The beginning of the 21st century is a watershed in modern science, a time that will forever change our understanding of the universe, Susskind contends. Several decades ago, he introduced the revolutionary concept of string theory to the world of physical science. In doing so, he inspired a generation of physicists who believed that the theory would uniquely predict the properties of our universe. Now, in his first book, Susskind argues that the very idea of such an "elegant theory" no longer suits our understanding of the universe, and that our narrow 20th-century view of a unique universe will have to give way to the much broader concept of a gigantic cosmic landscape--a megaverse, pregnant with new possibilities.--[Résumé de l'éditeur].