What are gravitational waves?

From PHD Comics, and explanation of what gravitational waves are and why their discovery is so important to the future of science. (via df)

Update: Brian Greene’s explanation of gravitational waves to Stephen Colbert is the best one yet:

Greene is great at explaining physics in terms almost anyone can understand. Even though it’s more than 15 years old now, his book, The Elegant Universe, still contains the best explanation of modern physics (quantum mechanics + relativity) I’ve ever read.

• books
• Brian Greene
• physics
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• Stephen Colbert
• The Elegant Universe
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