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 . Bohr was also a philosopher and a promoter of scientific research . Bohr developed the Bohr model of the atom , in which he proposed that energy levels of electrons are discrete , and that they revolve in discrete , stable orbits around the atomic nucleus , akin to planets around the sun , except that they can jump from one energy level ( or orbit ) to another . Although the Bohr model has been supplanted by other models , its underlying principles remain valid . He conceived the principle of complementarity : that items could be separately analysed in terms of contradictory properties , like behaving as a wave or a stream of particles . The notion of complementarity dominated his thinking on both science and philosophy . Bohr founded the Institute of Theoretical Physics at the University of Copenhagen , now known as the Niels Bohr Institute , which opened in 1920 . Bohr mentored and collaborated with physicists including Hans Kramers , Oskar Klein , George de Hevesy and Werner Heisenberg . He predicted the existence of a new zirconium - like element , which was named hafnium , after the Latin name for Copenhagen , where it was discovered . Later , the element bohrium was named after him . During the 1930s , Bohr helped refugees from Nazism . After Denmark was occupied by the Germans , he met with Heisenberg , who had become the head of the German nuclear energy project . In September 1943 , word reached Bohr that he was about to be arrested by the Germans , and he fled to Sweden . From there , he was flown to Britain , where he joined the British Tube Alloys nuclear weapons project , and was part of the British mission to the Manhattan Project . After the war , Bohr called for international cooperation on nuclear energy . He was involved with the establishment of CERN and the Research Establishment Risø of the Danish Atomic Energy Commission , and became the first chairman of the Nordic Institute for Theoretical Physics in 1957 . Early years . Niels Bohr was born in Copenhagen , Denmark , on 7 October 1885 , the second of three children of Christian Bohr , a professor of physiology at the University of Copenhagen , and Ellen Adler Bohr , who came from a wealthy Danish Jewish family prominent in banking and parliamentary circles . He had an older sister , Jenny , and a younger brother Harald . Jenny became a teacher , while Harald became a mathematician and Olympic footballer who played for the Danish national team at the 1908 Summer Olympics in London . Niels was a passionate footballer as well , and the two brothers played several matches for the Copenhagen - based Akademisk Boldklub , with Niels as goalkeeper . Bohr was educated at Gammelholm Latin School , starting when he was seven . In 1903 , Bohr enrolled as an undergraduate at Copenhagen University . His major was physics , which he studied under Professor Christian Christiansen , the university ' s only professor of physics at that time . He also studied astronomy and mathematics under Professor Thorvald Thiele , and philosophy under Professor Harald Høffding , a friend of his father . In 1905 , a gold medal competition was sponsored by the Royal Danish Academy of Sciences and Letters to investigate a method for measuring the surface tension of liquids that had been proposed by Lord Rayleigh in 1879 . Bohr conducted a series of experiments using his father ' s laboratory in the university ; the university itself had no physics laboratory . To complete his experiments , he had to make his own glassware , creating test tubes with the required elliptical cross - sections . He went beyond the original task , incorporating improvements into both Rayleigh ' s theory and his method . His essay , which he submitted at the last minute , won the prize . He later submitted an improved version of the paper to the Royal Society in London for publication in the " Philosophical Transactions of the Royal Society " . Harald became the first of the two Bohr brothers to earn a Master ' s Degree , which he earned for mathematics in April 1909 . Niels took another nine months to earn his . Students had to submit a thesis on a subject assigned by their supervisor . Bohr ' s supervisor was Christiansen , and the topic he chose was the electron theory of metals . Bohr subsequently elaborated his master ' s thesis into his much larger Doctor of Philosophy ( PhD ) thesis . He surveyed the literature on the subject , settling on a model postulated by Paul Drude and elaborated by Hendrik Lorentz , in which the electrons in a metal are considered to behave like a gas . Bohr extended Lorentz ' s model but was still unable to account for phenomena like the Hall effect , and concluded that electron theory could not fully explain the magnetic properties of metals . The thesis was accepted in April 1911 , and Bohr conducted his formal defence on 13 May . Harald had received his PhD the previous year . In 1910 , Bohr met Margrethe Nørlund , the sister of the mathematician Niels Erik Nørlund . Bohr resigned his membership in the Church of Denmark on 16 April 1912 , and he and Margrethe were married in a civil ceremony at the town hall in Slagelse on 1 August . Years later , his brother Harald similarly left the church before getting married . Niels and Margrethe had six sons . The oldest , Christian , died in a boating accident in 1934 , and another , Harald , died from childhood meningitis . Aage Bohr became a successful physicist , and in 1975 was awarded the Nobel Prize in physics , like his father . Hans Henrik became a physician ; Erik , a chemical engineer ; and Ernest , a lawyer . Like his uncle Harald , Ernest Bohr became an Olympic athlete , playing field hockey for Denmark at the 1948 Summer Olympics in London . Physics . Bohr model . In 1911 , Bohr travelled to England , where he met with J . J . Thomson of the Cavendish Laboratory and Trinity College , Cambridge . He attended lectures on electromagnetism given by James Jeans and Joseph Larmor , and did some research on cathode rays , but failed to impress Thomson . He had more success with Ernest Rutherford from Victoria University of Manchester , whose 1911 Rutherford model of the atom had recently challenged Thomson ' s plum pudding model . Bohr received an invitation to conduct post - doctoral work at Manchester , where he met George de Hevesy and Charles Galton Darwin ( whom Bohr referred to as " the grandson of the real Darwin " ) . Bohr returned to Denmark in July 1912 for his wedding , and travelled around England and Scotland on his honeymoon . On his return , he became a " privatdocent " at the University of Copenhagen , giving lectures on thermodynamics . Martin Knudsen put Bohr ' s name forward for a " docent " , which was approved in July 1913 , and Bohr then began teaching medical students . His three papers , which later became famous as " the Trilogy " , were published in " Philosophical Magazine " in July , September and November of that year . He adapted Rutherford ' s nuclear structure to Max Planck ' s quantum theory and so created his Bohr model of the atom . Taking the 1912 paper by Darwin on the role of electrons in the interaction of alpha particles with a nucleus as his starting point , he advanced the theory of electrons travelling in orbit s around the atom ' s nucleus , with the chemical properties of each element being largely determined by the number of electrons in the outer orbits of its atoms . He introduced the idea that an electron could drop from a higher - energy orbit to a lower one , in the process emitting a quantum of discrete energy . This became a basis for what is now called the old quantum theory . In 1885 , Johann Balmer had come up with his Balmer series to describe the visible spectral line s of a hydrogen atoms : where λ is the wavelength of the absorbed or emitted light and " R " is the Rydberg constant . Balmer ' s formula was corroborated by the discovery of additional spectral lines , but for thirty years , no one could explain why it worked . In the first paper of his Trilogy , Bohr was able to derive it from his model : where " m " is the electron ' s mass , " e " is its charge , " h " is Planck ' s constant and " Z " is the atom ' s atomic number ( 1 for hydrogen ) . One problem was the Pickering series , lines which did not fit Balmer ' s formula . When challenged on this by Alfred Fowler , Bohr replied that they were caused by ionised helium , helium atoms with only one electron . The model was found to work for such ions as well . Many older physicists like Thomson and Rayleigh did not like the Trilogy , but the younger generation , including Ernest Rutherford , David Hilbert , Albert Einstein , Max Born and Arnold Sommerfeld saw it as a breakthrough , and Emil Warburg thought highly of it . Bohr did not enjoy teaching medical students . He decided to return to Manchester , where Rutherford had offered him a job as a reader in place of Darwin , whose tenure had expired . Bohr accepted . He took a leave of absence from the University of Copenhagen , which he started by taking a holiday in Tyrol with his brother Harald and aunt Hanna Adler . There , he visited the University of Göttingen and the Ludwig Maximilian University of Munich , where he met Sommerfeld and conducted seminars on the Trilogy . The First World War broke out while they were in Tyrol , greatly complicating the trip back to Denmark and Bohr ' s subsequent voyage with Margrethe to England , where he arrived in October 1914 . They stayed until July 1916 , by which time he had been appointed to the Chair of Theoretical Physics at the University of Copenhagen , a position created especially for him . His docentship was abolished at the same time , so he still had to teach physics to medical students . New professors were formally introduced to King Christian X , who expressed his delight at meeting such a famous football player . Institute of Physics . In April 1917 , Bohr began a campaign to establish an Institute of Theoretical Physics . He gained the support of the Danish government and the Carlsberg Foundation , and sizeable contributions were also made by industry and private donors , many of them Jewish . Legislation establishing the Institute was passed in November 1918 . Now known as the Niels Bohr Institute , it opened its doors on 3 March 1921 with Bohr as its director . His family moved into an apartment on the first floor . Bohr ' s institute served as a focal point for researchers into quantum mechanics and related subjects in the 1920s and 1930s , when most of the world ' s best known theoretical physicists spent some time in his company . Early arrivals included Hans Kramers from the Netherlands , Oskar Klein from Sweden , George de Hevesy from Hungary , Wojciech Rubinowicz from Poland and Svein Rosseland from Norway . Bohr became widely appreciated as their congenial host and eminent colleague . Klein and Rosseland produced the Institute ' s first paper even before it opened . The Bohr model worked well for hydrogen , but could not explain more complex elements . By 1919 , Bohr was moving away from the idea that electrons orbited the nucleus , and he developed heuristics to describe them . The rare earth elements posed a particular classification problem for chemists , because they were so chemically similar . An important development came in 1924 with Wolfgang Pauli ' s discovery of the Pauli exclusion principle , which put Bohr ' s models on a firm theoretical footing . Bohr was then able to declare that the as - yet - undiscovered element 72 was not a rare earth element , but an element with chemical properties similar to those of zirconium . He was immediately challenged by the French chemist Georges Urbain , who claimed to have discovered a rare earth element 72 , which he called " celtium " . At the Institute in Copenhagen , Dirk Coster and George de Hevesy took up the challenge of proving Bohr right and Urbain wrong . Starting with a clear idea of the chemical properties of the unknown element greatly simplified the search process . They went through samples from Copenhagen ' s Museum of Mineralogy looking for a zirconium - like element , and soon found it . The element , which they named hafnium , " Hafnia " being the Latin name for Copenhagen , turned out to be more common than gold . In 1922 , Bohr was awarded the Nobel Prize in Physics " for his services in the investigation of the structure of atoms and of the radiation emanating from them " . The award thus recognised both the Trilogy and his early leading work in the emerging field of quantum mechanics . For his Nobel lecture , Bohr gave his audience a comprehensive survey of what was then known about the structure of the atom , including the correspondence principle , which he had formulated . The discovery of Compton scattering by Arthur Holly Compton in 1923 convinced most physicists that light was composed of photons , and that energy and momentum were conserved in collisions between electrons and photons . In 1924 , Bohr , Kramers and John C . Slater , an American physicist working at the Institute in Copenhagen , proposed the Bohr - Kramers - Slater theory ( BKS ) . It was more a program than a full physical theory , as the ideas it developed were not worked out quantitatively . BKS theory became the final attempt at understanding the interaction of matter and electromagnetic radiation on the basis of the old quantum theory , in which quantum phenomena were treated by imposing quantum restrictions on a classical wave description of the electromagnetic field . Modelling atomic behaviour under incident electromagnetic radiation using " virtual oscillators " at the absorption and emission frequencies , rather than the ( different ) apparent frequencies of the Bohr orbits , led Max Born , Werner Heisenberg and Kramers to explore different mathematical models . They led to the development of matrix mechanics , the first form of modern quantum mechanics . The BKS theory also generated discussion of , and renewed attention to , difficulties in the foundations of the old quantum theory . The most provocative element of BKS – that momentum and energy would not necessarily be conserved in each interaction , but only statistically – was soon shown to be in conflict with experiments conducted by Walter Bothe and Hans Geiger . In the light of these results , Bohr informed Darwin , " there is nothing else to do than to give our revolutionary efforts as honourable a funeral as possible . " Quantum mechanics . The introduction of spin by George Uhlenbeck and Samuel Goudsmit in November 1925 was a milestone . The next month , Bohr travelled to Leiden to attend celebrations of the 50th anniversary of Hendrick Lorentz receiving his doctorate . When his train stopped in Hamburg , he was met by Wolfgang Pauli and Otto Stern , who asked for his opinion of the spin theory . Bohr pointed out that he had concerns about the interaction between electrons and magnetic fields . When he arrived in Leiden , Paul Ehrenfest and Albert Einstein informed Bohr that Einstein had resolved this problem using relativity . Bohr then had Uhlenbeck and Goudsmit incorporate this into their paper . Thus , when he met Werner Heisenberg and Pascual Jordan in Göttingen on the way back , he had become , in his own words , " a prophet of the electron magnet gospel " . Heisenberg first came to Copenhagen in 1924 , but returned to Göttingen in June 1925 . When Kramers left the Institute in 1926 to take up a chair as professor of theoretical physics at the Utrecht University , Bohr arranged for Heisenberg to return and take Kramers ' s place as a " lektor " at the University of Copenhagen . Heisenberg worked in Copenhagen as a university lecturer and assistant to Bohr from 1926 to 1927 , and it was there in 1925 that Heisenberg developed the mathematical foundations of quantum mechanics . When he showed his results to Max Born in Göttingen , Born realised that they could best be expressed using matrices . This work attracted the attention of the British physicist Paul Dirac , who came to Copenhagen for six months in September 1926 . Austrian physicist Erwin Schrödinger also visited in 1926 . His attempt at explaining quantum physics in classical terms using wave mechanics impressed Bohr , who believed it contributed " so much to mathematical clarity and simplicity that it represents a gigantic advance over all previous forms of quantum mechanics " . Bohr was now convinced that light behaved like both waves and particles , and in 1927 , experiments confirmed the de Broglie hypothesis that matter ( like electrons ) also behaved like waves . He conceived the philosophical principle of complementarity : that items could have apparently mutually exclusive properties , such as being a wave or a stream of particles , depending on the experimental framework . He felt that that it was not fully understood by professional philosophers . In Copenhagen in 1927 Heisenberg developed his uncertainty principle , which Bohr embraced . In a paper he presented at the Volta Conference at Como in September 1927 , he demonstrated that the uncertainty principle could be derived from classical arguments , without quantum terminology or matrices . Einstein preferred the determinism of classical physics over the probabilistic new quantum physics to which he himself had contributed . Philosophical issues that arose from the novel aspects of quantum mechanics became widely celebrated subjects of discussion . Einstein and Bohr had good - natured arguments over such issues throughout their lives . In 1914 , Carl Jacobsen , the heir to Carlsberg breweries , bequeathed his mansion to be used for life by the Dane who had made the most prominent contribution to science , literature or the arts , as an honorary residence ( ) . Harald Høffding had been the first occupant , and upon his death in July 1931 , the Royal Danish Academy of Sciences and Letters gave Bohr occupancy . He and his family moved there in 1932 . He was elected president of the Academy on 17 March 1939 . By 1929 , the phenomenon of beta decay prompted Bohr to again suggest that the law of conservation of energy be abandoned , but Enrico Fermi ' s hypothetical neutrino and the subsequent 1932 discovery of the neutron provided another explanation . This prompted Bohr to create a new theory of the compound nucleus in 1936 , which explained how neutrons could be captured by the nucleus . In this model , the nucleus could be deformed like a drop of liquid . He worked on this with a new collaborator , the Danish physicist Fritz Kalckar , who died suddenly in 1938 . The discovery of nuclear fission by Lise Meitner and Otto Hahn in December 1938 generated intense interest among physicists . Bohr brought the news to the United States where he opened the Fifth Washington Conference on Theoretical Physics with Fermi on 26 January 1939 . When Bohr told George Placzek that this resolved all the mysteries of transuranic elements , Placzek told him that one remained : the neutron capture energies of uranium did not match those of its decay . Bohr thought about it for a few minutes and then announced to Placzek , Leon Rosenfeld and John Wheeler that " I have understood everything . " Based on his liquid drop model of the nucleus , Bohr concluded that it was the uranium - 235 isotope and not the more abundant uranium - 238 that was primarily responsible for fission . In April 1940 , John R . Dunning demonstrated that Bohr was correct . In the meantime , Bohr and Wheeler developed a theoretical treatment which they published in a September 1939 paper on " The Mechanism of Nuclear Fission " . Philosophy . Bohr read the 19th century Danish Christian existentialist philosopher , Søren Kierkegaard . Richard Rhodes argued in " The Making of the Atomic Bomb " that Bohr was influenced by Kierkegaard through Høffding . Bohr ' s disagreements with the philosopher mostly stemmed from Bohr ' s atheism . In 1909 , Bohr sent his brother Kierkegaard ' s " Stages on Life ' s Way " as a birthday gift . In the enclosed letter , Bohr wrote , " It is the only thing I have to send home ; but I do not believe that it would be very easy to find anything better . . . I even think it is one of the most delightful things I have ever read . " Bohr enjoyed Kierkegaard ' s language and literary style , but mentioned that he had some disagreement with Kierkegaard ' s philosophy . There has been some dispute over the extent to which Kierkegaard influenced Bohr ' s philosophy and science . David Favrholdt argued that Kierkegaard had minimal influence over Bohr ' s work , taking Bohr ' s statement about disagreeing with Kierkegaard at face value , while Jan Faye argued that one can disagree with the content of a theory while accepting its general premises and structure . Nazism and Second World War . The rise of Nazism in Germany prompted many scholars to flee their countries . Most of the refugees were Jewish , and others were non - Jewish opponents of the Nazi regime . In 1933 , the Rockefeller Foundation created a fund to help support refugee academics , and Bohr discussed this programme with the President of the Rockefeller Foundation , Max Mason , in May 1933 during a visit to the United States . Bohr offered the refugees temporary jobs at the Institute , provided them with financial support , arranged for them to be awarded fellowships from the Rockefeller Foundation , and ultimately found them places at institutions around the world . Those that he helped included Guido Beck , Felix Bloch , James Franck , George de Hevesy , Otto Frisch , Hilde Levi , Lise Meitner , George Placzek , Eugene Rabinowitch , Stefan Rozental , Erich Schneider , Edward Teller , Arthur von Hippel and Victor Weisskopf . In April 1940 , early in the Second World War , Nazi Germany invaded and occupied Denmark . To prevent the Germans from discovering Max von Laue ' s and James Franck ' s gold Nobel medals , Bohr had de Hevesy dissolve them in acid . In this form , they were stored on a shelf at the Institute until after the war , when the gold was precipitated and the medals re - struck by the Nobel Foundation . Bohr kept the Institute running , but all the foreign scholars departed . Meeting with Heisenberg . Bohr was aware of the possibility of using uranium - 235 to construct an atomic bomb , referring to it in lectures in Britain and Denmark shortly before and after the war started , but he did not believe that it was technically feasible to extract a sufficient quantity of uranium - 235 . In September 1941 , Heisenberg , who had become head of the German nuclear energy project , visited Bohr in Copenhagen . During a private moment outside with Bohr , Heisenberg began to address nuclear energy , morality and the war . Bohr seems to have reacted by terminating the conversation abruptly while not giving Heisenberg hints about his own opinions . Ivan Supek , one of Heisenberg ' s students and friends , claimed that the main figure of the meeting was Carl Friedrich von Weizsäcker , who tried to persuade Bohr to mediate peace between Britain and Germany . In 1957 , Heisenberg wrote to Robert Jungk , who was then working on the book " " . Heisenberg explained that he had visited Copenhagen to communicate to Bohr the views of several German scientists , that production of a nuclear weapon was possible with great efforts , and this raised enormous responsibilities on the world ' s scientists on both sides . When Bohr saw Jungk ' s depiction in the Danish translation of the book , he drafted ( but never sent ) a letter to Heisenberg , stating that he never understood the purpose of Heisenberg ' s visit , was shocked by Heisenberg ' s opinion that Germany would win the war , and that atomic weapons could be decisive . Michael Frayn ' s play " Copenhagen " ( 1998 ) explored what might have happened at the 1941 meeting between Heisenberg and Bohr . Manhattan Project . In September 1943 , word reached Bohr and his brother Harald that they were about to be arrested by the Germans . The Danish resistance helped Bohr and his wife escape by sea to Sweden on 29 September . The next day , Bohr persuaded King Gustav V of Sweden to make public Sweden ' s willingness to provide asylum to Jewish refugees . On 2 October 1943 , Swedish radio broadcast that Sweden was ready to offer asylum , and the mass rescue of the Danish Jews by their countrymen followed swiftly thereafter . Some historians claim that Bohr ' s actions led directly to the mass rescue , while others say that , though Bohr did all that he could for his countrymen , his actions were not a decisive influence on the wider events . Eventually , over 7 , 000 Danish Jews escaped to Sweden . When the news of Bohr ' s escape reached Britain , Lord Cherwell sent a telegram to Bohr asking him to come to Britain . Bohr arrived in Scotland on 6 October in a De Havilland Mosquito operated by British Overseas Airways Corporation . The Mosquitos were unarmed high - speed bomber aircraft that had been converted to carry small , valuable cargoes or important passengers . By flying at high speed and high altitude , they could cross German - occupied Norway , and yet avoid German fighters . Bohr , equipped with parachute , flying suit and oxygen mask , spent the three - hour flight lying on a mattress in the aircraft ' s bomb bay . During the flight , Bohr did not wear his flying helmet as it was too small , and consequently did not hear the pilot ' s intercom instruction to turn on his oxygen supply when the aircraft climbed to high altitude to overfly Norway . He passed out from oxygen starvation and only revived when the aircraft descended to lower altitude over the North Sea . Bohr ' s son Aage followed his father to Britain on another flight a week later , and became his personal assistant . Bohr was warmly received by James Chadwick and Sir John Anderson , but for security reasons Bohr was kept out of sight . He was given an apartment at St James ' Palace and an office with the British Tube Alloys nuclear weapons development team . Bohr was astonished at the amount of progress that had been made . Chadwick arranged for Bohr to visit the United States as a Tube Alloys consultant , with Aage as his assistant . On 8 December 1943 , Bohr arrived in Washington , D . C . , where he met with the director of the Manhattan Project , Brigadier General Leslie R . Groves , Jr . He visited Einstein and Pauli at the Institute for Advanced Study in Princeton , New Jersey , and went to Los Alamos in New Mexico , where the nuclear weapons were being designed . For security reasons , he went under the name of " Nicholas Baker " in the United States , while Aage became " James Baker " . Bohr did not remain at Los Alamos , but paid a series of extended visits over the course of the next two years . Robert Oppenheimer credited Bohr with acting " as a scientific father figure to the younger men " , most notably Richard Feynman . Bohr is quoted as saying , " They didn ' t need my help in making the atom bomb . " Oppenheimer gave Bohr credit for an important contribution to the work on modulated neutron initiator s . " This device remained a stubborn puzzle , " Oppenheimer noted , " but in early February 1945 Niels Bohr clarified what had to be done . " Bohr recognised early that nuclear weapons would change international relations . In April 1944 , he received a letter from Peter Kapitza , written some months before when Bohr was in Sweden , inviting him to come to the Soviet Union . The letter convinced Bohr that the Soviets were aware of the Anglo - American project , and would strive to catch up . He sent Kapitza a non - committal response , which he showed to the authorities in Britain before posting . Bohr met with Churchill on 16 May 1944 , but found that " we did not speak the same language " . Churchill disagreed with the idea of openness towards the Russians to the point that he wrote in a letter : " It seems to me Bohr ought to be confined or at any rate made to see that he is very near the edge of mortal crimes . " Oppenheimer suggested that Bohr visit President Franklin D . Roosevelt to convince him that the Manhattan Project should be shared with the Soviets in the hope of speeding up its results . Bohr ' s friend , Supreme Court Justice Felix Frankfurter , informed President Roosevelt about Bohr ' s opinions , and a meeting between them took place on 26 August 1944 . Roosevelt suggested that Bohr return to the United Kingdom to try to win British approval . When Churchill and Roosevelt met at Hyde Park on 19 September 1944 , they rejected the idea of informing the world about the project , and the aide - mémoire of their conversation contained a rider that " enquiries should be made regarding the activities of Professor Bohr and steps taken to ensure that he is responsible for no leakage of information , particularly to the Russians . " In June 1950 , Bohr addressed an " Open Letter " to the United Nations calling for international cooperation on nuclear energy . In the 1950s , after the Soviet Union ' s first nuclear weapon test , the International Atomic Energy Agency was created along the lines of Bohr ' s suggestion . In 1957 he received the first ever Atoms for Peace Award . Later years . With the war ended , Bohr returned to Copenhagen on 25 August 1945 , and was re - elected President of the Royal Danish Academy of Arts and Sciences on 21 September . At a memorial meeting of the Academy on 17 October 1947 for King Christian X , who had died in April , the new king , Frederick IX , announced that he was conferring the Order of the Elephant on Bohr . This award was normally awarded only to royalty and heads of state , but the king said that it honoured not just Bohr personally , but Danish science . Bohr designed his own coat of arms which featured a taijitu ( symbol of yin and yang ) and a motto in , " opposites are complementary " . The Second World War demonstrated that science , and physics in particular , now required considerable financial and material resources . To avoid a brain drain to the United States , twelve European countries banded together to create CERN , a research organisation along the lines of the national laboratories in the United States , designed to undertake big science projects beyond the resources of any one of them alone . Questions soon arose regarding the best location for the facilities . Bohr and Kramers felt that the Institute in Copenhagen would be the ideal site . Pierre Auger , who organised the preliminary discussions , disagreed ; he felt that both Bohr and his Institute were past their prime , and that Bohr ' s presence would overshadow others . After a long debate , Bohr pledged his support to CERN in February 1952 , and Geneva was chosen as the site in October . The CERN Theory Group was based in Copenhagen until their new accommodation in Geneva was ready in 1957 . Victor Weisskopf , who later became the Director General of CERN , summed up Bohr ' s role , saying that " there were other personalities who started and conceived the idea of CERN . The enthusiasm and ideas of the other people would not have been enough , however , if a man of his stature had not supported it . " Meanwhile , Scandinavian countries formed the Nordic Institute for Theoretical Physics in 1957 , with Bohr as its chairman . He was also involved with the founding of the Research Establishment Risø of the Danish Atomic Energy Commission , and served as its first chairman from February 1956 . Bohr died of heart failure at his home in Carlsberg on 18 November 1962 . He was cremated , and his ashes were buried in the family plot in the Assistens Cemetery in the Nørrebro section of Copenhagen , along with those of his parents , his brother Harald , and his son Christian . Years later , his wife ' s ashes were also interred there . On 7 October 1965 , on what would have been his 80th birthday , the Institute was officially renamed to what it had been called unofficially for many years : the Niels Bohr Institute . Legacy . Bohr received numerous honours and accolades . In addition to the Nobel Prize , he received the Hughes Medal in 1921 , the Matteucci Medal in 1923 , the Franklin Medal in 1926 , the Copley Medal in 1938 , the Order of the Elephant in 1947 , the Atoms for Peace Award in 1957 and the Sonning Prize in 1961 . The Bohr model ' s semicentennial was commemorated in Denmark on 21 November 1963 with a postage stamp depicting Bohr , the hydrogen atom and the formula for the difference of any two hydrogen energy levels : formula _ 3 . Several other countries have also issued postage stamps depicting Bohr . In 1997 , the Danish National Bank began circulating the 500 - krone banknote with the portrait of Bohr smoking a pipe . An asteroid , 3948 Bohr , was named after him , as was a lunar crater , and bohrium , the chemical element with atomic number 107 .