"In a memoir published four years ago - Die Plancksche Theorie der Strahlung, 1907 - I tried to answer the question whether the propagation of light is influenced by gravitation. I return to this theme, because my previous presentation of the subject does not satisfy me, and for a stronger reason, because I now see that one of the most important consequences of my former treatment is capable of being tested experimentally. For it follows from the theory here to be brought forward, that rays of light, passing close to the sun, are deflected by its gravitational field, so that the angular distance between the sun and a fixed star appearing near to it is apparently increased by nearly a second of arc." -Einstein
FIRST EDITION – EINSTEIN'S SON HANS ALBERT'S COPY – OF THE EXTREMELY RARE AUTHOR'S PRESENTATION OFFPRINT OF HIS IMPORTANT PAPER ON THE DEFLECTION OF LIGHT BY GRAVITATION; HIS FIRST PAPER WHOLLY DEDICATED TO THE GENERAL THEORY OF RELATIVITY.
One consequence of Einstein’s Equivalence Principle, proposed in 1907, “is that gravity, as Einstein had noted, should bend a light beam... For almost four years after positing this principle, Einstein did little with it. Instead, he focused on light quanta. But in 1911, he confessed to Michele Besso that he was weary of worrying about quanta, and he turned his attention back to coming up with a field theory of gravity that would help him generalize relativity. It was a task that would take him almost four more years, culminating in an eruption of genius in Novemeber 1915...
“In a paper he sent to the Annalen der Physik in June 1911, ‘On the Influence of Gravity on the Propagation of Light,’ he picked up his insight from 1907 and gave it rigorous expression. ‘In a memoir published four years ago I tried to answer the question whether the propagation of light is influenced by gravitation,’ he began. ‘I now see that one of the most important consequences of my former treatment is capable of being tested experimentally.’ After a series of calculations, Einstein came up with a prediction for light passing through the gravitational field next to the sun: 'A ray of light going past the sun would undergo a deflection of 0.83 second of arc.’
“Once again, he was deducing a theory from grand principles and postulates, then deriving some predictions that experimenters could proceed to test. As before, he ended his paper by calling for just such a test. ‘As the stars in the parts of the sky near the sun are visible during total eclipses of the sun, this consequence of the theory may be observed. It would be a most desireable thing if astronomers would take up the question’” (Isaacson, 190-1). After perfecting his equations for the general theory of relativity in 1915 Einstein was forced to modify his deflection prediction; a prediction which, after Arthur Eddington’s celebrated experimental proof, made Einstein world famous.
Provenance: Hans Albert Einstein (1904-73) (ownership stamp on front wrapper). The second child and first son of Albert Einstein and Mileva Marić, Hans Albert moved to the US in 1938, and spent most of his career at the University of California, Berkeley, where he was a professor of hydraulic engineering.
OFFPRINT FROM: Annalen der Physik, Band 35, Heft 5., No. 10., pp. 898-908. Leipzig: Johann Ambrosius Barth, 1911. Octavo (222 x 144 mm), pp. [1, blank], 898–908. Original printed orange wrappers, stamped ‘A. Einstein. Überreicht vom Verfasser’ above printed title. Custom box. A fine copy.