Christian Forstner is a Heisenberg-Fellow at the Friedrich Schiller University in Jena, Germany. Graduated in physics, he started a career in the history of science. His research focuses on the history of quantum mechanics and nuclear physics, science and society, and the material culture of physics. He was vice-president of the international Commission for the History of Modern Physics and serves as chairman of the Division for the History of Physics of the German Physical Society. Mark Walker is the John Bigelow Professor of History at Union College in Schenectady, NY, USA, where he teaches modern European history and the history of science and technology. His research focuses on the history of science, medicine, technology, and National Socialism from the First World War to the postwar Cold War era, including comparative perspectives.