LONG time ago. \nAnyway, it was old Sumerians or Babilonians who determined it like that and ever since it wasn't changed. We're too used to these units now, we can't just change them without causing a massive MESS :D
125374
this is a sincere question   that  sure opens  more questions.....including  memory functions....there is much  misuse today  and  much misleading  ...how can i  call it  even  information....but  try  any  mathamatical  formula  with  time  in  it  sit  back  and  ponder  the  various  integrations  that  time  takes part  in.......try  many  formulas......time  may not  be  only a clock....check  into  what  physics  calls  a  half life...but  also  wonder  what  produced that  to  get  it  there.....interesting   spell  time  backwards...you get?.....as far  as  travel....or  what  is  backwards  or  forewards......remember  the  guy  who  jumped  out  of  his  bath  and  ran down  the street   yelling    i have  found  it......thats  what  happens to  most  of  us  ...when  we  reach  a degree  of  exploratory  freedom....good  luck...hope  this  helps
10953
well yeah... \nwell we dont have any definitive start or end point, so it's only relative to itself meaning that you can only measure a change in time, not how much of it you actually have. \nyour actual question is a little ambiguous, if this isnt what you meant, you can add some to the question,  are you looking for an explanation of how high velocities distort time or something, because I can explain that if you would like, just add it onto the question or make a new one or something.
200117
distance= rate*time\ntime= distance/rate
459592
Let's suppose you had a theory which explained that something would take t seconds.  Another theory says that it would take t + x seconds.  You want both theories to be true.  What do you do?  Well, if you are a genius like Einstein you say that time stretched from t to t + x seconds when you went from one theory to the other.\n\nTake another example.  Suppose you are running a race with a stop watch.  At the end of the race your stop watch says you took 60 seconds.  My stop watch says you took 90 seconds.  The logical explanation is that one or both of our clocks are wrong.  But, if you are an Einstein, you say that time was stretched, and your clock moved slow relative to my clock, but is still accurate.
549573
Time is a measurement. Before Creation, God existed in Eternity. Since eternity is measureless, no, time wasn't...or in other words.. there was no time before time started, at the beginning of CREATION.
1151942
Metric system?????\n\nWe BARELY know the system we're using now!!! Anyone who knows their Multiplication Table is considered a Mathematical GENIUS!!!
1033398
1. Time is a variable and not a constant. It ran backward only in Harry Potter's Vol 3 using Time Machine\n2.The perpendicular distance is the shortest distance\n3.Why not\n4.The variable nature of time can be felf only with objects moving with a velocity that approaches that of light. The theory of Relativity cannot be proved wrong because no one has understood it completely
965397
Travelling back in time is not allowed by einstein's theory of relativity...however if you can instantly teleport youself to some faraway star,say a 101 light years away, you might be able to catch einstein receiving his nobel prize!! as stated earlier, there is no master grandfather clock that is regularly ticking away the seconds..rather that rate is adjustable...but one may zip into the future..consider an example where you are on a space-ship at a speed of 0.99990 c that is going away from the earth and coming back..in your time frame say,it takes about twenty years..using lorentz transformations, the time for your to and fro motion is close to 450 years!!
667978
Time is an arbitrary concept. Different cultures have counted the years from a different starting point. Clock time is just an arbitrary convention that made it easier to schedule work, travel etc. In math or science problems, we may have an equation talking about how something happens in relationship to time, but the time that equals zero is still an arbitrary concept, based on when something started or when we began counting or whatever. \n\nIn temperature, we have a concept of absolute zero, which is defined to be the fundamental lowest bound of temperature. Scientists have actually calculated what that absolute zero temperature must be and have even developed a scale, the Kelvin Scale, that starts from absolute zero. (There's still an arbitrariness to that scale because the "size" of one degree Kelvin was based on the size of degrees in the Centigrade scale, which was based on dividing by 100 the differential between the freezing and boiling points of water at sea level.)\n\nIf there is an absolute zero to time, we don't yet have any way of calculating what it is. If it turns out that the Big Bang theory is true, there would be some time when the universe began that could be considered the absolute zero of time for the universe. Would that be when time began? Maybe...
405952
Ask around if any of your friends have a GPS system.  There is your example of a daily-life example of the theory of relativity.  The Global Positioning System would not be able to give you very accurate locations if it did not take the corrections to time and distance from both special, and general reletivity into account.  I am pretty sure that it is the first piece of public consumer-grade equiptment that relies on our understanding of General Relativity.
1045387
GOOD QUESTION: well done! There is not really any such thing as time, it is merely our way of describing a particular abstract concept. If it was a solid physical reality it surely couldn't be relative. Lets all go and read Einstein and try to figure it out!
89468
Ya Time is just a measure of change... If there is change then you can say that there is time... No-time isn't a "theory" it's an idea, a thought game.
12025
no, because time is only a mesurement that we humans have come up with.  if anything, you can't travel through time because there are an infinite number of universes constantly being created.
365798
http://physics.nist.gov/GenInt/Time/time.html
1183829
It isn't measured, it is calculated. The speed of light in miles per second is multiplied by the number of seconds in a year to get the length of a light year in miles. \n\nMeasuring the speed of light can be done in many ways, and is not as hard to do as it was before electronics were invented. Early methods relied on flashes of light from rotating mirrors miles apart. Today laser pulses are timed very accurately with electronics over short distances. Also, amazingly, Maxwell's equations calculate the speed of light theoretically from a number of other unrelated electric and magnetic measurements.\n\nMeasuring the distance to remote stars is another topic, but the results are usually expressed in light years because the numbers are just inconveniently large when expressed in miles.
728817
Time is relative.  It doesn't really exist.  Time is effected by the speed of motion, and is not an object.