What If?: Serious Scientific Answers to Absurd Hypothetical Questions

From the creator of xkcd — serious, scientific answers to your most absurd hypothetical questions. What if you hit a baseball pitched at 90% the speed of light? How long would humanity last in a robot apocalypse? Randall Munroe runs the simulations, digs through declassified research and consults the experts, delivering answers that are equal parts hilarious and mind-expanding (and often end in a really big explosion). Illustrated with signature xkcd comics.