Abraham Esau
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Robert Abraham Esau (7 June 1884 – 12 May 1955) was a German
physicist A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate cau ...
. After receipt of his doctorate from the
University of Berlin The Humboldt University of Berlin (, abbreviated HU Berlin) is a public research university in the central borough of Mitte in Berlin, Germany. The university was established by Frederick William III on the initiative of Wilhelm von Humbol ...
, Esau worked at
Telefunken Telefunken was a German radio and television producer, founded in Berlin in 1903 as a joint venture between Siemens & Halske and the ''AEG (German company), Allgemeine Elektrizitäts-Gesellschaft'' (AEG) ("General electricity company"). Prior to ...
, where he pioneered very high frequency (VHF) waves used in radar, radio, and television, and he was president of the ''Deutscher Telefunken Verband''. During World War I, he was a prisoner of war of the French; he was repatriated to Germany in 1919. In 1925, he was appointed professor at the University of Jena, where he also served as rector. From 1933, Esau was the State Councilor in
Thuringia Thuringia (; officially the Free State of Thuringia, ) is one of Germany, Germany's 16 States of Germany, states. With 2.1 million people, it is 12th-largest by population, and with 16,171 square kilometers, it is 11th-largest in area. Er ...
. From 1937, Esau was head of the physics section of the newly created Reich Research Council (RFR). From 1939, he was a professor at the
University of Berlin The Humboldt University of Berlin (, abbreviated HU Berlin) is a public research university in the central borough of Mitte in Berlin, Germany. The university was established by Frederick William III on the initiative of Wilhelm von Humbol ...
and president of the Reich Physical and Technical Institute. From his position in the RFR, he initiated the first meeting of the Uranium Club in early 1939, the precursor to the Army Ordnance Office (HWA) German nuclear energy project, which began in September of that year. When the HWA gave control of the project to the RFR in 1942, Esau became the plenipotentiary of nuclear physics and was in control of the project. In 1944, Esau became the plenipotentiary of the high-frequency engineering and radar working group. During World War II, Esau was one of the most powerful physicists in Germany. After World War II until 1948, Esau was a prisoner of war of the Dutch. From 1949, Esau was a visiting professor of short-wave technology at the
RWTH Aachen RWTH Aachen University (), in German ''Rheinisch-Westfälische Technische Hochschule Aachen'', is a German public research university located in Aachen, North Rhine-Westphalia, Germany. With more than 47,000 students enrolled in 144 study prog ...
. From 1953, he was also head of the Institute of High-Frequency Engineering of the German Aeronautical Research Institute.


Education

Esau was born in Tiegenhagen ( Tujec) in Landkreis Marienburg, West Prussia. He was the son of Prussian
Mennonites Mennonites are a group of Anabaptism, Anabaptist Christianity, Christian communities tracing their roots to the epoch of the Radical Reformation. The name ''Mennonites'' is derived from the cleric Menno Simons (1496–1561) of Friesland, part of ...
, Osar Abraham Esau (1861–1945) and Maria Agnes (Regier) Esau (1861–1892). From 1902 to 1907, Esau studied at the ''Friedrich-Wilhelms-Universität'' (today, the
Humboldt University of Berlin The Humboldt University of Berlin (, abbreviated HU Berlin) is a public research university in the central borough of Mitte in Berlin, Germany. The university was established by Frederick William III on the initiative of Wilhelm von Humbol ...
) and the ''Königliche Technische Hochschule zu Danzig'' (today, Gdańsk University of Technology). From 1906 to 1909, he was a teaching assistant to Max Wien at Danzig. He received his doctorate at the University of Berlin in 1908.Hentschel and Hentschel, 1996, Appendix F; see the entry for Esau.


Career


Early years

From 1909 to 1910, Esau was a volunteer at the radio transmission division of the Berlin telegraph battalion. From 1910 to 1912, he was teaching assistant at the '' Martin-Luther-Universität Halle-Wittenberg''. From 1914, he was on active duty with the German military in
Togo Togo, officially the Togolese Republic, is a country in West Africa. It is bordered by Ghana to Ghana–Togo border, the west, Benin to Benin–Togo border, the east and Burkina Faso to Burkina Faso–Togo border, the north. It is one of the le ...
; he became a prisoner of war of the French and did not return to Germany until 1918. From 1912 to 1925, Esau served as laboratory chairman of the ''Gesellschaft für drahtlose Telegraphie'' (Wireless Telegraph Society) in Berlin. During this time, at ''
Telefunken Telefunken was a German radio and television producer, founded in Berlin in 1903 as a joint venture between Siemens & Halske and the ''AEG (German company), Allgemeine Elektrizitäts-Gesellschaft'' (AEG) ("General electricity company"). Prior to ...
'', he pioneered very high frequency ( VHF) waves used in radar, radio, and television. In 1921 and 1922, he had stays in Argentina and Brazil. From 1925, Esau was president of the ''Deutscher Telefunken Verband''. In 1925, Esau began his association with the Friedrich Schiller University of Jena. From 1925 to 1927, he was an extraordinarius professor of technical physics, and from 1927 to 1939, he was an ordinarius professor of technical physics and director of the department of technical physics. He was rector there from 1932 to 1935 and in 1937. Dr. Esau was also the advisor of Dr. Lothar Rohde and Dr. Hermann Schwarz, who later founded the company Rohde & Schwarz, in 1933 during their doctorate in Friedrich Schiller University of Jena. In October 1933, Esau became a '' Staatsrat'' (State Councilor) in
Thuringia Thuringia (; officially the Free State of Thuringia, ) is one of Germany, Germany's 16 States of Germany, states. With 2.1 million people, it is 12th-largest by population, and with 16,171 square kilometers, it is 11th-largest in area. Er ...
, a position he held until the end of World War II. This role gave him direct access to
Adolf Hitler Adolf Hitler (20 April 1889 – 30 April 1945) was an Austrian-born German politician who was the dictator of Nazi Germany from 1933 until Death of Adolf Hitler, his suicide in 1945. Adolf Hitler's rise to power, He rose to power as the lea ...
. Kurt Diebner ''Listing of Nuclear Research Commissions Enclosed with a Letter to the President of the Reich Research Council 8 April. 1944' in Document No. 104 in Hentschel and Hentschel, 1996, 322–324. On the initiative of Erich Schumann, the ''
Reichsforschungsrat The Reichsforschungsrat ("Imperial Research Council") was created in Germany in 1936 under the Education Ministry for the purpose of centralized planning of all basic and applied research, with the exception of aeronautical research. It was reorgani ...
'' (RFR, Reich Research Council) was inaugurated on 16 March 1937 by Reich Minister Bernhard Rust of the '' Reichserziehungsministerium'' (REM, Reich Education Ministry). The RFR was set up to centralize planning for all basic and applied research in Germany, with the exception of aeronautical research, which was under the supervision of Reich Marshal
Hermann Göring Hermann Wilhelm Göring (or Goering; ; 12 January 1893 – 15 October 1946) was a German Nazism, Nazi politician, aviator, military leader, and convicted war criminal. He was one of the most powerful figures in the Nazi Party, which gov ...
. Support for research was decided by the heads of 13 special sections of the RFR (Fachspatenleiter). Esau was a member of the RFR from its inception, and he was head of the physics section (Fachspatenleiter für Physik), which included mathematics, astronomy, and meteorology. From this position in the RFR, he would play major roles in the German nuclear energy project, sometimes also referred to as the ''Uranverein'' (Uranium Club).Hoffmann, 2005, 305–306. In 1938, Esau was appointed Professor of Military Telecommunications Technology in the Faculty of Military Engineering, which had recently been founded at the Technische Hochschule Berlin (today, the ''
Technische Universität Berlin (TU Berlin; also known as Berlin Institute of Technology and Technical University of Berlin, although officially the name should not be translated) is a public university, public research university located in Berlin, Germany. It was the first ...
''), in Berlin-Charlottenburg. From 1939 to 1945, Esau was ordinarius professor at the University of Berlin and president of the ''Physikalisch-Technische Reichsanstalt'' (PTR, Reich Physical and Technical Institute; today, the
Physikalisch-Technische Bundesanstalt The Physikalisch-Technische Bundesanstalt (PTB) is the national metrology institute of the Federal Republic of Germany, with scientific and technical service tasks. It is a higher federal authority and a public-law institution directly under fed ...
). At the same time he was a visiting lecturer at the ''Technische Akademie Bergisch-Land'' (Technical Academy of
Bergisches Land The Bergisches Land (, ) is a low mountain range in the state of North Rhine-Westphalia, Germany, east of the Rhine and south of the Ruhr. The landscape is shaped by forests, meadows, rivers and creeks and contains over twenty artificial lakes ...
). Additionally, for this same period, Esau was president of the ''Deutsche Gemeinschaft zur Erhaltung und Förderrung der Forschung'' (German Association for the Support and Advancement of Scientific Research), also known for short as the '' Deutsche Forschungs-Gemeinschaft'' (DFG), which had before 1937 been known as the '' Notgemeinschaft der Deutschen Wissenschaft'' (NG; Emergency Association of German Science).


World War II and the ''Uranverein''

Shortly after the discovery of
nuclear fission Nuclear fission is a reaction in which the nucleus of an atom splits into two or more smaller nuclei. The fission process often produces gamma photons, and releases a very large amount of energy even by the energetic standards of radioactiv ...
in December 1938/January 1939, the '' Uranverein'', i.e., the German nuclear energy project, had an initial start in April before being formed a second time under the '' Heereswaffenamt'' (HWA, Army Ordnance Office) in September.


First ''Uranverein''

Paul Harteck was director of the physical chemistry department at the
University of Hamburg The University of Hamburg (, also referred to as UHH) is a public university, public research university in Hamburg, Germany. It was founded on 28 March 1919 by combining the previous General Lecture System ('':de:Allgemeines Vorlesungswesen, ...
and an advisor to the ''Heereswaffenamt'' (HWA, Army Ordnance Office). On 24 April 1939, along with his teaching assistant Wilhelm Groth, Harteck made contact with the ''Reichskriegsministerium'' (RKM, Reich Ministry of War) to alert them to the potential of military applications of nuclear chain reactions. Two days earlier, on 22 April 1939, after hearing a colloquium paper by Wilhelm Hanle on the use of
uranium Uranium is a chemical element; it has chemical symbol, symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Ura ...
fission in a ''Uranmaschine'' (uranium machine, i.e.,
nuclear reactor A nuclear reactor is a device used to initiate and control a Nuclear fission, fission nuclear chain reaction. They are used for Nuclear power, commercial electricity, nuclear marine propulsion, marine propulsion, Weapons-grade plutonium, weapons ...
), Georg Joos, along with Hanle, notified Wilhelm Dames, at the '' Reichserziehungsministerium'' (REM, Reich Ministry of Education), of potential military applications of nuclear energy. The communication was given to Abraham Esau, head of the physics section of the ''
Reichsforschungsrat The Reichsforschungsrat ("Imperial Research Council") was created in Germany in 1936 under the Education Ministry for the purpose of centralized planning of all basic and applied research, with the exception of aeronautical research. It was reorgani ...
'' (RFR, Reich Research Council) at the REM. On 29 April, a group, organized by Esau, met at the REM to discuss the potential of a sustained nuclear chain reaction. The group included the physicists Walther Bothe, Robert Döpel,
Hans Geiger Johannes Wilhelm Geiger ( , ; ; 30 September 1882 – 24 September 1945) was a German nuclear physicist. He is known as the inventor of the Geiger counter, a device used to detect ionizing radiation, and for carrying out the Rutherford scatt ...
, Wolfgang Gentner (probably sent by Walther Bothe), Wilhelm Hanle, Gerhard Hoffmann, and Georg Joos; Peter Debye was invited, but he did not attend. After this, informal work began at the Georg-August University of Göttingen by Joos, Hanle, and their colleague Reinhold Mannfopff; the group of physicists was known informally as the first ''Uranverein'' (Uranium Club) and formally as ''Arbeitsgemeinschaft für Kernphysik''. The group's work was discontinued in August 1939, when the three were called to military training.Macrakis, 1993, 164–169. Jagdish Mehra and Helmut Rechenberg ''The Historical Development of Quantum Theory. Volume 6. The Completion of Quantum Mechanics 1926–1941. Part 2. The Conceptual Completion and Extension of Quantum Mechanics 1932–1941. Epilogue: Aspects of the Further Development of Quantum Theory 1942–1999.'' (Springer, 2001), pp. 1011–1011.


Second ''Uranverein''

The second ''Uranverein'' began after the ''Heereswaffenamt'' squeezed out the ''
Reichsforschungsrat The Reichsforschungsrat ("Imperial Research Council") was created in Germany in 1936 under the Education Ministry for the purpose of centralized planning of all basic and applied research, with the exception of aeronautical research. It was reorgani ...
'' of the '' Reichserziehungsministerium'' and started the formal German nuclear energy project under military auspices. The second ''Uranverein'' was formed on 1 September 1939, the day World War II began, and it had its first meeting on 16 September 1939. The meeting was organized by Kurt Diebner, advisor to the HWA, and held in Berlin. The invitees included Walther Bothe, Siegfried Flügge,
Hans Geiger Johannes Wilhelm Geiger ( , ; ; 30 September 1882 – 24 September 1945) was a German nuclear physicist. He is known as the inventor of the Geiger counter, a device used to detect ionizing radiation, and for carrying out the Rutherford scatt ...
,
Otto Hahn Otto Hahn (; 8 March 1879 – 28 July 1968) was a German chemist who was a pioneer in the field of radiochemistry. He is referred to as the father of nuclear chemistry and discoverer of nuclear fission, the science behind nuclear reactors and ...
, Paul Harteck, Gerhard Hoffmann, Josef Mattauch, and Georg Stetter. A second meeting was held soon thereafter and included Klaus Clusius, Robert Döpel,
Werner Heisenberg Werner Karl Heisenberg (; ; 5 December 1901 – 1 February 1976) was a German theoretical physicist, one of the main pioneers of the theory of quantum mechanics and a principal scientist in the German nuclear program during World War II. He pub ...
, and Carl Friedrich von Weizsäcker. Also at this time, the ''Kaiser-Wilhelm Institut für Physik'' (KWIP, Kaiser Wilhelm Institute for Physics, after World War II the Max Planck Institute for Physics), in Berlin-Dahlem, was placed under HWA authority, with Diebner as the administrative director, and the military control of the nuclear research commenced. When it was apparent that the nuclear energy project would not make a decisive contribution to ending the war effort in the near term, control of the KWIP was returned in January 1942 to its umbrella organization, the '' Kaiser-Wilhelm Gesellschaft'' (KWG, Kaiser Wilhelm Society, after World War II the Max-Planck Gesellschaft), and HWA control of the project was relinquished to the RFR in July 1942. The nuclear energy project thereafter maintained its ''kriegswichtig'' (important for the war) designation and funding continued from the military. On 9 June 1942,
Adolf Hitler Adolf Hitler (20 April 1889 – 30 April 1945) was an Austrian-born German politician who was the dictator of Nazi Germany from 1933 until Death of Adolf Hitler, his suicide in 1945. Adolf Hitler's rise to power, He rose to power as the lea ...
issued a decree for the reorganization of the RFR as a separate legal entity under the '' Reichsministerium für Bewaffnung und Munition'' (RMBM, Reich Ministry for Armament and Ammunition, after autumn 1943 the Reich Ministry for Armament and War Production); the decree appointed Reich Marshal
Hermann Göring Hermann Wilhelm Göring (or Goering; ; 12 January 1893 – 15 October 1946) was a German Nazism, Nazi politician, aviator, military leader, and convicted war criminal. He was one of the most powerful figures in the Nazi Party, which gov ...
as the president. The reorganization was done under the initiative of Reich Minister for Armament and Ammunition
Albert Speer Berthold Konrad Hermann Albert Speer (; ; 19 March 1905 – 1 September 1981) was a German architect who served as Reich Ministry of Armaments and War Production, Minister of Armaments and War Production in Nazi Germany during most of W ...
; it was necessary as the RFR under Minister Bernhard Rust was ineffective and not achieving it purpose. It was the hope that Göring would manage the RFR with the same discipline and efficiency as he had in the aviation sector. On 8 December 1942, Abraham Esau was appointed as Hermann Göring's ''Bevollmächtiger'' (plenipotentiary) for nuclear physics research under the RFR – at this point, Esau was in charge of the German nuclear energy project. At the end of 1943, Esau resigned as plenipotentiary of nuclear physics; in December, Walther Gerlach replaced him as plenipotentiary for nuclear physics and as head of the physics section of the RFR. As of 1 January 1944, Esau, replacing Johannes Plendl, became the plenipotentiary of the high-frequency engineering and radar working group (''A. G. Hochfrequenzphysik''). In the final analysis, placing the RFR under Göring's administrative control had little effect on the German nuclear energy project. Over time, the HWA and then the RFR controlled the German nuclear energy project. The most influential people were Erich Schumann, Abraham Esau, Walther Gerlach, and Kurt Diebner. During World War II, Esau was one of the most powerful and influential physicists in Germany. Even after Esau left his position as plenipotentiary for nuclear physics and head of the physics section at the RFR at the end of 1942, he continued to have significant authority and influence as president of the ''Physikalisch-Technische Reichsanstalt'', as is attested to by the fact that he was able to continue research efforts for the ''Urainverein'' under the highest priority level for urgent development projects (''Dringlichkeitsentwicklung, DE'').


Post-World War II

After the war, the Americans turned Esau over to the Dutch to stand trial for his involvement in the plunder of research facilities of the electronics firm
Philips Koninklijke Philips N.V. (), simply branded Philips, is a Dutch multinational health technology company that was founded in Eindhoven in 1891. Since 1997, its world headquarters have been situated in Amsterdam, though the Benelux headquarter ...
. He was acquitted and expelled in 1948. Later, he was tried and convicted ''
in absentia ''In Absentia'' is the seventh studio album by British progressive rock band Porcupine Tree, first released on 24 September 2002. The album marked several changes for the band, with it being the first with new drummer Gavin Harrison and the f ...
''; without a conviction, the Dutch could not make a legal claim for damages from Germany. Thanks to support from Leo Brandt, a science policy-maker of
North Rhine-Westphalia North Rhine-Westphalia or North-Rhine/Westphalia, commonly shortened to NRW, is a States of Germany, state () in Old states of Germany, Western Germany. With more than 18 million inhabitants, it is the List of German states by population, most ...
, Esau was able to establish himself back into the German scientific community. From 1949, Esau was a visiting professor of short-wave technology at the
RWTH Aachen University RWTH Aachen University (), in German ''Rheinisch-Westfälische Technische Hochschule Aachen'', is a German public research university located in Aachen, North Rhine-Westphalia, Germany. With more than 47,000 students enrolled in 144 study prog ...
. From 1953, he was also head of the Institute of High-Frequency Engineering of the German Aeronautical Research Institute in Mülheim an der Ruhr. Esau died in
Düsseldorf Düsseldorf is the capital city of North Rhine-Westphalia, the most populous state of Germany. It is the second-largest city in the state after Cologne and the List of cities in Germany with more than 100,000 inhabitants, seventh-largest city ...
.


Honors

In 1954, he received an honorary doctorate from the '' Albert-Ludwigs-Universität Freiburg'' for his work on diathermy. In 1954 the science policy-maker of
North Rhine-Westphalia North Rhine-Westphalia or North-Rhine/Westphalia, commonly shortened to NRW, is a States of Germany, state () in Old states of Germany, Western Germany. With more than 18 million inhabitants, it is the List of German states by population, most ...
, Leo Brant, nominated Esau for a medal of distinction. The award was not made, due to the intervention of the physicist Max von Laue, who pointed out Esau's prominent role as a chief representative of National Socialism.


Internal reports

The following reports were published in '' Kernphysikalische Forschungsberichte'' (''Research Reports in Nuclear Physics''), an internal publication of the German '' Uranverein''. The reports were classified Top Secret, they had very limited distribution, and the authors were not allowed to keep copies. The reports were confiscated under the Allied Operation Alsos and sent to the
United States Atomic Energy Commission The United States Atomic Energy Commission (AEC) was an agency of the United States government established after World War II by the U.S. Congress to foster and control the peacetime development of atomic science and technology. President Harry ...
for evaluation. In 1971, the reports were declassified and returned to Germany. The reports are available at the Karlsruhe Nuclear Research Center and the
American Institute of Physics The American Institute of Physics (AIP) promotes science and the profession of physics, publishes physics journals, and produces publications for scientific and engineering societies. The AIP is made up of various member societies. Its corpora ...
.Walker, 1993, 268–274. *Abraham Esau ''Herstellung von Leuchtfarben ohne Anwendung von Radium'' G-213 (5 May 1943) *Abraham Esau ''Einleitung'' G-214 (5 May 1943)


Books

*Abraham Esau, ''Weltnachrichtenverkehr und Weltnachrichtenmonopole'' (Fischer, 1932) *Abraham Esau, ''375 Jahre Universität Jena'' (Fischer, 1933) *Abraham Esau, ''Die Entwicklung der deutschen drahtlosen Nachrichtentechnik'' (Fischer, 1934) *Abraham Esau, ''Einführung zu den Berichten der Herren Frhr von Handel und Plendl'' (Oldenbourg, 1939) *Abraham Esau, ''Elektrische Wellen im Zentimetergebiet'' (Oldenbourg, 1940) *Abraham Esau, ''Werner von Siemens'' (de Gruyter, 1943) *Abraham Esau, ''Ortung mit elektrischen und Ultraschallwellen in Technik und Natur'' (Westdeutscher Verlag, 1953) *Abraham Esau, ''Der Ultraschall und seine technischen Anwendungen'' (Westdeutscher Verlag, 1955)


Notes


References

* ''A. Esau'', ''Das Reich Deutsche Wochenzeitung'' Berlin, No. 29, 16 July 1944, p. 1. The English translation and reprint of this tribute to Abraham Esau for his 61st is Document #105, ''A raham Esau 6 July 1944' in Hentschel, Klaus (editor) and Ann M. Hentschel (editorial assistant and translator) ''Physics and National Socialism: An Anthology of Primary Sources'' (Birkhäuser, 1996) 324–327. *Beyerchen, Alan D. ''Scientists Under Hitler: Politics and the Physics Community in the Third Reich'' (Yale, 1977) * Diebner, Kurt ''Listing of Nuclear Research Commissions Enclosed with a Letter to the President of the Reich Research Council 8 April. 1944' in Document No. 104 in Hentschel, Klaus (editor) and Ann M. Hentschel (editorial assistant and translator) ''Physics and National Socialism: An Anthology of Primary Sources'' (Birkhäuser, 1996) 322–324. The document was issued by direction of Kurt Diebner as a Reich Planning Officer. *Esau, Abraham ''Technische Physic'', in ''Deutsche Wissenschaft. Arbeit und Aufgabe'' (Hirzel, 1939) pp. 171–172. The English translation and reprint of this article is Document No. 72 in Hentschel, Klaus (editor) and Ann M. Hentschel (editorial assistant and translator) ''Physics and National Socialism: An Anthology of Primary Sources'' (Birkhäuser, 1996) 193–194. *Esau, Abraham ''Memorandum on the Budget of the Plenipotentiary of Nuclear Physics Research 9 November 1943', Document No. 103 in Hentschel, Klaus (editor) and Ann M. Hentschel (editorial assistant and translator) ''Physics and National Socialism: An Anthology of Primary Sources'' (Birkhäuser, 1996) 321–322. * Hentschel, Klaus, editor and Ann M. Hentschel, editorial assistant and Translator ''Physics and National Socialism: An Anthology of Primary Sources'' (Birkhäuser, 1996) * Klaus Hentschel ''The Mental Aftermath: The Mentality of German Physicists 1945–1949'' (Oxford, 2007) *Hoffmann, Dieter ''Between Autonomy and Accommodation: The German Physical Society during the Third Reich'', ''Physics in Perspective'' 7(3) 293–329 (2005) *Kant, Horst ''Werner Heisenberg and the German Uranium Project / Otto Hahn and the Declarations of Mainau and Göttingen'', Preprint 203 (Max-Planck Institut für Wissenschaftsgeschichte
2002
*Macrakis, Kristie ''Surviving the Swastika: Scientific Research in Nazi Germany'' (Oxford, 1993) *Walker, Mark ''German National Socialism and the Quest for Nuclear Power 1939–1949'' (Cambridge, 1993)


External links

* {{DEFAULTSORT:Esau, Abraham 1884 births 1955 deaths People from Nowy Dwór Gdański County People from West Prussia Nuclear program of Nazi Germany Humboldt University of Berlin alumni Gdańsk University of Technology alumni Academic staff of the Humboldt University of Berlin Academic staff of Technische Universität Berlin Academic staff of the University of Jena Recipients of the Knights Cross of the War Merit Cross 20th-century German physicists German military personnel of World War I