1 stars (Who is the audience for this book?) - This is the first review I have been moved to write ... I bought this book because I like to read other people's perspectives on Physics; particularly when they are as smart as Roger Penrose undoutedly is. I have a PhD in theoretical physics (QFT) so I am hardly uneducated, or uninterested, in these topics. I found that this book tried to jump straight to an elegant mathermatical explanation without trying to impart any of the physical understanding. If you don't already know this material, this book won't help. At several points I just laughed out loud; one in particular when after explaining some arcane point in complex algebra involving a fraction, Penrose adds a comment along the lines of "I explained what a fraction was at the start of the book". He seems to be under the total delusion that you can just present the results of 20yrs of education in as many pages and people will just pick it up. I can only conclude that he is so familiar with this material that he has completely lost touch with its difficulty. The same must be said for those reviewers who liked this book; or else they are just lying to make themselves feel good; or perhaps they don't understand as much as they think they do! 5 stars (Shining brilliance!) - Penrose's book is really a thrilling experience. His intuition is brilliant. His explanations are crisp. His teaching ability can be probably only matched by Feynman. I got the book yesterday, but couldn't stop reading it so far. The first 150 pages I've read gave me a completely new perspective on complex calculus, which I had studied in undergraduate and thought I understood it. I am looking forward to other sections on differential geometry and other advanced topics. The book is very appropriate for people who have taken/are taking math courses but don't have good intuitive feel for the subjects covered---most math courses (especially, the grad ones) only emphasize the mathematics not the in... Knopf :: Science & Astrophysics & Space Science :: Science&Mathematics :: Science :: Physical laws :: Mathematical Physics :: General :: Cosmology :: Astrophysics & Space Sc :: The Road to Reality - A Complete Guide to the Laws of the Universe