Arthur Stanley Eddington

“ In the case of a star seen behind the sun the added divergence has no time to take effect; but when the light has to travel a stellar distance after the divergence is produced, it becomes weakened by it. ”

“ It is found that the following scheme of potentials rigorously satisfies the equations , according to the values of in Note 5, where and is any constant (see Report, § 28) . Hence these potentials describe a kind of space-time which can occur in nature referred to a possible mesh-system. If , the potentials reduce to those for flat space-time referred to polar coordinates; and, since in the applications required will always be extremely small, our coordinates can scarcely be distinguished from polar coordinates. ”

“ These experiments were first-order experiments, i.e they depended on the ratio of the velocity of the transparent body to the velocity of light. The Michelson-Morley experiment is the first example of an experiment delicate enough to detect second-order effects, depending on the square of the above ratio; the result, that no current of aether past terrestrial objects could be detected, appeared favourable to the view that the aether must be convected by the earth. ”

“ It is not possible to predict the contraction rigorously from the universally accepted electromagnetic equations, because these do not cover the whole ground. There must be other forces or conditions which govern the form and size of an electron; under electromagnetic forces alone it would expand indefinitely. ”

“ Lobatchewskian, 1, 9; natural, 2; non-Euclidean, or Riemannian, 6, 73, 84, 90; non-Riemannian, 169; semi-Euclidean, 47 Ghosts of stars, 161 Globe of water, limit to size of, 148 Gravitation, Einstein's law of, differential formula, 90; integrated formula for a particle, 97; macroscopic equations, 140, 193 Gravitation, Newton's law of, ambiguity of, 93; approximation to Einstein's law, 103; deflection of light, 109, 111 Gravitation, propagation with velocity of light, 94, 147; relativity for uniform motion, 21, 125 Gravitational field of Sun, 97 ”

“ Davidson, 114 Deflection of light, effect on star's position, 112; observational results, 118; theory of, 107,207 Density, effect of motion on, 62 Displacement of spectral lines, 129; in nebulae, 161 ; in stars, 135 Displacement of star-images, 112, 115 Double stars and Einstein effect, 133 Duration, not inherent in external world, 34 Eclipse, observations during, 113 Ehrenfest's paradox, 75 Electrical theory of inertia, 61 Electricity and gravitation, 167 Electromagnetic potentials and forces, 172 Electron, dimensions of, 177; geometry inside, 91; gravitational mass of, 178 ”

“ Causality, law of, 156 Causation and free will, 51 Centrifugal Force, compared with gravitation, 41, 65; debt at infinity, 157; not caused by stars, 153; vibrating atom in field of, 129 Chess, analogy of, 184 Christoffel, 89 Circle in non-Euclidean space, 104 Clifford, 77, 152, 192 Cliquishness, 188 Clock, affected by velocity, 58; on sun, 74, 128; perfect, 13; recording proper- time, 71 Clock-scale, 58 Clock-scale geometry, not fundamental, 73, 131, 191 Coincidences, 87 Comets, motion through coronal medium, 121 ”