What remains when you eliminate all matter? Can empty space—a void—exist? Frank Close takes the reader on a lively and accessible tour through ancient ideas and cultural superstitions (including Aristotle, who insisted that the vacuum was impossible) to the frontiers of current scientific research. These newest discoveries tell us extraordinary things about the cosmos and may provide answers to some of our most fundamental questions: What lies outside the universe? If there was once nothing, then how did the universe begin?