8 Super Simple Ways To Explain Complicated Science

2. General Relativity = Think Of A Trampoline

The Tricky Bit General relativity is a geometric theory of gravitation, formulated by Einstein in the early 20th Century. According to GR, gravity is a geometric property of spacetime. The effects of gravity that we feel occur because objects with mass will bend and warp spacetime around them. This means that gravity is a disruption of the straight paths everything (including light) takes through spacetime causing them to "fall" towards a gravitating object. The effects of relativity predict all kinds of phenomena, such as black holes, time dilation, gravitational waves and gravitational lensing. The Simpler Way Although it's tempting to think of gravity as a force like magnetism that "pulls" you down to the Earth, it's much more accurate to say that you're actually falling towards the Earth due to the curve it creates in spacetime. A good way to visualise this is to imagine a trampoline. If you roll a ping pong ball across the trampoline, it will travel in a straight line to the other side. Now imagine placing a bowling ball in the middle of a trampoline. The bowling ball with not just sit on top of it, but will cause the trampoline to bend down towards it, creating a sort of well. If you then roll the ping pong ball across the trampoline again, it will fall towards the bowling ball if it passes through the gravity well. If the ping pong ball is travelling too slowly, it will fall right down to the bowling ball and come to rest on its surface. However, if it is travelling quickly enough, its path will curve around the gravity well and continue in a different direction. If the ping pong ball is travelling at exactly the right speed (and if we pretend friction isn't a thing), then it might fall towards the bowling ball at exactly the same speed that it is moving past it and will continue to go round and round. The ping pong ball is now in orbit.