Stefan Rozental (13 August 1903,

Łódź Łódź, also rendered in English as Lodz, is a city in central Poland and a former industrial centre. It is the capital of Łódź Voivodeship, and is located approximately south-west of Warsaw. The city's coat of arms is an example of cant ...

– 2 August 1994,

Copenhagen Copenhagen ( or .; da, København ) is the capital and most populous city of Denmark, with a proper population of around 815.000 in the last quarter of 2022; and some 1.370,000 in the urban area; and the wider Copenhagen metropolitan ar ...

), was a nuclear physicist, specialising in

quantum mechanics Quantum mechanics is a fundamental theory in physics that provides a description of the physical properties of nature at the scale of atoms and subatomic particles. It is the foundation of all quantum physics including quantum chemistr ...

. Trapped outside Poland when

World War I World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...

started, he and his parents ended up in Denmark and spent four years from 1915 there before they returned to their native Poland in 1919 after the war. He received his PhD from the

University of Kraków The Jagiellonian University ( Polish: ''Uniwersytet Jagielloński'', UJ) is a public research university in Kraków, Poland. Founded in 1364 by King Casimir III the Great, it is the oldest university in Poland and the 13th oldest university in ...

in 1928. He later held an assistant position with

Werner Heisenberg Werner Karl Heisenberg () (5 December 1901 – 1 February 1976) was a German theoretical physicist and one of the main pioneers of the theory of quantum mechanics. He published his work in 1925 in a breakthrough paper. In the subsequent serie ...

Leipzig Leipzig ( , ; Upper Saxon: ) is the most populous city in the German state of Saxony. Leipzig's population of 605,407 inhabitants (1.1 million in the larger urban zone) as of 2021 places the city as Germany's eighth most populous, as ...

between 1929 and 1934 and lectured in

Kraków Kraków (), or Cracow, is the second-largest and one of the oldest cities in Poland. Situated on the Vistula River in Lesser Poland Voivodeship, the city dates back to the seventh century. Kraków was the official capital of Poland until 1596 ...

between 1934 and 1938. Due to the rising

Antisemitism Antisemitism (also spelled anti-semitism or anti-Semitism) is hostility to, prejudice towards, or discrimination against Jews. A person who holds such positions is called an antisemite. Antisemitism is considered to be a form of racism. Antis ...

in Poland he emigrated to

Denmark ) , song = ( en, "King Christian stood by the lofty mast") , song_type = National and royal anthem , image_map = EU-Denmark.svg , map_caption = , subdivision_type = Sovereign state , subdivision_name = Kingdom of Denmark , establish ...

and arrived in

in March 1938 where

Niels Bohr Niels Henrik David Bohr (; 7 October 1885 – 18 November 1962) was a Danish physicist who made foundational contributions to understanding atomic structure and quantum theory, for which he received the Nobel Prize in Physics in 1922 ...

admitted him to his institute. From 1940, after

Hendrik Anthony Kramers Hendrik Anthony "Hans" Kramers (17 December 1894 – 24 April 1952) was a Dutch physicist who worked with Niels Bohr to understand how electromagnetic waves interact with matter and made important contributions to quantum mechanics and statistical ...

(from 1916) and

Léon Rosenfeld Léon Rosenfeld (; 14 August 1904 in Charleroi – 23 March 1974) was a Belgian physicist and Marxist. Rosenfeld was born into a secular Jewish family. He was a polyglot who knew eight or nine languages and was fluent in at least five of the ...

(from 1934), he was

's personal assistant for almost fifteen years, whom he assisted even into the early sixties after both returned to

in 1945.

Literature

* Stefan Rozental, ed., ''Niels Bohr: His Life and Work As Seen by His Friends and Colleagues'', John Wiley & Sons, 1964. * Stefan Rozental, ''Schicksalsjahre mit Niels Bohr'', DVA, 1991.
(This is a German translation of Rozental's Danish account ''NB - erindringer om Niels Bohr'' of his years with Niels Bohr, published 1985 in Kopenhagen. No English translation available.)

External links

* http://www.nba.nbi.dk/icos/rozen.htm Biographical Informationen from on the web site of the

Niels Bohr Institute The Niels Bohr Institute (Danish: ''Niels Bohr Institutet'') is a research institute of the University of Copenhagen. The research of the institute spans astronomy, geophysics, nanotechnology, particle physics, quantum mechanics and biophysics ...

Short biography
at the ''Stefan Rozental and foundation'' ( DTU) — in Danish, includes a photo 1903 births 1994 deaths Polish emigrants to Denmark Polish nuclear physicists Leipzig University faculty Jagiellonian University alumni Jagiellonian University faculty 20th-century Polish Jews Scientists from Łódź Jewish physicists {{Poland-scientist-stub