text: Eighteen-year-old student Ryan Chester won US$400,000 back in 2015 for this video explaining Einstein's Special Theory of Relativity, as part of the inaugural Breakthrough Junior Challenge - an international competition that aims to inspire the next generation of scientists and science communicators.
  And it's not hard to see why. If you heard the words, "Einstein's Special Theory of--" and tuned out because it's all too hard, we have a feeling Ryan will change your mind.
  The Special Theory of Relativity, which Einstein published in 1905, is made up of two postulates:
  1. The Principle of Relativity: This states that the laws of physics are the same in all inertial reference frames. Put another way, places that are moving at constant speeds relative to each other are governed by the exact same laws of physics, whether they're moving at 10 or 10 million km/h.
  2. The Principle of the Constancy of the Speed of Light: This states that the speed of light in a vacuum has the same value (physicists use "c" as the value), in all inertial frames, regardless of how fast the observer or light source are travelling. Or, as Clinton Nguyen puts it over at Motherboard, "Why faster-moving objects seem to age slower from a slower observer's point-of-view."
  Chester tackles the first postulate using a chair, a box, and a huge bowl of popcorn. He shows that when he sets everything up in his backyard and sits himself down in front of the popcorn, nothing happens.
  Earth might be spinning at about 1,675 kilometres per hour (1,040 mph), but so are both Ryan and the bowl of popcorn, so it appears as if everything is staying still.
  Things change when Ryan moves to scenario to a moving car.
  At first, everything behaves just as it did in the backyard - Ryan and the bowl of popcorn are steady in their positions because everything is moving at the same constant speed. As soon as the car speeds up? Well, let's just say things get a little messy.
  In the video, Ryan explains how that proves the first postulate of the Special Theory of Relativity. But what about the second postulate?
  First, the video gives us some background into the concept of the ether - a hypothetical medium proposed in the 1800s through which light waves travel. It was thought that because sound waves need a medium to travel through, so too does light.
  Of course, Einstein managed to prove that this ether doesn't actually exist, and went on to prove that light waves in a vacuum will have the same value c, regardless of the speed of the source of the light.
  I'll let Ryan explain the very complicated but amazing relationship between the speed of light and time dilation to you in his awesome video above, but all I can say is prepare to feel very, very smart when this is all over.
  For his efforts, Ryan's earned a scholarship of between US$400,000 and $250,000, with $50,000 going to his teacher, and $100,000 to his school, so they could build a new science lab. He managed to top 2,000 other applicants and 15 finalists to snag the prize.
  What an absolute hero. We have a feeling this isn't the last we're going to see of Ryan Chester and his amazing talent at communicating science, and that just made our day.
  A version of this article was first published in November 2015.