ELIF: how is time relative?
In: Physics
To properly explain it like you’re 5 is tricky. Best way perhaps is to look at how speed is relative. Imagine you and a friend are on a fast train. You stand in the gangway between the seats. He throws you a ball. How fast was the ball? To you it felt like a normal ball throwing speed. To an observer looking through the window standing in a field, the ball went 300 mph. That’s what makes things ‘relative’. How fast something goes is relative to where the observer is.
Time is the same. Time is just a way of measuring two events. In the same way that a moving train affects how fast a ball looks depending on whether you are inside or outside the train, it also affects how much time has passed depending on whether you are inside or outside the train.
As a real life example, GPS uses satellites to precisely locate where you are. Because the satellite is moving so fast, they actually go out of sync and so need to be adjusted as the satellite is experiencing time ever so slightly more slowly (but enough to move your GPS co-ordinate very slightly).
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