Relativity: The Special and the General Theory

This paperback book is an attractive typesetting of einstein's original classic. However, we remind the buyer this paperback does not include the contributions of other authors in the hardback edition. Thus, the description and the search inside feature are somewhat misleading.

This is one of the slimmest books that I bought in 2001, bargain priced, and I was sure it could tell me a lot about myself as well as about how Einstein thought. I spent 1964 through 1967 studying the kind of mechanics which Einstein is thought to have expanded into another dimension by making time an axis which allows consideration of systems moving at different speeds. E=mc-squared was a formula that I knew from high school. When I was learning calculus at the University of Michigan in the fall of 1965, it seemed to be the perfect mathematics for expressing what happens to objects in motion. In algebra, the big problem for those of us with a one track mind, capable of being surprised by solutions which didn't actually fit the problem, was solving equations in ways which did not involve a solution that required dividing both sides of an equation by zero. In calculus, major trends were often considered much more important than minor trends when everything was divided by quantities that were so small, they were like numbers approaching zero, and borderline concepts were subject to the kind of ambivalence that makes borderline psychological experiences such a booming field in the area of personality disorders, but the key thing about this book is the attempt to keep an eye on what can be learned from science. I thought that I was picking up what still made sense to me in the U of M introduction to Physics until there was a question on the final exam which asked for a mathematical manipulation of equations to produce the result E = mc-squared. I knew some equations, and wrote a few things down, but I didn't come up with that answer. I think I even looked in the textbook after the test, to see if I had forgotten something which was on one page, but I couldn't find that page. This book has what I should have known then.The final section of the book, 7. AN ELEMENTARY DERIVATION OF THE EQUIVALENCE OF MASS AND ENERGY, from pages 70 to 73, claims to use the law of conservation of momentum, an expression for the pressure of radiation, and two coordinate systems, one of which is moving rapidly along the direction of the axis of a system which is fixed relative to a body that has equal radiation hitting it from both sides. I doubt if the professor for the Physics class expected me to think of this method of finding that E = mc-squared, and I'm still not sure that I believe this approach proves it. In the still system, the momentums of equal and opposite radiation complexes cancel each other completely, so the amount of energy which might be involved doesn't matter. For the system which is moving, the radiation is assumed to be hitting the body from some angle related to that speed, and the change of momentum added by the component along the axis of motion does not change the speed, so the additional momentum is considered an addition to the mass of the body. The mathematical solution depends on solving equations for the difference in the mass o

There is no doubt that Albert Einstein has been one of the most brilliant minds of the past century. His major contribution to science was the special and the general theory of relativity, which gave a new dimension to that we call today "Modern Physics". Many people feel frustrated because when they try to understand relativity, they find some authors that expound in their books a complex arrangement of equations referring to the mathematical part of the theory, namely, the books are accessible for people with certain levels of knowledge (that is the case of engineers, physicists, mathematicians, among others). Nevertheless, perceiving and anticipating this situation, Albert Einstein wrote this book (more than fifty years ago) whit the purpose of exposing the special and the general theory of relativity in such a way that anyone can understand it. I this sense, I think, Einstein succeeded because despite the shortness of the book, the same covers the most important aspects of relativity in a clear and concise form. Moreover, the book has appendixes where the author makes reference to some interesting subjects like the problem of space and relativity, the experimental confirmation of the theory, to name a few. If you have decided to learn something about relativity, and you do not have vast knowledge in physics and mathematics, I sincerely recommend you this book. On the other hand, if you were a reader looking for more technical information (mathematical foundation of general relativity), I would choose the book "Gravitation" written by Misner, Wheeler y Thorne. This text represents an encyclopedia about general relativity.

This is a superb introduction to Special Relativity, which this writer, who is certainly no genius, was able to work through at age 18 (not without effort). The material on General Relativity (GR) is no harder, but much less detailed, so that one cannot hope to get a realistic idea of what GR is really about from this book alone. In fact, one needs considerable preparation in Physics and Math to even begin to understand the nature of GR. Unfortunately, the quality of American education has deteriorated enormously over the past three decades, so that even the typical senior Physics major at all but a dozen or so American universities can no longer be expected to cope with this book. This book is a serious introduction and not meant for the present American high school graduate with A's in English but typically eighth-grade reading skills, and whose Math skills consist only of a few faint memories. Nor does the American university, which has responded to the lowering of standards in the high schools by continually lowering its own standards, prepare the student for books like this. Customers who whine that this book shows that Einstein couldn't write English betray not only their own very low reading level and poor preparation (the book requires nothing more than non-AP high-school Math and Physics), but also their foolishness in believing that Einstein, rather than a native speaker of English, prepared the translation into English. For the dedicated reader, for whom learning is a mission, and who has learned his high school Math and Physics, this is an excellent book. It gives the dedicated and prepared reader the chance to interact with one of the greatest minds of all time. Einstein himself believed that any high-school student would be able to read this book with understanding, a belief was shown to be wrong even in 1917. (A reporter in Berlin asked Einstein's niece, then a high-school student if she had read and understood the book. "Oh yes," she replied happily, "everything but the part about coordinate systems!") That this book has endured so long (more than eight decades) in popularity is a testament to the genius of its author and his ability to explain Physics clearly. This is a book which richly repays the effort taken to read it.