Gerardus J. Sizoo Gerardus J. Sizoo Gerardus Johannes Sizoo (8 November 1900 – 4 January 1994) was the first professor of physics at the Vrije Universiteit. He is notable for the establishment and development of the applied physics laboratory in 1930 and the establishment of the Faculty of Mathematics and Physics at the Vrije Universiteit. His doctoral research explored the phenomenon of superconductivity at the University of Leiden, following the lead of Heike Kamerlingh Onnes and Wander Johannes de Haas. He completed his PhD in 1926, with a thesis entitled: "Onderzoekingen over den suprageleidenden toestand van metalen," under Wander Johannes de Haas. In
Multiple scattering theory Peter Ewald. Korringa and Ewald acknowledged the influence on their work of the 1903 doctoral dissertation of Nikolai Kasterin, portions of which were published in German in the Proceedings of the Royal Academy of Sciences in Amsterdam under the sponsorship of Heike Kamerlingh Onnes. The MST formalism is widely used for electronic structure calculations as well as diffraction theory, and is the subject of many books. It should be noted that the multiple-scattering approach is the best way to derive one-electron Green's functions. These functions differ from the Green's functions used to treat the many-body problem, but they are the