Theophil Friedrich Christen

Theophil Friedrich Christen (1 April 1873 in Basel to 6 May 1920 at Lake Geneva) was a Swiss doctor, mathematician, physicist and economist, and a pioneer of physical medicine, in particular of X-ray radiation. The journal Zeitschrift für medizinische Physik wrote that he was one of the first important pioneers in medical physics, that he structured the previously confused field of physical concepts and definitions for medical applications of X-rays and that he paved the way for the modern understanding of dosimetry. He was also a vegetarian and an Esperantist, and an adherent of the reform movement, in which role he voiced racist and eugenic views that the source article records. He followed Silvio Gesell and in 1915 founded the Swiss Freigeld-Freiland Union. The Swiss Society for Radiation Biology and Medical Physics established the Theophil-Christen Medal in his honor in 2006.