1. The Institute of Theoretical Physics (Institut for Teoretisk Fysik) of Copenhagen University, was founded by Niels Bohr in 1921. Abraham Pais, Niels Bohr's Times in Physics, Philosophy, and Polity (Oxford: Clarendon Press, 1991), 166ff. It was often referred to as Niels Bohr's Institute. This nomenclature was used in many of the German documents relevant to the occupation. For practical reasons, the acronym NBI will be used in the present paper. In spite of the original name, NBI built up laboratory facilities for experimental research. At the time of the occupation, the equipment included advanced apparatus for experimental basic and applied atomic and nuclear research. Funds for a small cyclotron and a high-tension accelerator of the Cockroft-Walton type had been allocated by 1935. They became operational in in 1938 and 1939 respectively. A van de Graaf-accelerator, begun in 1939 and an isotope separator were under construction at the time of the occupation (Niels Ove Lassen, "Lidt af historien om cyklotronen på Niels Bohrs Institut," Fysisk Tidskrift 60 (1962), 90-119
2. Torkild Bjerge, Karl Jakob Kjærböling Brostrøm, Jørgen Koch, and T. Lauritsen, "A High Tension Apparatus for Nuclear Research," Det Kgl. Danske Videnskabernes Selskab. Mathematisk-fysiske Meddelelser 18, no. 1 (1940), 1-36. For biophysical applications see Hilde Levi, "Isotoper og biologi på Niels Bohrs Institut," Fysisk Tidsrift 60 (1962), 76-84. The university's Institute for Mathematics had been built with funds provided by the Carlsberg Foundation in direct connection to NBI and was inaugurated in 1934. Auditoria and lecture rooms were used jointly by the two institutes, and the basement was used for laboratories. Kurt Ramskov, Matematikeren Harald Bohr (Århus, Denmark: Århus Universitet, 1995), 279, 285, 351. The occupation therefore also included the Mathematics Institute, a fact often left out in contemporary documents, although the relevant subfile of the Copenhagen University: Konsistorium records in the National Archives has the title "The Requisition of the Institute for Theoretical Physics and the blocking of the Mathematics Institute by the German Armed Forces" [Den tyske Værnemagts Beslaglæggelse af Institutet for Teoretisk Fysik og Afspærring af Matematisk Institut].
3. Carl Friedrich von Weizsäcker (1912–2007) was a German physicist and philosopher. He had met Heisenberg when still at school in Copenhagen and later became his friend and protégé. After studies in Leipzig he worked in Berlin with Lise Meitner and Peter Debye. He joined the German nuclear energy and weapons program from its inception in September 1943. In 1942 he became professor of physics at the new Reichsuniversität in Strasbourg, a characteristically NS-oriented institution.
4. Jacob C. Jacobsen and Christian Møller, Rapport over Begivenhederne under Besættelsen af Universitetets Institut for teoretisk Fysik fra den 6th December 1943 til den 3 Februar 1944 [typescript, 6p.], RA/KU Kons.J.385/43, Danish National Archives, Copenhagen, Denmark (hereafter DNA). This document is undated and unsigned, but the copy in the National Archives has a handwritten comment: “Indkom 29/6 1944” (received June 29, 1944). It was probably written by Jacobsen and Møller for the university rector, who had been responsible, though mostly in the background, for the negotiations with the German authorities after the expropriation of the NBI. It contains Heisenberg’s revised strategies and his “Report,” probably the report of the expert commission. The document originally included, as appendices, an account of ongoing research at NBI, compiled to facilitate clearance from the occupation authorities. Jacob C. Jacobsen and Christian Møller, Übersicht über die wissenschaftlichen Arbeiten, die im letzten Jahr am Institut für Theoretische Physik ausgeführt worden sind [typescript], RA/KU Kons.J.185/43, DNA. There is a shorter version: “Oversigt over det Arbejde, der er udført på Institutet for Teoretisk Fysik i Løbet af det sidste års tid” [typescript], RA/KU Kons.J.385/43, DNA, and Holger W. Olsen, “Report on Interrogation,” 1944, Besøg den 11/12 1943 kl. 12.15 i Vestre Fængsel Celle Nr. 170 af 2 tyske Civilpersoner [typescript], RA/KU Kons.J.385/43, DNA. Olsen’s report is quoted in extenso in Jens Nørregaard, Københavns Universitet i Besættelsesaarene (Copenhagen: Copenhagen University, 1947), 54–55.
5. Among Germans placed in Denmark, notably: Werner Best (Reichsbevollmächtigt from 5 Nov. 1942, SS general); Günter Pancke (SS general, Höherer SS-und- Polizeiführer from 2 Nov. 1943; Rudolf Mildner (SS-Standartenführer, Head of Security Police, September 19, 1943–January 4, 1944); Otto Bovensiepen (SS-Standartenführer, Head of Security Police from January 14, 1944); Hans Wäsche (Studienrat, section leader in SD). In Danish postwar courts, Best and Bovensiepen received death sentences (converted to prison), Pancke and Wäsche twenty years in prison, but all were released after few years, on request from BRD. None was ever sentenced for their role in mass deportation and mass murder. Mildner appeared as witness in the Nuremberg tribunal and managed to escape to South America. Ulrich Herbert, Best—Biographische Studien über Radikalismus, Weltanschauung und Vernunft (Bonn: Dietz, 1996); Hans Kirchhoff, John T. Lauridsen, and Aage Trommer, eds., Hvem var hvem 1940–1945 [Gads Lexikon] (Copenhagen: Gads Forlag, 2005), 248, n7, n9; Henrik Lundtofte, Gestapo! Tysk politi og terror i Danmark 1940–45 (Copenhagen: Gad, 2003), 218, n7, n9; Højesteretstidende 14 (1950), 1–64.