702 INDEX
Electrodynamics (cont.)
energy
density, electromagnetic,
13,
20,
154; equation
of motion of
point
mass
in,
95-98;
field
equations
for
moving
media,
25-28, 51-56, 84-91,
515;
field
equations
for
resting
media, 15-24, 513;
field
equa-
tions for
vacuum,
9-12, 81-84, 147-154,
265n, 268n, 320-321;
field
measuring
instrument,
151, 154;
field
strength,
elec-
trical,
definition
of, 9;
field
strength,
magnetic,
definition
of, 9;
field
tensor,
electromagnetic, 81,
519n;
and
gravita-
tional
field,
124, 127,
147-154, 318-321;
Maxwell field
tensor, 22-24, 91-94, 264n,
266n, 269n,
567;
momentum
density,
elec-
tromagnetic, 14; stress-energy
tensor,
91-
94, 269n, 513, 517, 518
Electron,
15, 64, 116, 552; equation
of
motion
of, 98
Electron
theory,
Lorentz's,
3,
9-28,
29, 39,
51-56,
84, 153,
550n
Electrostatics,
22, 127, 194,
315, 488, 567;
Heaviside's electrostatic
unit,
9;
Poisson's
equation in,
397n
Emission,
induced
and
spontaneous
of radia-
tion, 113
Energy:
of
dipole, rotating,
273;
equipartition
theorem
of,
524;
inertia
of:
see
Mass-
energy equivalence;
kinetic,
138,
141-
142, 176, 307,
350, 522, 524-526, 530;
law
of conservation
of:
138, 140,
152,
258n,
521-523,
546,
613
(see
also
Energy-momentum,
law
of conservation
of),
in
special relativity, 64, 101;
mechan-
ical, 522, 533;
of
oscillator, 270-273,
275-284;
of
point
mass: see
Gravitation,
relativistic
theory of, dynamic
field,
Grav-
itation,
relativistic
theory
of,
static
field,
and
Relativity, special theory of; poten-
tial:
522, 533,
gravitational,
350; rest,
59,
108n,
569; thermal,
522,
563;
zero-point:
see
Zero-point energy
Energy-momentum,
law
of conservation
of:
of
matter,
198, 222n, 232n, 246,
311, 316,
476, 481, 488,
494, 574,
591, 595,
622n;
of
matter
and
gravitational
field,
318,
496,
567, 574, 580,
620;
and
perihelion,
439n,
441n; and
definition of
straight
line, 580.
See
also
Electrodynamics;
vector,
97,
249,
309, 569, 575
Energy
of
radiation,
absorbed
in
photochem-
ical reactions,
112, 121, 166;
Entropy:
Boltzmann
principle
for, 532,
562;
of diatomic
molecule, 280;
of
gas
mixture,
290;
gravitational potential
and,
155;
law
of increase
of, 561;
of
radiation,
118, 289;
at
zero
temperature,
558
'Entwurf'
theory
of
AE and
Marcel Gross-
mann,
294-301, 303-339, 344, 475, 491,
493, 495,
572,
576, 580-581, 585, 586,
589, 592, 596;
AE's later
comments on,
580-581.
See
also Gravitational
constant
Eötvös,
Roland
von
(1848-1919):
experi-
ments
on
equality
of inertial
and
gravitational mass,
304, 305, 478, 489,
493, 508,
585,
614,
621n
Equilibrium: dynamic, photochemical, 110;
improper thermodynamic, 109, 112,
115-
121, 121n,
166-169, 289;
proper
thermo-
dynamic, 288;
thermochemical,
290
Equinox,
vernal,
347-348
Equipartition
theorem of
energy,
524
Equivalence, principle
of. See
Principle
of
equivalence
Ether,
183,
536-541;
AE's
arguments against
hypothesis of,
539-541
Eucken,
Arnold
(1884-1950):
letter
to AE,
271; measurements
of
specific
heat of
hydrogen
by,
270-273, 278,
279,
553n,
554
Eulerian
angles,
355
Euler-Lagrange equations.
See Gravitation,
relativistic
theory
of,
dynamic
field,
Grav-
itation,
relativistic
theory of,
static
field,
and Perihelion
Euler's
generalized
hydrodynamic equations,
98-101,
517-519
Extremum
principle. See
Variational
princi-
ple
Faraday,
Michael
(1791-1867), 507,
510n
Faraday's
law
of electrochemical
equiva-
lence, 111
Faraday's
law
of
magnetic
induction,
11
Fekete,
Eugen
(Jenö) (1880-1943), 508
Fizeau's
experiment,
27-28,
34-36,
50,
104n,
183,
536-537,
545
Fluid, ideal, 100
Fokker,
Adriaan Daniel
(1887-1968),
273,