INDEX
Aberration, 49
Absorption of energy, 46
Acceleration, 64, 67, 70
Action at a distance, 48
Addition of velocities, 16, 38
Adjacent points, 89
Aether, 52
—drift, 52, 53
Arbitrary substitutions, 98
Astronomy, 7, 102
Astronomical day, 11
Axioms, 2, 123
truth of, 2
Bachem, 131
Basis of theory, 44
"Being," 66, 108
β-rays, 50
Biology, 124
Cartesian system of co-ordinates, 7, 84, 122
Cathode rays, 50
Celestial mechanics, 105
Centrifugal force, 80, 130
Chest, 66
Classical mechanics, 9, 13, 14,
16, 30, 44, 71, 102, 103, 124
—truth of, 13
Clocks, 10, 23, 80, 81, 94, 95, 98-100, 102, 113, 129
—rate of, 129
Conception of mass, 45
—position, 6
Conservation of energy, 45, 101
—impulse, 101
—mass, 45, 47
Continuity, 95
Continuum, 55, 83
—two-dimensional, 94
—three-dimensional, 57
—four-dimensional, 89, 91, 92,
94, 122
—space-time, 78, 91-96
—Euclidean, 84, 86, 88, 92
—non-Euclidean, 86, 90
Co-ordinate differences, 92
—differentials, 92
—planes, 32
Cottingham, 128
Counter-Point, 112
Co-variant, 43
Crommelin, 128
Curvature of light-rays, 104, 127
space, 127
Curvilinear motion, 74
Cyanogen bands, 131
Darwinian theory, 124
Davidson, 128
Deductive thought, 123
Derivation of laws, 44
De Sitter, 17
Displacement of spectral lines,
104, 129
Distance (line-interval), 3, 5, 8,
28, 29, 84, 88, 109
—physical interpretation of, 5
—relativity of, 28
Doppler principle, 50
Double stars, 17
Eclipse of star, 17
Eddington, 104, 128
Electricity, 76
Electrodynamics, 13, 19, 41, 44,
76
Electromagnetic theory, 49
—waves, 63
Electron, 44, 50
—electrical masses of, 51
Electrostatics, 76
Elliptical space, 112
Empirical laws, 123
Encounter (space-time
coincidence), 95
Equivalent, 14
Euclidean geometry, 1, 2, 57,
82, 86, 88, 108, 109, 113, 122
—propositions of, 3, 8
Euclidean space, 57, 86, 122
Evershed, 131
Experience, 49, 60
Faraday, 48, 63
FitzGerald, 53
Fixed stars, 11
Fizeau, 39, 49, 51
—experiment of, 39
Frequency of atom, 131
Galilei, 11
—transformation, 33, 36, 38, 42,
52
Galileian system of co-ordinates,
11, 13, 14, 46, 79, 91, 98,
100
Gauss, 86, 87, 90
Gaussian co-ordinates, 88-90, 94,
96-100
General theory of relativity,
59-104, 97
Geometrical ideas, 2, 3
—propositions, 1
——truth of, 2-4
Gravitation, 64, 69, 78, 102
Gravitational field, 64, 67, 74,
77, 93, 98, 100, 101, 113
——potential of, 130, 131
Gravitational mass, 65, 68, 102
Grebe, 131
Group-density of stars, 106
Helmholtz, 108
Heuristic value of relativity,
42
Induction, 123
Inertia, 65
Inertial mass, 47, 65, 69, 101,
102
Instantaneous photograph
(snapshot), 117
Intensity of gravitational field,
106
Intuition, 123
Ions, 44
Kepler, 125
Kinetic energy, 45, 101
Lattice, 108
Law of inertia, 11, 61, 62, 98
Laws of Galilei-Newton, 13
—of Nature, 60, 71, 99
Leverrier, 103, 126
Light-signal, 33, 115, 118
Light-stimulus, 33
Limiting velocity (), 36, 37
Lines of force, 106
Lorentz, H. A., 19, 41, 44, 49,
50-53
—transformation, 33, 39, 42,
91, 97, 98, 115, 118, 119,
121
——(generalised), 120
Mach, E., 72
Magnetic field, 63
Manifold (see Continuum)
Mass of heavenly bodies, 132
Matter, 101
Maxwell, 41, 44, 48-50, 52
—fundamental equations, 46, 77
Measurement of length, 85
Measuring-rod, 5, 6, 28, 80, 81,
94, 100, 102, 111, 113,
117
Mercury, 103, 126
—orbit of, 103, 126
Michelson, 52-54
Minkowski, 55-57, 91, 122
Morley, 53, 54
Motion, 14, 60
—of heavenly bodies, 13, 15,
44, 102, 113
Newcomb, 126
Newton, 11, 72, 102, 105, 125
Newton's constant of,
gravitation, 131
—law of gravitation, 48, 80,
106, 124
—law of motion, 64
Non-Euclidean geometry, 108
Non-Galileian reference-bodies, 98
Non-uniform motion, 62
Optics, 13, 19, 44
Organ-pipe, note of, 14
Parabola, 9, 10
Path-curve, 10
Perihelion of Mercury, 124-126
Physics, 7
—of measurement, 7
Place specification, 5, 6
Plane, 1, 108, 109
Poincaré, 108
Point, 1
Point-mass, energy of, 45
Position, 9
Principle of relativity, 13-15,
19, 20, 60
Processes of Nature, 42
Propagation of light, 17, 19,
2, 32, 91, 119
——in liquid, 40
——in gravitational fields, 75
Quasi-Euclidean universe, 114
Quasi-spherical universe, 114
Radiation, 46
Radioactive substances, 50
Reference-body, 5, 7, 9-11, 18,
23, 25, 26, 37, 60
——rotating, 79
Reference-mollusk, 99-101
Relative position, 3
—velocity, 117
Rest, 14
Riemann, 86, 108, 111
Rotation, 81, 122
Schwarzschild, 131
Seconds-clock, 36
Seeliger, 105, 106
Simultaneity, 22, 24-26, 81
—relativity of, 26
Size-relations, 90
Solar eclipse, 75, 127, 128
Space, 9, 52, 55, 105
—conception of, 19
Space co-ordinates, 55, 81, 99
Space-interval, 30, 56
—point, 99
—two-dimensional, 108
—three-dimensional, 122
Special theory of relativity,
1-57, 20
Spherical surface, 109
—space, 111, 112
St. John, 131
Stellar universe, 106
—photographs, 128
Straight line, 1-3, 9, 10, 82, 88,
109
System of co-ordinates, 5, 10, 11
Terrestrial space, 15
Theory, 123
—truth of, 124
Three-dimensional, 55
Time, conception of, 19, 52,
105
—co-ordinate, 55, 99
—in Physics, 21, 98, 122
—of an event, 24, 26
Time-interval, 30, 56
Trajectory, 10
"Truth," 2
Uniform translation, 12, 59
Universe (World) structure of,
108, 113
—circumference of, 111
Universe elliptical, 112, 114
—Euclidean, 109, 111
—space expanse (radius) of,
114
—spherical, 111, 114
Value of , 82, 110
Velocity of light, 10, 17, 18, 76,
118
Venus, 126
Weight (heaviness), 65
World, 55, 56, 109, 122
World-point, 122
—radius, 112
—sphere, 110, 111
Zeeman, 41
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