Hans Geiger
Johannes (Hans) Wilhelm Geiger (September 30, 1882 - September 24, 1945) was a German physicist.
Together with Walter Müller[?] he developed the Geiger counter.
In 1902 Geiger began to study physics and mathematics in Erlangen and later attained a doctorate to 1906.
In 1907 he began work with Ernest Rutherford in Manchester.
Later in Berlin he developed, together with the graduate student Walter Müller, the Geiger counter.