During the period 1912 to 1914, Fues studied at the
University of Berlin and then the
University of Munich. He served in the military in 1914 to circa 1915, and then attended the
University of Tübingen from 1916 to 1918. During 1918, he became a student of
Arnold Sommerfeld and he received the
doctor rerum naturalium from the University of Munich in 1920. From 1922 he did postgraduate work at the Stuttgart
Technische Hochschule, under
Paul Peter Ewald, also a former student of Arnold Sommerfeld, and he completed his
Habilitation in 1924. At Stuttgart he served as a
Privatdozent and assistant to Ewald until 1929, during which time he worked on atomic and molecular structure and spectroscopy based on the
Sommerfeld-Bohr theory. During his tenure under Ewald, he was absent from 1925 to 1927, when as an International Education Board fellow, he was first an assistant to
Erwin Schrödinger at the
University of Zurich, and then a research assistant at the
University of Copenhagen at
Niels Bohr's Institute of Theoretical Physics. At that time three major centers for the development of quantum mechanics were the Theoretical Physics Institute at the University of Munich, under Arnold Sommerfeld, the Institute of Theoretical Physics at the
University of Göttingen, under
Max Born, and the Institute of Theoretical Physics, under Niels Bohr. In 1933 Fues signed the
Vow of allegiance of the Professors of the German Universities and High-Schools to Adolf Hitler and the National Socialistic State. From 1929 to 1934, he served as ordinarius professor at the
Hanover Technische Hochschule. From 1934 to 1943, he served as ordinarius professor jointly at the
University of Breslau and the
Breslau Technische Hochschule, after which, he went to the Vienna
Technische Universität, where he remained until 1947. In that year, he went back to the Stuttgart
Technische Hochschule, where the Institute for Theoretical and Applied Physics (
Institut für Theoretische und Angewandte Physik), had been formed with two chairs. Fues became ordinarius professor for theoretical physics as well as director of the institute; the other joint director was Ulrich Dehlinger. The institute followed the tradition of both Sommerfeld and Ewald in carrying on with both theoretical and experimental research and teaching. After Sommerfeld's death in 1951, Fues edited and supplemented multiple editions of two volumes of Sommerfeld's six-volume
Vorlesungen über theoretische Physik. In his career, Fues made contributions to
theoretical physics, especially in atomic structure, quantum wave mechanics, and solid-state physics. In 1960, Hermann Haken took over from Fues at the Institute for Theoretical and Applied Physics. ==Selected literature==