It took Albert Einstein seven years to develop his equations for the theory of general relativity, and author Matthew Stanley, professor of the history of science at NYU’s Gallatin School of Individual Study, details his struggle with compassion and accuracy in his new book Einstein’s War: How Relativity Triumphed Amid the Vicious Nationalism of World War I. That Einstein was able to come as far as he did in such a comparatively small time (seven years isn’t a great deal of time in theoretical physics) is a tribute to his belief in himself and his self-discipline.
General relativity has yielded a number of interesting findings, such as:
Time dilation: Clocks run slower in deeper gravitational wells.
Light deflection: Rays of light bend in the presence of gravitational fields.
Precession: Planetary orbits rotate in a way not anticipated by Newton’s theory of gravity.
To discuss these findings in any detail would require a treatment of metric tensors and topology, at a minimum, both of which are outside the scope of this review. But these findings are truly revelatory.
The year 1914 was one of upheaval for Einstein. His marriage to Mileva had started to falter and would eventually end in divorce. And on June 28, Archduke Ferdinand of Austria was killed, along with his wife, while visiting Sarajevo. Although Einstein didn’t take much notice at the time, the archduke’s murder would be the catalyst that propelled Europe to war. Einstein’s attention was focused on activities in Russia, especially in Crimea where telescopes and cameras were being set up to track a solar eclipse. Such an effort, he hoped, would offer proof of general relativity’s prediction that light waves passing by the sun would have their paths diverted by the sun’s gravitational pull.
But with the declaration of war, Russian authorities decided that “enemy citizens with sophisticated equipment were more likely to be spies than scientists.” The leader of the eclipse expedition was arrested and imprisoned, the equipment seized. Confirming proof that gravity bends light would have to wait. And it would come, in no small measure, from an unlikely source.
Arthur Eddington was co-editor of the Royal Astronomical Society’s journal The Observatory in 1913 when he initiated a new feature — “Some Problems in Astronomy.” Such problems included spiral nebulae, counterclockwise orbiting moons, and the precise shape of the Earth.
In the February 1915 issue, he discussed the nature of gravity and was disappointed that it was still a largely unknown phenomenon. In 1911, an obscure German professor named Einstein predicted in a paper that light would change its speed in a gravitational field. But since then, Eddington had had no contact with Einstein and knew little about him.
It was difficult to be an internationalist during the war. Governments squelched communications between and among European scientists. Previous collaborators became adversaries; recognition of achievements was ignored or contested. Einstein had support from Max Planck and Ernst Mach (both Germans), as well as Hendrik Lorentz (from neutral Holland). But it was the advocacy of Arthur Eddington that was chiefly responsible for Einstein’s theory eventually gaining acceptance in the international science community.
The Armistice was finally signed Nov. 11, 1918. Plans were made to view the upcoming solar eclipse in May 1919. Preparations were thorough and viewing points would be in Principe, off the west coast of Africa, and Sobral, Brazil. Both locations would have about five minutes of viewing time and were on the eclipse’s pathway. On May 29, 1919, the eclipse came. Shutters clicked and over 20 plates recorded the results. Once back home in England, Eddington would analyze the results and prove that Einstein was right: the sun did bend light. After more than seven years of work, a world war intervening, and worldwide scientific doubt and ridicule, Einstein was triumphant.
It was a long slog for Einstein, and Stanley is there every step of the way. How could this book have been better? The illustrations in the first part of the book that try to explain time dilation, space time curvature, and Einstein’s rotating disk thought experiment could have been a little clearer; and on page 103, he makes a startling statement concerning the British Army’s casualties, that some 7,000 soldiers were killed each day. Each day? Total British killed came to just over 900,000 according to Encyclopedia Britannica. At 7,000 deaths a day, that 900,000 figure would have been reached in just over four months, when the war went on for years. Perhaps Stanley’s fingers slipped on his calculator.
These are bagatelles. Stanley has made the life of a fascinating man even more so and has contributed valuable work on the history of science.
Christopher Timmers, a West Point graduate who served in both the 82nd Airborne and Third Infantry divisions in Germany, lives in South Carolina.
