‘EINSTEIN AND THE UNIVERSE: A POPULAR EXPOSITION OF THE FAMOUS THEORY’ by CHARLES NORDMANN, translated by JOSEPH McCABE, begins with a summary of the difficulties in following the wonderful treatise of Einstein. As he puts eloquently, ‘frightful monsters, sometimes rectangular and sometimes curvilinear, which are known as "co-ordinates, are always there for us to see." They bear names as frightful as themselves "contra-variant and covariant vectors, tensors, scalars, determinants, orthogonal vectors, etc. These strange beings, brought from the wildest depths of the mathematical jungle, join together or part from each other with a remarkable promiscuity, by means of some astonishing surgery which is called integration and differentiation. Einstein may be a treasure, but there is a fearsome troop of mathematical reptiles keeping inquisitive folk away from it”. Hence the author has chosen to drive with the whip of simple terminology, and approach the splendor of Einstein's theory.
As promised, this book is a whiff of fresh air, in the deep jungle of relativity; more appealing as the author has carefully guided his wonderful dissertation away from all such apparitions, and other impediments to easy learning. He begins with interesting historical anecdotes and foundations laid by many forerunners of the great scientist. It begins with Poincare, who in any case, is the leader of those who regard space as a mere property which we ascribe to objects. If some malicious spirit were to amuse itself some night by making all the phenomena of the universe a thousand times slower, we should not, when we awake, have any means of detecting the change. The world would seem to us un- changed. How, out of the contradiction of the ethers behavior, this conflict of two irreconcilable yet indubitable facts, Einstein's splendid synthesis, like a spark of light issuing from the clash of flint and steel, came into being, is explained in the chapter, Einstein’s solution.
In the chapter Einstein’s mechanics, the book tells how Einstein's theory, as a direct effect of what it teaches in regard to space and time, completely upsets the classical mechanics. While introducing the discussions on the flow of time, the author, by giving the example of an observer, who while receding from the earth at a speed greater than that of light, sees terrestrial events happening as if he were ascending the stream of time, makes the whole topic remarkably succinct. How the velocities are not added together in equal proportions and indefinitely for a given observer, as classical mechanics maintained. How mass increases with velocity. How gravitation is not a force, as Newton thought, but simply a property of space in which bodies move freely. How every moving body freely left to itself in the universe describes a geodetic, are only some of the other challenges taken head on. A brief historical background is added to each and every concept when introduced fresh, making the flow of new ideas smooth and breakfree.
The author deserves special credit for making the subject amply clear without needing the help of complex equations or symbols. I always wanted to read a book like this. Learn happily the challenging concepts of relativity, space and time. Put to rest, threats from mathematical monsters.