Otto Stern is the second most nominated person for a Nobel Prize behind a German theoretical physicist who pioneered developments in what?
Arnold Sommerfeld Arnold Johannes Wilhelm Sommerfeld, {'1': ", '2': ", '3': 'ForMemRS', '4': "} (] ; 5 December 1868 – 26 April 1951) was a German theoretical physicist who pioneered developments in atomic and quantum physics, and also educated and mentored a large number of students for the new era of theoretical physics. He served as PhD supervisor for many Nobel Prize winners in physics and chemistry (only J. J. Thomson's record of mentorship is comparable to his).
Theodor W. Hänsch Theodor Wolfgang Hänsch (born 30 October 1941) is a German physicist. He received one fourth of the 2005 Nobel Prize in Physics for "contributions to the development of laser-based precision spectroscopy, including the optical frequency comb technique", sharing the prize with John L. Hall and Roy J. Glauber.