How To Understand Time Travel

Thursday, September 16, 2010

How To Understand Time Travel

Expand the description and view the text of the steps for this how-to video. Check out Howcast for other do-it-yourself videos from Phantasmic and more videos in the Out Of This World category. You can contribute too! Create your own DIY guide at www.howcast.com or produce your own Howcast spots with the Howcast Filmmakers Program at www.howcast.com Are you weirded out by wormholes? Flummoxed by your flux capacitor? Strap yourself in for this time-travel primer. To complete this How-To you will need: A basic knowledge of the theory of relativity An open mind A PhD in Physics (optional) Warning: Time-travel theories are riddled with paradoxes that may make your brain explode. Step 1: Understand "special relativity" Brush up on your Einstein: His special theory of relativity revolutionized physics by suggesting that traveling into the future is possible. The idea is that time slows down when you're traveling at high speeds relative to stationary objects. So if you're in a spaceship going very close to the speed of light for five years, you could return home to find that it's 50 years later on Earth. Tip: Even on a normal transatlantic flight, time slows down with speed. In one experiment using two atomic clocks, the clock sent into space fell 40 nanoseconds behind the one left on the ground. Step 2: Rule out traveling faster than light speed Going back in time is a far trickier proposition -- but might be possible if you could travel faster than the speed of light ...