Philip Lenard (1862–1947) and Johannes Stark (1874–1957) were outstanding German physicists whose groundbreaking research significantly contributed to creating the foundations of modern physics necessary for the development of the field of radiology. Lenard received the Nobel Prize in 1905 for his research on cathode rays and their properties. Stark received the Nobel Prize in 1919 for his discovery of the Doppler Effect in canal rays and the splitting of spectral lines in electric fields (known as the Stark effect). Till his death, Lenard considered himself the Mother of X-rays as he had “laid all the ground work” for the discovery made by William Röntgen in 1895.
Lenard and Stark were fervent Germans nationalists and early proponents of the Nazi ideology, unequivocally supporting Adolf Hitler as early as 1924. They became the most notable leaders of the Deutsche Physik movement which reached its peak under the Nazi regime, with Lenard serving as Chief of Aryan physics. Together they led a campaign to “cleanse” German physics departments from “foreign” (euphemism for Jewish) influences in an effort to Aryanize the field of physics. They believed that the priority of scientists should be to serve the people (Volk), focusing on practical fields of research that could help German arms production and industry. They proposed that all scientific leadership positions in Germany should be held by pure-blooded Aryans. Therefore, major targets of their attack were the field of theoretical physics in general, and Albert Einstein in particular. In 1920 Lenard led an anti-Einstein campaign, against Einstein’s theories (Einsteinismus) of relativity and then against Einstein himself. The campaign escalated to death threats, mobs of brown-shirts around Einstein’s home and violent disruptions of his lectures.
Lenard and Stark’s campaign was effective in depleting German university departments of their outstanding theoretical physicists, who fled Nazi Germany. In an ironic twist, the work of these persecuted theoretical physicists was instrumental in the development of the atomic bomb by the Allied Forces. As radiologists, we have a special duty to learn about the dangers to our basic science of physics when it is compromised by political ideology.
