TIME NOTION DEFINITION HOW TO

All moving clocks run slow-not just light clocks.īut the effect is insignificant except at speeds approaching that of light. A thought experiment using a light clock reveals why this is so. When the airborne clock returned to Earth, it was a tiny fraction of a second behind the one that remained on the ground. Scientists synchronized two highly accurate atomic clocks and then flew one around the Earth aboard an airplane. Researchers have actually observed this effect, which is only detectable at high speeds. The idea that a second is not always a second is one of the most surprising findings of Einstein's Special Theory of Relativity. When the clock moves, the time between ticks is longer. The pulse bounces back and forth between the mirrors at a constant rate.

The clock 'ticks' when the pulse reaches the mirror at the top of the clock and 'tocks' at the bottom. Imagine a clock that consists of a pulse of light and two mirrors, one at the top of the clock and one at the bottom. The effect of time slowing down is negligible at speeds of everyday life, but it becomes very pronounced at speeds approaching that of light. Time is relative even for the human body, which is in essence a biological clock. Although this 'light clock' experiment is a hypothetical one, the same effects are true for any timepiece, from old-fashioned grandfather clocks to atomic clocks, the most accurate time-keeping devices available. To explain this bewildering result, physicists point to a thought experiment involving a clock that uses light to mark time. The faster a clock moves, the slower time passes according to someone in a different frame of reference. A second in one reference frame may be longer compared to a second in another reference frame.

TIME NOTION DEFINITION HOW TO

Just as observers in two different frames of reference don't always agree on how to describe the motion of a bouncing ball, they also don't always agree on when an event happened or how long it took. In the Special Theory of Relativity, Einstein determined that time is relative-in other words, the rate at which time passes depends on your frame of reference. Time seems to follow a universal, ticktock rhythm.

Time notion definition