INDEX 609
vection, 106, 107, 108;
electric
polarization, 46,
107,
108; density,
62,
266, 328;
energy,
98;
Foucault:
see
Fou-
cault
current;
and
magnetism, 145, 151,
173, 191; magnetic
convection,
107; mag-
netic
polarization, 107, 108, 109;
polarization,
definition
of,
46
Cylinder,
iron: for
measurement
of
Ampère’s
molecular
currents,
147, 155, 158, 165,
175, 179, 184, 192,
271, 272;
moment
of
inertia
of,
154,
160-161,
168, 175,
181,
187, 192,
273
Danziger, Jacques,
208,
210n
Darwin,
Charles
(1809-1882), 569;
evolu-
tionary theory
of, 509,
569
Davidson,
512
Debye,
Peter
(1884-1966), 35, 556;
on
quan-
tum state
of
macroscopic system,
33
De Donder,
Théophile
(1872-1957):
letter
from
AE,
346n
Degeneracy:
of
energy
states, 39n
De
Haas,
Wander
(1878-1960),
145, 148,
191, 193n,
271;
article with Geertruida
de
Haas-Lorentz,
149;
articles with AE
on
Ampère’s
molecular
currents,
145, 147,
151-169, 173-188, 231;
experiments
on
Ampère’s
molecular
currents, 147-148,
149,
155-165, 165-169, 175-176,
179-
188,
271;
letter from
AE, 148,
193n;
review
of
experimental
data
at
Third
Solvay Congress,
149
De Haas-Lorentz,
Geertruida
(1885-?):
arti-
cle with Wander de
Haas,
149;
letter from
AE, 148,
170n,
189n
Density:
continuous
mass
distribution,
102,
351;
electrical
charge,
61,
106, 107;
elec-
trical
current, 62, 266, 328;
electrical
rest,
62;
energy: 98, 355, 392, “complex” of,
9,
98-99,
100,
102-105,
117,
120, 414-415;
of
incompressible fluid, 326; magnetic
charge, 107;
matter,
in universe:
see
Uni-
verse,
matter
density in;
momentum,
98;
rest, 392;
radiation:
see
Radiation,
density
of
Descartes,
René
(1596-1650),
518, 519,
529,
533
De Sitter,
Willem
(1872-1934),
67n, 435,
545,
546;
AE’s
comments
on
article
by,
536n;
controversy
between AE
and, 552n;
correspondence
with
AE,
552n;
letter
from
AE, 18n,
357n;
letter
to
AE, 348,
352,
357n
Deutsche
Physikalische
Gesellschaft,
AE’s
lectures
to:
on
Ampère’s
molecular
cur-
rents,
145, 147,
151-169, 271-275;
on
Jacobi’s
theorem, 578n;
on
quantum
theo-
rem
of Sommerfeld and
Epstein,
556-566;
on
quantum theory,
30-38, 398n;
on
the-
ory
of Tetrode and
Sackur, 261n;
on
theory
of
water
waves
and of
flight,
402n
Dielectric:
constant,
107; moving,
48,
67n
Differential calculus,
7, 11,
55-61, 73,
77-
82,
87,
89-97, 111-112, 216-219, 227,
228, 246, 248, 284, 294-301, 379, 496;
three-dimensional,
55-58.
See
also
Christoffel, Elwin; Four-vector; Gauss,
Carl
Friedrich; Levi-Civita, Tullio;
Ricci(-Curbastro),
Gregorio;
Riemann,
Bernhard;
and Tensor
Differential
covariants,
theory
of, 17. See
also Differential calculus
Disk,
rotating,
477-480, 512-513, 537n;
cir-
cumference
of, 289-290, 338n,
479
Doppler
effect,
27,
55,
135,
391, 392, 458,
517, 526,
536n
Double
stars, 67n, 435
Dragging
coefficient.
See
Light, dragging
coefficient of
Droste,
Johannes
(1886-1963),
552n
Duck,
pregnant,
402n
Earth:
gravitational
field
of,
472
(see
also
Gravitational
field,
of
mass
point); mag-
netic field
of:
see
Magnetism,
terrestrial;
perihelion
motion
of,
242
Eclipse,
solar, 475, 511; in
1914,
24n; in
1919,
512,
537n
Eddington,
Arthur
(1882-1944), 512, 537n,
538n
Ehrenfest,
Paul
(1880-1933), 40n, 261n;
let-
ter
from
AE, 18n, 130n, 149,
261n, 338n,
380n, 416n, 536n, 552n, 567n;
letter from
Einstein, Elsa,
417
Ehrenfest’s adiabatic
theorem, 36-37, 39n
Ehrhardt, Paul, 402n;
letter from
AE,
402n;
letter
to
AE,
402n
Eichenwald’s
experiments, 48,
67n