My interview with National Public Radio’s Science Friday on the 100th anniversary of the announcement that gravity bends light just as Einstein predicted, based on my book, Gravity’s Century
My NY Times blog post on the 100th anniversary of the announcement that made Einstein a worldwide celebrity, based on my book Gravity’s Century
Friday’s Wall Street Journal featured a great review of my book:
In “Gravity’s Century” (Harvard, 181 pages, $26.95), science journalist Ron Cowen takes the long view. His brisk, engaging narrative leads us from Einstein’s famous “thought experiments” through theorists’ many (so far unsuccessful) attempts to marry quantum mechanics with general relativity, and up to recent (more successful) efforts to observe gravitational waves and black holes.
Explanations of key concepts in physics are interspersed with breezy biographical sketches of key figures in their development. Some tales—like the story of Einstein imagining what it would be like to ride alongside a light beam—are familiar. But Mr. Cowen’s book also introduces us to the prehistory of general relativity, featuring less-known characters like János Bolyai and Nikolai Lobachevsky, whose insights transformed geometry and set the stage for Einstein. A “deeper dive” accompanies each chapter, providing technical and historical asides for more earnest readers.
“Gravity’s Century,” like the other two books but more succinctly, recounts earlier eclipse expeditions aimed at testing the light-bending prediction. These included the misadventure that befell German astronomer Erwin Finlay-Freundlich and his colleagues. Encouraged by Einstein himself, they had traveled to Crimea to observe a 1914 eclipse, but when the war broke out were arrested as enemy aliens and had their telescopes confiscated. The researchers were released in a prisoner exchange, but the Russians held on to their equipment for much longer. As Mr. Cowen explains, the foiled excursion “proved lucky for Einstein. Late in 1915 he realized that the correct deflection of starlight was actually twice what he had calculated in 1911, before he had fully developed his new theory of gravity.” Finlay-Freundlich’s observations, had he been able to make them, would have seemed to contradict Einstein’s theory.
Ultimately, Einstein forged “a new way of thinking not just about gravity but about the universe,” as Mr. Cowen puts it. He refuted “long-held notions of space and time as featureless, silent spectators to the comings and goings in the universe.” A century later we continue to marvel at the awesome ramifications of Einstein’s radical notion.