INDEX
217
- Identities connecting , 141
- Identity permanent, 40, 193
- Imaginary intervals, 150, 187
- Imaginary time, 48, 181
- Inertia, compared with force, 137; electrical theory of, 61; in regions at infinity, 157; infinite, 56; Mach's views, 164; of light, 110; relativity theory of, 139
- Inertia-gravitation, 137
- Inertial frame, 156
- Infinity, conditions at, 157
- Integrability of length and direction, 174
- Interval, 46, 150, 187; general expression for, 82; practical measurement of, 58, 75
- Interval-length, geometrical significance essential, 127; identified with proper time, 71; tracks of maximum, 70, 150; zero for velocity of light, 71
- Invariant mass, 145; of light, 148
- Jupiter, deflection of light by, 133
- Kaufmann's experiment, 62, 146
- Kinds of space, 81
- Laplace's equation, 96, 140
- Larmor, 19, 211
- Length, definition of, 2; effect of motion on, 19; relativity of, 34
- Le Verrier, 124
- Levi-Civita, 89
- Lift, accelerated, 64
- Light, bending of, 107, 112, 118, 207; coordinate velocity of, 107; mass of, 62, 110, 148; voyage round the world, 161; weight of, 111
- Light, velocity of, an absolute velocity, 59; importance of, 60; system moving with, 26, 56
- Lobatchewsky, 1, 9
- Lodge, 32, 125, 211
- Longest tracks, 70
- Lorentz, 19, 211
- Mach's philosophy, 163
- Macroscopic equations, 92, 139; interval, 187
- Map of sun's gravitational field, 99
- Mass, conservation of, 141, 195; electrical theory of, 61; gravitational, 98; identified with energy, 146; invariant, 145; of light, 62, 110, 148; variation with velocity, 145
- Mathematics, Russell's description of, 14
- Matter, continuous, 91; definition of a particle, 98; extensional relations of, 8; gravitational equations in, 141; perception of, 190; physical and psychological aspects, 192
- Mercury, perihelion of, 123, 125
- Mesh-systems, 77; irrelevance to laws of nature, 87
- Michelson-Morley experiment, 18
- Minkowski, 30, 212
- Mirror, distortion by moving, 22
- Momentum, conservation of, 141; re-definition of, 144; of light, 111
- Moon, motion of, 93, 134
- Motion, insufficiency of kinematical conception, 194; Newton's first law, 136
- Natural frame, 155
- Natural gauge, 176
- Natural geometry, 2
- Natural tracks, 70
- Nebulae, atomic vibrations in, 161
- Newton, absolute rotation, 41; bending of light, 110; law of gravitation, 93; law of motion, 136; relativity for uniform motion, 40; super-observer, 68
- Non-Euclidean geometry, 6, 73, 84, 90
- Non-Riemannian geometry, 169
- Observer, an unsymmetrical object, 57
- Observer and observed, 30
- Orbits under Einstein's law, 123
- Order and dimensions, 14, 186
- Ordering of events in external world, 35, 54, 184
- Past, absolute, 50
- Perceptions, as crude measures, 10, 15, 31
