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).
Aurel Stodola Aurel Boleslav Stodola (10 May 1859 – 25 December 1942) was a Slovak engineer, physicist, and inventor. He was a pioneer in the area of technical thermodynamics and its applications and published his book "Die Dampfturbine" (the steam turbine) in 1903. In addition to the thermodynamic issues involved in turbine design the book discussed aspects of fluid flow, vibration, stress analysis of plates, shells and rotating discs and stress concentrations at holes and fillets. Stodola was a professor of mechanical engineering at the Swiss Polytechnical Institute (now ETH) in Zurich. One of his students was Albert Einstein. In 1892, Stodola founded the Laboratory for Energy Conversion.