aia 
The lower limit of the last integral has been so chosen that at 
infinity we have y= 0. 
Put now 
r 
dar fir aA" (*) | odr == nln): 24. nl B aN, 
U 
R being the sun’s radius. Then, since for 7 > F (i.e. outside the 
sun) o = 0, we find 
ai 2 
A 2A,* 
Y= MN + mr)? + 2, [n(r) - NJ]... (18) 
(on 
r 
These formulae ean be used both inside and outside the sun, if 
we neglect the strains and pressures caused by gravitation inside 
the sun. Outside we have 7 (r) = N, and m'(7) and m/(r) are constants. 
Since the difference m’ -m is of the order of 2?,, we can in the 
term which has 4‘, as a factor use m’ instead of m. If now we put 
k? im’ 
c? 
Aiea, DES 
then the formulae outside the sun become 
TO EV ad 
Re hl 
14 
AAL DAS i 
| 
ge ed 
The quantity 22°, which corresponds to ErnsrerrnN’s a, has the dimen- 
sion of a length. For the sun its value is 2.945 km; for an atom of 
‘hydrogen 510-48 microns. For r= 2/? we have y'=0. The 
remarkable consequences of this fact have been very completely 
investigated by Droste. In actual problems r is always very much 
larger’) than 22°. 
The values of g,, are now, for rectangular coordinates 
In Jas = 9338 — TT 1 dE he 9 Mats 1 ik ds a : (15) 
and for polar coordinates 
eT cos ty) dig A ige (ED 
Those not mentioned are zero. 
These gq, are simpler than those of Einstein and Droste, since 
here all gj =O for /—-j. Thus e.g. the velocity of light in my 
system of reference is 
do N 
cdt Pe 
1) Droste’s formulae, like (14), only represent the field outside the sun. 
24* 
