What If?: Serious Scientific Answers to Absurd Hypothetical Questions

In 2005 Randall Munroe left NASA to create his immensely popular website XKCD known for its clever commentary on science romance sarcasm and language. The site now attracts between 600000 and a million page views each day. Occasionally Munroe received emails requesting his input on scientific debates. For instance one reader wrote “My friend and I were discussing what would happen if a bullet were struck by lightning and we thought you should settle it.” Enjoying these inquiries he decided to launch the series What If.