Bantam has announced the publication date for Stephen Hawking's new book, The Grand Design. The Random House division will publish the book, which Hawking has co-written with Leonard Mlodinow, on September 7.

The book seeks to answer more questions about Hawking's core area of study, namely, how the universe began and how it works. Random House said the book examines the "unified theory," which is a single strain of thought that can explain all the forces of nature. The publisher said the book will look at such big-picture questions as 'Why do we exist?' 'Do we have free will?' and 'Did our universe need a creator?'