8 Super Simple Ways To Explain Complicated Science

7. Time Dilation = Driving A Car

The Tricky Bit Time dilation is part of Einstein's theory of relativity. It is the principle that time can pass at different rates for different observers either moving at different speed or at different distances from a gravitating mass. In special relativity, a person's velocity affects the speed at which time passes for them. In general relativity, we experience gravitational time dilation. This means that time will run more slowly, the closer you are to a gravitating mass (such as the Earth). This is because, according to Einstein, everything moves through spacetime (the three spatial dimensions - length, width and height - plus Time) at the speed of light. If you are at rest in the three spatial dimensions, then you are moving through Time at the speed of light. If you begin to move through a spatial dimension, then Time slows down in order to keep your overall velocity below the universal speed limit of the speed of light. The Simpler Way A good way to think about it, is to scale it back to just two dimensions. Imagine that you are in a perfectly square car park measuring one mile by one mile. You are in a car that is limited to 30mph. If you drive straight across the car park at 30mph, a distance of one mile, it will take you 2 minutes. If, however, you drive diagonally from one corner to the opposite corner, it will take 2 minutes 49 seconds. This is because, in the first journey, you were only travelling through one axis, X. In the second journey, you were travelling through both the X and Y axes. Your speed is "shared" between all of the dimensions and so the faster you move in one dimension, the slower you move in another. So, scale this back up to four dimensions, if you move through the spatial dimensions at the speed of light, you are essentially "borrowing" that speed from your movement through the Time dimension.