RELATIVITY
THE SPECIAL THE GENERAL THEORY
A POPULAR EXPOSITION BY ALBERT EINSTEIN, Ph.D.
PROFESSOR OF PHYSICS IN THE UNIVERSITY OF BERLIN AUTHORISED TRANSLATION BY ROBERT W. LAWSON, D.Sc. UNIVERSITY OF SHEFFIELD WITH FIVE DIAGRAMS AND A PORTRAIT OF THE AUTHOR THIRD EDITION METHUEN CO. LTD. 36 ESSEX STREET W.C. LONDON
This Translation was first Published August 19th 1920
Second Edition September 1920
Third Edition 1920
The present book is intended, as far as possible, to give an exact insight into the theory of Relativity to those readers who, from a general scientific and philosophical point of view, are interested in the theory, but who are not conversant with the mathematical apparatusThe mathematical fundaments of the special theory of relativity are to be found in the original papers of H. A. Lorentz, A. Einstein, H. Minkowski, published under the title Das Relativitätsprinzip (The Principle of Relativity) in B. G. Teubner's collection of monographs Fortschritte der mathematischen Wissenschaften (Advances in the Mathematical Sciences), also in M. Laue's exhaustive book Das Relativitätsprinzip–-published by Friedr. Vieweg Son, Braunschweig. The general theory of relativity, together with the necessary parts of the theory of invariants, is dealt with in the author's book Die Grundlagen der allgemeinen Relativitätstheorie (The Foundations of the General Theory of Relativity) Joh. Ambr. Barth, 1916; this book assumes some familiarity with the special theory of relativity. of theoretical physics. The work presumes a standard of education corresponding to that of a university matriculation examination, and, despite the shortness of the book, a fair amount of patience and force of will on the part of the reader. The author has spared himself no pains in his endeavour
to present the main ideas in the simplest and most intelligible form, and on the whole, in the sequence and connection in which they actually originated. In the interest of clearness, it appeared to me inevitable that I should repeat myself frequently, without paying the slightest attention to the elegance of the presentation. I adhered scrupulously to the precept of that brilliant theoretical physicist L. Boltzmann, according to whom matters of elegance ought to be left to the tailor and to the cobbler. I make no pretence of having withheld from the reader difficulties which are inherent to the subject. On the other hand, I have purposely treated the empirical physical foundations of the theory in a "step-motherly" fashion, so that readers unfamiliar with physics may not feel like the wanderer who was unable to see the forest for trees. May the book bring some one a few happy hours of suggestive thought!
[December, 1916]A. EINSTEIN
Note to the Third Edition