Ernst Rexer

[1][circular reference] After completing his high schooling in 1921, he enrolled in University of Freiburg to study physics and chemistry; he passed his chemist association's exam in 1926.

[2] Through his employment's sponsorship, he attended the Humboldt University of Berlin and began working on his doctoral thesis on physics of crystallization in 1929–30.

Abraham Esau was President of the PTR, and he took control of the Uranverein in December, when he was appointed Plenipotentiary (Bevollmächtiger) for Nuclear Physics.

[2][3][4] While Rexer was at the PTR, some of the research was carried out at the Versuchsstelle (testing station) of the HWA in Gottow; Kurt Diebner, was director of the facility.

The testing station is where Rexer, F. Berkei, W. Borrmann, W. Czulius, Kurt Diebner, Georg Hartwig, Karl-Heinz Höcker, Walter Herrmann, and Heinz Pose, compared the effectiveness of neutron production in a paraffin-moderated reactor using uranium plates, rods, and cubes.

The G-1 experiment performed at the HWA testing station had lattices of 6,800 uranium oxide cubes (about 25 tons) in the neutron moderator paraffin.

)[8][9] On 5 March 1946, in order to staff his laboratory, Pose and NKVD General Kravchenko, along with two other officers, went to Germany for six months to hire scientists.

Additionally, Pose procured equipment from the companies AEG, Zeiss, Schott Jena, and Mansfeld, which were in the Russian occupation zone.

Three heads of laboratories, Czulius, Herrmann, and Rexer, were Pose's colleagues who worked with him at the German Army's testing station in Gottow, under the Uranverein project.