CONTENTS
[INTRODUCTION. By Professor H. H. Turner, F.R.S.]
[BIOGRAPHICAL NOTE]
SECT.
1. [THE SPECIAL THEORY OF RELATIVITY AS A STEPPING-STONE TO THE GENERAL THEORY OF RELATIVITY]
2. [TWO FUNDAMENTAL POSTULATES IN THE MATHEMATICAL FORMULATION OF PHYSICAL LAWS]
3. [CONCERNING THE FULFILMENT OF THE TWO POSTULATES]
(а) The line-element in the three-dimensional manifold of points in space, expressed in a form compatible with the two postulates
(b) The line-element in the four-dimensional manifold of space-time points, expressed in a form compatible with the two postulates
4. [THE DIFFICULTIES IN THE PRINCIPLES OF CLASSICAL MECHANICS]
5. [EINSTEIN'S THEORY OF GRAVITATION]
(a) The fundamental law of motion and the principle of equivalence of the new theory
(b) Retrospect
6. [THE VERIFICATION OF THE NEW THEORY BY ACTUAL EXPERIENCE]
[APPENDIX:]
Explanatory notes and bibliographical references
[ON THE THEORY OF RELATIVITY. By Henry L. Brose]
[SOME ASPECTS OF RELATIVITY. THE THIRD TEST. By Henry L. Brose]
[BIOGRAPHICAL NOTE]
Albert Einstein was born in March, 1879, the town Ulm, situated on the banks of the Danube in Würtemberg, Germany. He attended school at Munich, where he remained till his sixteenth year.
His university studies extended over the period 1896-1900 at Zürich, Switzerland. He became a citizen of Zürich in 1901. During the following seven years he filled the post of engineer in the Patent Office, Bern. He accepted a call to Zürich as Professor Extraordinarius in 1910, which he, however, soon resigned in favour of a permanent chair in Prague University. In 1911 he decided to accept a similar post in Zürich. Since 1914 he has continued his researches in Berlin as a member of the Berlin Academy of Sciences.
His most important achievements are:
1905. The Special Theory of Relativity.
The discovery that all forms of energy possess
inertia.
The law underlying the Brownian movement.
The Quantum-Law of the emission and absorption of light.
1907. The fundamental notions of the general theory of
relativity.
1912. The recognition of the non-Euclidean nature of
space-determination and its connection with
gravitation.
1915. Gravitational field equations.
Explanation of the motion of Mercury's perihelion.
[INTRODUCTION]
TOWARDS the end of 1915 Albert Einstein brought to its conclusion a theory of gravitation on the basis of a general principle of relativity of all motions. His object was to create not a visual picture of the action of an attractive force between bodies, but rather a mechanics of the motions of the bodies relative to one another under the influence of inertia and gravity. To attain this difficult goal, it is true, many time-honoured views had to be sacrificed, but as a reward a standpoint was reached which had long seemed the highest aim of all who had occupied their minds with theoretical physics. The fact that these sacrifices are demanded by the new theory must, indeed, inspire confidence in it. For the unsuccessful attempts that have been made during the last centuries to fit the doctrine of gravitation satisfactorily into the scheme of natural science necessarily lead to the conclusion that this would not be possible without giving up many deeply-rooted ideas. As a matter of fact, Einstein reverted to the foundation pillars of mechanics as starting-points on which to build his theory, and he did not satisfy himself by merely reforming the Newtonian law in order to establish a link with the more recent views.
To get at an understanding of Einstein's ideas, we must compare the fundamental point of view adopted by Einstein with that of classical mechanics. We then recognize that a logical development leads from "the special" principle of relativity to the general theory, and simultaneously to a theory of gravitation.