This text was originally submitted to the 2013 Flame challenge question of the Alan Ada center for communicating Science. The question was: What is time? Due to the regulations it had to be short and hat to be readable for high school students. The students themselves had to choose the winners. So here you go:
Once there was a little girl who was very interested in music and dancing. Her name was Emmy. Later, after going to school and college, she helped explain many things in science. One of the things she was thinking of is very much related to our this year’s topic of flame challenge: What is time?
Imagine a ball on a flat table in a room where absolutely nothing moves. There is nothing about the ball that can be related to time: no past, no present, no future, it all looks the same no matter how long you wait.
Once you push the ball to roll it, things are different. If the ball could talk, it could tell you about the time before it was pushed, the time it was being pushed and a time after that. By pushing the ball we have “interacted” with it by pushing it with our fingers, thereby exchanging energy with it. Same is with heating up a soup, turning on a lamp or doing whatever else.
So Emmy found out that there is a connection between exchanging energy and the concept of time. If these energy exchange events happen regularly, they can actually be used as a means to keep the time. That’s why something always moves or blinks in clocks!
The more often these events are, the more suitable they are for time keeping. If you choose the olympic games as a reference, all you can tell about a sports event in your local school is that it took place before or after the last Olympic games. It can be anytime within 4 years. For more accuracy, people use smaller time intervals such as days, minutes or seconds as unit of time.
By the way, can you find out more about Emmy?