THE EINSTEIN-BESSO MANUSCRIPT ON THE
MOTION OF THE PERIHELION OF MERCURY
The manuscript, written jointly by Einstein and his lifelong friend Michele Besso,
deals with the perihelion motion of Mercury on the basis of the "Entwurf" theory.
Internal and external evidence suggest that the two men closely collaborated on this
problem during a visit by Besso with Einstein in Zurich in June 1913. The bulk of the
manuscript was presumably written during this visit. Einstein may have added some
material later in 1913; some of the Besso material is certainly from later, most likely
from early 1914.
From early on in his search for a new relativistic theory of gravitation, Einstein was
interested in the problem of Mercury's perihelion. In a letter to a friend in 1907, Ein-
stein had already expressed his hope that such a theory would explain the anomalous
advance of Mercury's perihelion. After this letter, however, the Mercury anomaly is
not mentioned again, neither in Einstein's published papers nor in surviving correspon-
dence, until late 1915. On 18 November 1915 Einstein presented a paper to the
Prussian Academy of Sciences showing that his new, still developing general theory
of relativity yields a perihelion advance for Mercury of 43" per century, in striking
agreement with observation. The success carried over unproblematically to the final
version of the theory published shortly thereafter.
When Einstein subsequently reported on his new theory to Sommerfeld and
Lorentz, he mentioned that one of the reasons for abandoning the 1913 "Entwurf"
theory was that it failed to explain the Mercury anomaly. In the letter to Sommer-
feld, he explicitly mentioned that the "Entwurf" theory predicts a perihelion advance
for Mercury of 18" per century. This is also the number given by Droste in a paper
published in December 1914. The manuscript under discussion reveals that Einstein
actually did the calculation himself, shortly after he and Grossmann had finished the
"Entwurf" paper in early 1913. The expression Einstein and Besso arrived at for
For a discussion of the history of the problem of the anomalous advance of the perihelion
of Mercury, see Roseveare 1982.
See the editorial note, "Einstein on Gravitation and Relativity: The Collaboration with
Marcel Grossmann," pp. xx, for more on this theory.
Einstein to Conrad Habicht, 24 December 1907 (Vol. 5, Doc. 69).
There is a reference to calculations on perihelion motion in a letter to Erwin Freundlich,
dated 30 September 1915.
Einstein to Arnold Sommerfeld, 28 November 1915.
Einstein to H.A. Lorentz, 1 January 1916.
See Norton 1984, sec. 7.
Droste 1914, p. 1010.
Einstein and Grossmann 1913 (Doc. 13).