In the first decade of the twentieth century, science initiated a second American revolution. A nation on horseback was soon transformed by the internal combustion engine, manned flight, and a multitude of other inventions. These technological innovations quickly changed the lives of ordinary men and women. But simultaneously an esoteric band of scientists was creating an even more fundamental revolution. Theoretical physicists across the globe were beginning to alter the way we understand space and time. Radioactivity was discovered in 1896, by the French physicist Henri Becquerel. Max Planck, Marie Curie and Pierre Curie and others provided further insights into the nature of the atom. And then, in 1905, Albert Einstein published his special theory of relativity. Suddenly, the universe appeared to have changed.
-Kai Bird and Martin J. Sherwin, American Prometheus: The Triumph and Tragedy of J. Robert Oppenheimer