Rating: Summary: A theory of everything (TOE) Review: Matter, we all know, consists of atoms, which consist of a nucleus of protons and neutrons surrounded by a mist of electrons. Protons and neutrons are made of quarks. The fundamental particles in the standard theory are organized in three families. The first family consists of the familiar electron, electron neutrino, the up quark, and the down quark. The other families contain similar particles, having identical electrical, weak, and strong charges, but having different masses. There are also particles for the strong force (gluon), electromagnetic force (photon), weak force (weak gauge bosons) and gravity (graviton).String theory tells us that these fundamental particles are not really so fundamental after all. Instead, the vibrations of a tiny one-dimensional loop of string within define the physical properties of each of the fundamental "According to string theory, the properties of an elementary "particle" - its mass and its various force charges - are determined by the precise resonant pattern of vibrations that its internal string executes." There are no known experimental circumstances in which the standard theory disagrees with experiments in quantum mechanics. Similarly, there is no known experimental circumstance in which the general theory of relativity conflicts with measurements in the cosmos. Yet scientists realize that these theories - successful as they are - cannot be complete because they are mutually inconsistent. Before superstring theory, however, all attempts to reconcile the general theory of relativity on a quantum scale have failed. This is the impetus for the search for the "theory of everything," or TOE, and it is the subject of Brian Greene's book. Greene begins with a high-level summary of string theory, encapsulating the essential elements of the theory in the idea that the resonant patterns and energy of string filaments within define fundamental particles. He then outlines the problems between the general theory of relativity and quantum mechanics, which is the driving force behind the quest for a unified theory. In laying this foundation he gives crisp and clear descriptions of the ideas in relativity as they pertain to time and space - showing how Einstein turned our past notions of these things upside down. Next, Greene describes quantum weirdness, and how quantum theory, like relativity, attacks our sensibilities and intuition. There are the usual discussions of the double-slit experiment along with a brief discussion of Feynman's formulation of quantum mechanics in which particles are viewed as traveling along every possible path through space and time and engaging in the weirdness of self-interference. With the essential ideas in quantum physics and general relativity established, Greene shows how these theories - successful as they are - cannot be complete because each is incompatible with the other in its own sphere of influence. Greene then makes the critical case for string theory. Among his repertoire of evidence, the most commonly cited are aspects of symmetry and beauty. Unlike the standard theory, string theory does not dabble in tables of measured data, which are then incorporated into the theory. The standard model is impressive, but not until you first measure the charges and masses of the fundamental particles. String theory, on the other hand, is "unique and inflexible .... It requires no input beyond a single number ... [and] all properties of the microworld are within the realm of its explanatory power." The real problem with the theory is that it is so mathematically intense that nobody can solve the theory's equations exactly. In fact, it's so difficult that only approximations for the equations are known - even the exact equations have proven elusive thus far. This makes it hard to press the case for superstring theory. Greene Signatures") devoted to physical evidence in support of the theory, but the evidence so far is pretty thin. Among the most encouraging results is the fact that superstring theory requires the graviton. In principle, superstring theory can be used to calculate the masses and electric charges of the fundamental particles, but so far the mathematics has proven intractable. Much of the book deals with the mathematical issues that are blocking present progress (though in a strictly quantitative fashion - there are no equations). There are some good discussions about higher dimensions (superstring theory demands them) and the warping of space. I found the discussion of M-theory especially interesting. You see, there are several superstring theories, and M-theory explains how they are really all just different manifestations of the same. About 2/3 of the book deals with historical backgrounds in general relativity, the standard model, and developments in superstring theory. I expected more subject matter on cosmology, but that's okay. The book is great as written. There is a chapter on black holes and how superstring theory helps us understand them better. There is also a chapter on cosmology and implications for superstring there. Among other things, superstring theory helps us deal with the problems of a mathematical singularity in the explanation of the big bang, but the jury is still out on superstring theory and singularities in black holes. The book ends with a chapter on future prospects, and it has a very useful section containing endnotes for the various chapters (I highly recommend reading the endnotes). To top it off, there is a wonderfully useful index, and the figures are all nicely done (though I would have included more figures - that's my only complaint). This is a wonderful book. It's written at an intelligent level, but does not burden the reader with the almost intractable mathematics of string theory. Greene has done a masterful job of explaining in clearly illuminated terms the ideas of what may be the most important theoretical study of the next century. If you enjoy intellectual stimulation and thoughts that will make your head swim, then this is a book you really must read. Duwayne Anderson, February 03, 2000
Rating: Summary: Surprisingly Understandable Review: With absolutely no background in physics, I was afraid that I would be lost soon after beginning but I have been pleasantly surprised. Greene gives an easy to understand example for each concept as he introduces it. He makes the concepts, at least on a broad base, accessible for everyone. In a pleasant writing style, Green takes the reader through the beginning theories of Newton and explains Einstein's Special and General Theories of Relativity - illuminating the rift between the micro and macro trains of thought. Once the reader is brought up to speed about the current question in physics, Greene explains patiently and carefully the concepts being dealt with and proposed by the Unified String Theory. If the last time you read anything about science was sixth grade, this is an excellent book to help you attempt to "be informed".
Rating: Summary: Absolutely Superb and magnificent Review: If you're looking for a book that explains the most abstract and intangible physics theories in a down to earth manner, look no further. The author uses day-to-day analogies to illustrate his points. He has a very elaborate writing and excellent vocabulary. You won't be dissapointed, not a single bit. This book is suitable for both the experts and the begginers as well. He skips some mathematical concepts in order to not get the reader confused with unnesessary [unless you are a science major] calculations that can make an average person put the book down. Again, this book is a MUST if you're interested in theoretical physics.
Rating: Summary: Sagan plus some Review: This is a truly spectacular tour de force through modern-day physics. If Carl Sagan's writings excite you, but you want to get more in-depth, hurry, hurry, hurry and buy this book. Through the liberal use of down to earth metaphors, Greene brings the obscurity of the concepts of quantum mechanics and more into clear focus. But be forewarned - your head will swim more than once while reading this book. Greene himself will warn you at times that if you are not dizzy from the concept, you're not getting it. This book is not for everyone - amateur scientists will appreciate it the most. If you are of that mind, then I think you will, like me, walk away from this book full of renewed awe and wonder at the world around us.
Rating: Summary: Really,really hard concepts made fun! Review: I've met the Author after a lecture and book signing at the Fermi Labs in Illinois. As a speaker,writer and physicist he is brilliant. He can convey his point without relying on overly complex mathamatics and even adds a sense of fun and discovery to his writings. This is one of the rare books that works for the highly advanced specialist as well as the casual backyard science enthusiast. If you only read one book about super strings this year, this should be it!
Rating: Summary: Changes the way you see the world Review: If you have an interest in physics, but don't have a good background in the subject, this book is a great read. It is very well written and understandable. Greene uses well constructed examples that are easy to understand and keep the book moving. I found that after reading this I really didn't look at the world in the same way -- but I guess it is fair to say that could be say after absorbing many other physics books. On the down side (other reviews have mentioned this), I found the book a bit pedantic at times, but it is a great work regardless.
Rating: Summary: The new String Theory...a breathtaking view of our Universe Review: This young author and physics professor possesses a towering grasp of our universe coupled with a gift for language. He makes an intensely complex subject understandable and exciting to read about. It's too early to tell if this fine book will make the N. Y. Times best-seller list, but it is most deserving. Over the last half-century scientists have made great strides uncovering the mysteries of the universe. The universe has two foundational pillars: One is Einstein's theory of relativity, which provides a framework for under-standing the universe. The other is atoms and subatomic particles like elec-trons and quarks. But the two "big" and "small" theories don't fit together. The new superstring theory (referred to as "the string theory") puts these two structures together and comes up with a plausible explanation of all matter. This new hypothesis has, to date, withstood extensive testing. Now, physicists have probed deeply into the structure of matter to show that everything in the universe, big and small, is some combination of quarks, electrons, or nutrinos. Did this occur by chance, divine choice, or is there a scientific explanation? We don't know, but the string theory comes closest yet. It is possibly the "theory of everything" (TOE). It follows that if you understand everything about the ingredients of something, you understand everything. Now, we understand that if anything like the string theory is correct, our universe has properties that would have dazzled even Einstein. This new theory destroys old concepts. For example, it dictates that there is no time or distance. The feeling of space is in the eye of the beholder; it depends upon where you are and where somebody or something else is. But the "big bang" theory of the universe fits the string theory, which holds that the universe came to being from compressed energy the size of a grain of sand. So it appears at last we have a unified theory of matter and force that makes up our universe. It derives from minute, oscillating pieces of string which, by the way, communicate with each other. And there is no time, nor space. Maybe our universe is merely a frothing bubble on a vast cosmic ocean aptly named "multi-universe." The author modestly concludes though: "As we (scientists) collectively scale the mountains of explanation, each generation climbs a little higher." This imaginative, interpretive book is for those with a scientific turn of mind and a good feeling for math and physics. It offers a breathtaking view of our universe.
Rating: Summary: Who is this guy? Review: Greene makes some good points the main one being that strings are interesting(the best example being the calculation of black hole entropy) despite the lack of experimental evidence.For a layman such as myself, it was quite accessible. My only complaint is that the book seems a little biased towards the work of Greene himself. I have no reliable method of estimating his contribution but, judging from the book, it was him, Witten and a few others who made the field. Witten I believe.
Rating: Summary: Arm Chair Physics Review: If you are an arm chair physicist as I am, this book is for you. In a field of knowledge that is constantly evolving, Mr. Greene calmly takes us by the hand and walks us through the history of physical thought, in an attempt to prepare us for the latest, seemingly outrageous in theoretical physics. In this, he succeeds. Concepts from Newton's Classical Physical Laws, through Einstein's Relativity and Bohr's Quantam Theory are revisited as Mr. Greene takes the time to allow us to share in the brilliance of these important, life changing breakthroughs. His use of character driven metaphors as examples of each of these schools of thought bring us to an immediate understanding of their underlying principles. You will learn something here. After this well thought out primer, the second half of the book introduces us to the latest innovations in physics, namely string theory. He points out the reliance of this theory on some rather esoteric mathmatics, and as such, string theory is a bit more difficult to relate to. If one continues the walk, however, you will be introduced to such bizzare concepts as a ten dimensional universe, and two dimensional loops being the basis of all matter, defined only by their vibrations. This is journey worth taking, though you may have to slow down to a crawl at times. In the end though, the universe won't ever seem quite the same.
Rating: Summary: Excellent Book Review: Assumes no prior knowledge of physics as such. Has an excellent introduction to relativity and quantum theory. Actually, I haven't seen a better introduction to relativity or quantum theory elsewhere. The book then moves on to string theory (which is the main theme of the book). An excellent introduction to string theory, I must say. The book is very easy to follow and can very well serve as a layman's introduction to high-end physics. For the more advanced readers, the author provides endnotes which elaborate the subject matter in a mathematical/physical perspective. People from all walks of life will enjoy this book
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