We all understand that the discovery of gravitational waves was a really big deal, but do you really understand what they are, why they're important, or how LIGO, the Laser Interferometer Gravitational Wave Observatory, found them? After watching this brilliant bit from the latest The Late Show with Stephen Colbert, you will. Theoretical physicist Brian Greene is also known for books such as The Elegant Universe where he explains concepts like string theory in layman's terms (Gizmodo spoke to him about it on an episode of Static podcast). He was on the show last night to give Stephen a crash course on not only why gravitational waves are important, but also how they were discovered.
Greene even goes so far as to break out a really neat experiment involving green lasers that replicates how the LIGO observatory works, but on a much simpler and smaller scale. If at the end of this clip you still can't wrap your head around gravitational waves, it's probably best to just leave that research to the professionals.