Before I read this book, I didn't know the first thing about string theory, general relativity or quantum mechanics. I believe people like me were the author's target audience; that is, people who are profoundly interested in the mysterious physics of the universe, but lack the scientific or mathematical background to understand them in their raw form. This book certainly shouldn't be seen as anything other than an introduction for those of us outside the field of physics.

Each chapter in this book lays down the foundation for the next chapter. Greene manages to group together scattered discoveries from the past century or so according to their relevance to the topic at hand, and it feels very natural. Every complex concept is explained in somewhat technical detail and then followed up immediately by a clever (and occasionally humorous) analogy. The key points are always restated and rephrased to make absolutely sure the reader is on the same page with the author. This method really does wonders for nailing important concepts to your head, which turns out to be absolutely essential as the book progresses and new ideas are stacked atop the old.

This book, overall, is interesting. There are some extraordinarily intriguing chapters that will have your mind racing for at least a couple days, trying to piece together the chapter's implications, and then there are a couple dull chapters that almost feel like a chore to get through. However, the dull chapters, which seem to be flooded with basic mathematical and technical details, are necessary to understand the big picture. Greene only presents us with the details we need to understand, nothing more, and I honestly can't think of a way he could have made these dull chapters exciting.

If you are a curious physics newbie, or only know bits and pieces about the basic concepts of string theory, special and general relativity, quantum mechanics, black holes, the big bang, or hidden dimensions, this book is certainly for you! If you are already knowledgeable in these subjects and seek the deepest technical and mathematical information about them, I'm guessing you will not find what you are looking for in this book.

  I had picked this book up in its hardcover edition a few years ago, but haven't got around to reading it until recently and I'm sorry I didn't do so earlier.It is an excellent introduction to physics and an outstanding overview of "string theory" that is accessible to the layman (in as much as particle physics *can* be accessible without a real knowledge of mathematics.)

The Elegant Universe is worth the purchase price, if only for chapters 2,3 and 4 which lay out, in terms understandable by anyone, the ideas behind Einstein's theory of special relativity, Einstein's theory of general relativity and quantum mechanics.I highly recommend it for this purpose alone.

The rest of the book deals with the central connudrum of modern physics which is, unfortunately, although the theories of relativity (governing large systems) and quantum mechanics (governing minute systems) have been experimentally verified over the past century and are indeed true, they are *not compatible*.Greene does a good job of explaining why the theories are in conflict with one another.

The rest of the book deals with string theory, which Greene and a lot of other string theorists claim can "bridge the gap" between relativity and quantum mechanics.Although Greene does a terrific job of explaining string theory through graspable metaphors, towards the end end of the book, my tiny brain had difficulty understanding some of the concepts.

Yet, by far, Greene provides the most accessible description of this revolution in physics.Greene is quite obviously an ardent evangelist of string theory and his optimism concerning its possibilities lend a certain energy to the read, getting you through the difficult parts.You can tell that this is a man who loves and is excited by what he does for a living, and that excitement is contagious.

Anyone with an interest in why the universe is the way it is will be well rewarded by this text.

Brian Greene's "The Elegant Universe" is the best book on a scientific subject I've ever read.The first five chapters, which deal with Space, Time, Special & General Relativity, and Quantum Mechanics, are incredibly clear and worth the price of the book alone.Without using any math, Greene is able to explain the key points of all these topics, and most importantly, to show why Relativity and Quantum Mechanics are incompatible, and why that's a problem for physicists.He then takes the reader through the various stages of thinking that have gone into String Theory, and it's fascinating stuff!Greene uses copious examples to demonstrate concepts that are difficult to visualize or grasp, and this is incredibly helpful.You definitely get a sense, for instance, of what a "curled up dimension" means, through some very clever reduced-dimension examples (not sure if these are Greene's constructions or well-known in the physics world, but they're very clear and helpful).The going gets a little tougher towards the endof the book, where the most recent thinking on String Theory and the discussion of Black Holes & the early instants of the cosmos are more complex and tougher to grok straight through.But even so, they are fascinating and worth the effort.

Greene's prose is clear, analytical, and well thought out.At least a half dozen times while reading the book, I said to myself, "Hmmm, but what about X?" to find a few paragraphs later Greene would write,"You may be wondering about X.Well, here's how that works..." To me, this is a sign of a clear thinker and helped make the book even more enjoyable to read.If you're at all interested in cutting edge physics theory, this is a great book to turn to.

  This is an excellent trip through the wonders of modern cosmology and physics. I kept having to get up and walk around the room once in a while and pinch myself to get a new reality fix. Well maybe reality -- but Mr.Greene might think I was fooling myself and only moving about in the 3dimensional space known to my conciousness, and not the other seven tightlywrapped dimensions in Calabi-Yau forms at a billionth of a billonth of ameter. Who needs science fiction when the real thing is so"unreal?"

As a reader I have more than a casual interest inmodern physics and have read dozens of books in this vein, however I do nothave a math background sufficient enough to deal with the professionalliterature in the field. I have found this work one of the best inexplaining string theory. Mr. Greene's approach of using analogy andmetaphor is right on target. His sometimes humorous approach was a goodantidote for what could become overbearingly theoretical.

The first halfwent down pretty easily in spite of the difficult nature of the subject.Brian Greene deserves much applause for pulling off this bit of magic. Thesecond half gets tangled up in the author's own areas of research and Ifelt that he suddenly began talking to a different audience, in this casehis peers, and instead of an explanatory tone, the book seemed a little bitargumentative. Of course this is a topic where anything said in adefinitive manner is likely to provoke a professional argument.Nonetheless, the first half of the book is well worth the read and morethan adequately covers the field for the reader where this topic would beof interest. The second half will be of interest to folks with morebackground.

In this book on eleven-dimensional space-time, Brian Greene proves himself to be truly exceptional in at least three of those dimensions:by his thorough comprehension of the origins and direction of theoretical physicsup through the emergence of superstring theory, by his monumentalcontributions to that theory in identifying its components and extendingits reach, and, thirdly, in explaining this subject in a way that allowsthe "layman" to gain an appreciation and intuitive understanding ofit.

By way of explaining the use of the term "layman," let me point outthat this book is not light reading.I don't believe it can be read bythose without at least some exposure to college level physics.I am aformer high school physics teacher, and I had to really stretch tounderstand Dr. Greene's explanations.Nevertheless, considering themathematical and physical complexity of the subject matter, Dr. Greene hasdone a splendid and remarkable job of explaining the subject at aconceptual, nonmathematical level. Anyone with a physics background throughthe level of an introductory course in modern physics will find Dr.Greene's treatise accessible.It brings the reader closer to the currentstate of research in the rapidly moving field of superstring theory thanbooks written even two years ago.

The book requires work, but it wasa labor of love.This book is beautifully and artfully written and was ajoy to read.I recommend it highly to anyone with the modest physicsbackground described above who enjoys exploring theoretical physics andcosmology at a level approximating that of Scientific American.