I've recently gone on a quest to update my knowledge (circa 1970 undergrad physics) of SpaceTime, Relativity, Quantum Mechanics, and Cosmology.  In doing so I've read, "Elegant Universe" and "the Fabric of the Cosmos" by Brian Greene and "Universe in a Nutshell" by Stephen Hawkins.<br><br>All of these works are excellent and have left me thinking 'WOW'. For days afterwards I keep thinking back and wondering ...<br><br>How can a quantum wave equation 'collapse' instantly through the universe when the particle it represents is 'detected' in one location?<br><br>What is the meaning of extra dimensions?<br><br>How do these new discoveries effect Theology?<br><br>Is the Entropy explanation the only reason that only Time in SpaceTime is uni-directional (fwd only)?<br><br>Etc Etc<br><br>Don't expect these works to sum up 'in a nutshell' - they fill one with awe and deep questions.<br><br>For my little brain, this has been a wonderful journey - opening up new worlds and, in particular, a new understanding of the Universe.  All three of these books have been superb travel guides.  My math is totally rusty but that was no detriment to reading either of these three as they do not depend on mathematical schema for there explanations.<br><br>However, I'll rank them:<br><br>5 stars to Fabric of Cosmos<br><br>4 stars to Elegant Universe<br><br>4 stars to Universe in a Nutshell.<br><br>Fabric is copyright 2006 and includes up to date (fall 2006) info in these rapidly advancing fields.  Fabric is more about SpaceTime than string theory predictions (or lack of predictions) regarding the fundamental matter and energy constituents of the Universe. IMHO Brian Greene does a much better job of proceeding sequentially through a topic than Stephen Hawkins.<br><br>Elegant Universe (as was his Discovery Channel series) very dependent on String Theory explanations, which is great if string theory proves to be correct, but doesn't quite cover the objections to string theory (which are many) or provide good coverage of alternate theories (see Hawkins books for that). Nevertheless it covers a modern understanding of the Universe and its constituents very well.<br><br>The same could be said for Stephen Hawkins in reverse - he doesn't support string theory but does support quantum electrodynamics. Often in reading 'Nutshell' I'd be brought up short by what, to me, was a jump in conclusions.  He doesn't lay down nearly the smooth explanatory path that Brian Greene does. So, from an understanding of Physics standpoint, I rate Elegant over Nutshell; but, Stephen Hawkins is a Nobel Laurate and sits on the Lucasian Chair at Cambridge (previously held by Newton and Dirac).  His 'A Brief History of Time" and "Universe in a Nutshell" are both fine reads, and have the added advantage of providing a glimpse into a great mind and personal stories describing some conflicts between physicists.<br><br>If your focus new discoveries about SpaceTime and the Universe - I'd go with Fabric.<br><br>If you interest is more towards the Universe and its fundamental constituents (especially as described by string theories) then  I'd go with Elegant Universe.<br><br>If you want both physics of the Universe and some insights into a great character - go with Nutshell.<br><br>I'm glad I've read all three! I'd especially recommend reading one each from Greene and Hawkins - their different view points highlight the very vigorous on-going debate on major issues.