The Meaning Of Relativity, by Albert Einstein
It’s a good thing this book has an introduction, because this particular work presents a bit of a conundrum for many readers, myself included. This short book, which including two appendices of some length comes out to only a bit more than 150 pages in length of Einstein’s material, finds itself in a bit of an uncanny valley as a work, but this is not necessarily a bad thing . Einstein, like a few of the great theoretical scientists of our time (Hawking comes to mind here), seeks to write in such a way that he can be understood by a wide audience, but this book is exceptionally technical and requires a great deal of familiarity with mathematics in order to understand. For example, it would be hard to get through much of this book sober if you played a drinking game that required drinking a shot every time that the word “tensor” was mentioned. That aside, though, this book is to be praised for the effort of its author in making the mathematics of special and general relativity accessible to a wide audience, even if this is a difficult book to understand. For those who are willing to take on the challenge of reading this book, though, there are some immensely useful lessons that can be gathered from Einstein’s approach.
In terms of its contents, this book is organized in a very straightforward and direct fashion, not wasting paper or the time of the reader, which is something to be appreciated. The introduction to the work provides the context of the work in discussing the problem that many people have in getting an intuitive feel for the world of relativity. After this the author discusses a look at space and time in pre-relativity physics, looking at what was thought to be constant. The author then looks at the theory of special relativity, spends a bit more time on the general theory of relativity in two chapters, and then writes two appendices that discuss some notes for the second edition as well as providing a rigorously mathematical relativistic theory for non-symmetric fields. One of the striking aspects of this book, aside from its sheer number of mathematical equations and the fact that the author seems to think that understanding what he is writing is a trivial and easy task, which is not the case, is the way that Einstein strives to work on setting boundary conditions and define as broadly as possible.
This is a notable trait that is worth pondering not just for theoretical physics but also in other areas of life. Much of the difficulty in understanding relativity and its implications is the fact that people tend not to be able to imagine very well, and theoretical physics definitely requires imagination in order to visualize. In reading this book it is clear that Einstein was able to live in a world governed by the Maxwell-Morey equations long before others did so, and his realization of their implications for classical physics gave him an advantage when it came to envisioning and describing and justifying a radically different conception of the world than the world of Newtonian physics that most of us tend to live and breathe in regardless of our knowledge of the physics developments of the last century or so. It is also clear that Einstein spent a lot of time trying to ponder the implications of his own work and make it as generally applicable as possible, while also reminding readers that without a constant one cannot make sense of a universe. That truth is an important one to remember, and it is unfortunately something that those who have misapplied relativity into relativism all too frequently forget.
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