"Readers have repeatedly told Professor Hawking of their difficulty in understanding A Brief History of Time's most important concepts. This is the reason for A Briefer History of Time: the authors' wish to make its content more accessible as well as to bring it up-to-date with the latest scientific findings. Although this book is literally 'briefer', it actually expands on the great subjects of the original. Subjects of wide interest that were interspersed throughout the original have been given entire chapters including relativity, curved space and quantum theory. This reorganization allowed the authors to expand areas of special interest and recent progress, from the latest in string theory to exciting developments in the search for a complete unified theory of all the forces of physics. This edition will guide nonscientists everywhere in the ongoing search for the tantalizing secrets at the heart of time and space."