The Principle of Relativity THE PRINCIPLE OF RELATIVITY ORIGINAL PAPERS BY A. EINSTEIN AND H. MINKOWSKI TRANSLATED INTO ENGLISH BY M. N. SAHA AND S. N. BOSE LECTURERS ON PHYSICS AND APPLIED MATHEMATICS University College of Science, Calcutta University WITH A HISTORICAL INTRODUCTION BY P. C. MAHALANOBIS PROFESSOR OF PHYSICS, PRESIDENCY COLLEGE, CALCU. PUBLISHED BY THE UNIVERSITY OF CALCUTTA 1920 _Sole Agents_ R. CAMBRAY & CO. PRINTED BY ATULCHANDRA BHATTACHARYYA, AT THE CALCUTTA UNIVERSITY PRESS, SENATE HOUSE, CALCUTTA TABLE OF CONTENTS 1. Historical Introduction i-xxiii [By Mr. P. C. Mahalanobis.] 2. On the Electrodynamics of Moving Bodies 1-34 [Einstein’s first paper on the restricted Theory of Relativity, originally published in the Annalen der Physik in 1905. Translated from the original German by Dr. Meghnad Saha.] 3. Albrecht Einstein 35-39 [A short biographical note by Dr. Meghnad Saha.] 4. Principle of Relativity 1-52 [H. Minkowski’s original paper on the restricted Principle of Relativity first published in 1909. Translated from the original German by Dr. Meghnad Saha.] 5. Appendix to the above by H. Minkowski 53-88 [Translated by Dr. Meghnad Saha.] 6. The Generalised Principle of Relativity 89-163 [A. Einstein’s second paper on the Generalised Principle first published in 1916. Translated from the original German by Mr. Satyendranath Bose.] 7. Notes 165-185 Transcriber’s Note: The plain text version of this ebook includes complex mathematical formulas. Some are simple in-line expressions like k = 1 - 1/μ^2. They may include special notations such as x^y for x to the power of y, x_{y} for x with a subscript of y, [=a] for an 'a' with a bar across the top, [.a] for an 'a' with a dot over it, [..a] for an 'a' with two dots over it. Others are more complex “ASCII Art” like this: l l 2lc 2l t₁ = ------ + ------ = -------- = --- β² c - u c + u c² - u² c Some are so complex that they must be rendered in the TeX mathematical notation, enclosed between double dollar signs, like this: $$ \beta = (1 - \frac {u^2}{c^2})^{-\frac{1}{2}} $$ HISTORICAL INTRODUCTION