Editing Mark Oliphant (section)

=== Manhattan Project ===
At the University of Birmingham in March 1940, [[Otto Frisch]] and [[Rudolf Peierls]] examined the theoretical issues involved in developing, producing and using [[atomic bomb]]s in a paper that became known as the [[Frisch–Peierls memorandum]]. They considered what would happen to a sphere of pure uranium-235, and found that not only could a [[chain reaction]] occur, but it might require as little as {{convert|1|kg|0}} of uranium-235 to unleash the energy of hundreds of tons of [[TNT]]. The first person they showed their paper to was Oliphant, and he immediately took it to Sir [[Henry Tizard]], the chairman of the Committee for the Scientific Survey of Air Warfare (CSSAW).{{sfn|Gowing|1964|pp=39–41, 407}} As a result, a special subcommittee of the CSSAW known as the [[MAUD Committee]] was created to investigate the matter further. It was chaired by Sir [[George Paget Thomson|George Thomson]], and its original membership included Oliphant, Chadwick, Cockcroft and Moon.{{sfn|Gowing|1964|p=45}} In its final report in July 1941, the MAUD Committee concluded that an atomic bomb was not only feasible, but might be produced as early as 1943.{{sfn|Gowing|1964|p=78}}

[[File:Y-12 Calutron Alpha racetrack.jpg|thumb|The giant Alpha I racetrack at the [[Y-12 National Security Complex]] at [[Oak Ridge, Tennessee]], used for electromagnetic separation.|alt=A large oval-shaped structure]]
Great Britain was at war and authorities there thought that the development of an atomic bomb was urgent, but there was much less urgency in the United States. Oliphant was one of the people who pushed the American program into motion.{{sfn|Rhodes|1986|p=372}} On 5 August 1941, Oliphant flew to the United States  in a [[B-24 Liberator]] bomber, ostensibly to discuss the radar-development program, but was assigned to find out why the United States was ignoring the findings of the MAUD Committee.<ref name="Indiscretion">{{cite journal |title=The Indiscretion of Mark Oliphant: How an Australian Kick-started the American Atomic Bomb Project |first=Darren |last=Holden |journal=Historical Records of Australian Science |date=17 January 2018 |volume=29 |pages=28–35 |doi=10.1071/HR17023 }}</ref> He later recalled: "the minutes and reports had been sent to [[Lyman Briggs]], who was the Director of the Uranium Committee, and we were puzzled to receive virtually no comment. I called on Briggs in Washington [DC], only to find out that this inarticulate and unimpressive man had put the reports in his safe and had not shown them to members of his committee. I was amazed and distressed."<ref>{{cite journal |last=Oliphant |first=Mark |title=The Beginning: Chadwick and the Neutron |journal=[[Bulletin of the Atomic Scientists]] |date=December 1982 |volume=38 |issue=10 |pages=14–18 |issn=0096-3402 |url=https://books.google.com/books?id=jwoAAAAAMBAJ&pg=PA17 |access-date=3 May 2012 |doi=10.1080/00963402.1982.11455816 |bibcode=1982BuAtS..38j..14O |url-access=subscription }}</ref>

Oliphant then met with the Uranium Committee at its meeting in New York on 26 August 1941.<ref name="Indiscretion" /> [[Samuel King Allison|Samuel K. Allison]], a new member of the committee, was an experimental physicist and a protégé of [[Arthur Compton]] at the [[University of Chicago]]. He recalled that Oliphant "came to a meeting and said 'bomb' in no uncertain terms. He told us we must concentrate every effort on the bomb, and said we had no right to work on power plants or anything but the bomb. The bomb would cost 25 million dollars, he said, and Britain did not have the money or the manpower, so it was up to us." Allison was surprised that Briggs had kept the committee in the dark.{{sfn|Rhodes|1986|p=373}} 

Oliphant then travelled to Berkeley, where he met his friend Lawrence on 23 September, giving him a copy of the Frisch–Peierls memorandum. Lawrence had [[Robert Oppenheimer]] check the figures, bringing him into the project for the first time. Oliphant found another ally in Oppenheimer,<ref name="Indiscretion" /> and he not only managed to convince Lawrence and Oppenheimer that an atomic bomb was feasible, but inspired Lawrence to convert his {{convert|37|inch|cm|adj=on}} cyclotron into a giant [[mass spectrometer]] for [[electromagnetic isotope separation]],{{sfn|Hewlett|Anderson|1962|p=44}} a technique Oliphant had pioneered in 1934.<ref name="Electromagnetic separation">{{cite journal |first1=M. L. E. |last1=Oliphant |first2=E. S. |last2=Shire |first3=B. M. |last3=Crowther  |journal=Proceedings of the Royal Society A |title=Separation of the Isotopes of Lithium and Some Nuclear Transformations Observed with them |date=15 October 1934 |volume=146 |issue=859 |pages=922–929 |doi=10.1098/rspa.1934.0197 |bibcode=1934RSPSA.146..922O |doi-access=free }}</ref> [[Leo Szilard]] later wrote, "if Congress knew the true history of the atomic energy project, I have no doubt but that it would create a special medal to be given to meddling foreigners for distinguished services, and that Dr Oliphant would be the first to receive one."{{sfn|Rhodes|1986|p=372}}

[[File:University of Birmingham - Poynting Physics Building - blue plaques group - Oliphant.jpg|thumb|The University of Birmingham – Poynting Physics Building – blue plaque]]
On 26 October 1942, Oliphant embarked from Melbourne, taking Rosa and the children back with him. The wartime sea voyage on the French ''Desirade'' was again a slow one, and they did not reach Glasgow until 28 February 1943.{{sfn|Cockburn|Ellyard|1981|pp=93–94}} He had to leave them behind once more in November 1943 after the British [[Tube Alloys]] effort was merged with the American [[Manhattan Project]] by the [[Quebec Agreement]], and he left for the United States as part of the [[British contribution to the Manhattan Project|British Mission]]. Oliphant was one of the scientists whose services the Americans were most eager to secure. Oppenheimer, who was now the director of the [[Los Alamos Laboratory]] attempted to persuade him to join the team there, but Oliphant preferred to head a team assisting his friend Lawrence at the Radiation Laboratory in Berkeley to develop the electromagnetic [[uranium enrichment]]—a vital but less overtly military part of the project.{{sfn|Cockburn|Ellyard|1981|pp=113–114}}

Oliphant secured the services of fellow Australian physicist [[Harrie Massey]], who had been working for the Admiralty on [[magnetic mines]], along with James Stayers and Stanley Duke, who had worked with him on the [[cavity magnetron]]. This initial group set out for Berkeley in a [[B-24 Liberator]] bomber in November 1943.{{sfn|Cockburn|Ellyard|1981|pp=113–115}} Oliphant became Lawrence's ''de facto'' deputy, and was in charge of the Berkeley Radiation Laboratory when Lawrence was absent.{{sfn|Gowing|1964|pp=256–260}} Although based in Berkeley, he often visited [[Oak Ridge, Tennessee]], where the separation plant was, and was an occasional visitor to Los Alamos.{{sfn|Cockburn|Ellyard|1981|p=183}} He made efforts to involve Australian scientists in the project,<ref name="Binnie">{{cite journal |url=http://royalsoc.org.au/publications/journal_2000_on/139_p1,2_binnie.pdf |journal=Journal and Proceedings of the Royal Society of New South Wales |volume=139 |issue=419–420 |pages=11–22 |year=2006 |issn=0035-9173 |first=Anna |last=Binnie |title=Oliphant, the Father of Atomic Energy |doi=10.5962/p.361572 |s2cid=259734791 |access-date=23 February 2015 |archive-url=https://web.archive.org/web/20160228103540/http://royalsoc.org.au/publications/journal_2000_on/139_p1,2_binnie.pdf |archive-date=28 February 2016 |url-status=live  }}</ref> and had Sir [[David Rivett]], the head of the Council for Scientific and Industrial Research, release Eric Burhop to work on the Manhattan Project.<ref name="Binnie"/><ref>{{cite web |url=http://dfat.gov.au/about-us/publications/historical-documents/Pages/volume-07/4-rivett-to-white.aspx |title=Rivett to White |date=5 January 1944 |publisher=[[Department of Foreign Affairs and Trade (Australia)|Department of Foreign Affairs and Trade]] |access-date=21 April 2018 |archive-url=https://web.archive.org/web/20180421162747/http://dfat.gov.au/about-us/publications/historical-documents/Pages/volume-07/4-rivett-to-white.aspx |archive-date=21 April 2018 |url-status=live  }}</ref> He briefed [[Stanley Bruce]], the [[Australian High Commissioner to the United Kingdom]], on the project, and urged the Australian government to secure Australian uranium deposits.<ref name="Binnie"/><ref>{{cite web |url=http://dfat.gov.au/about-us/publications/historical-documents/Pages/volume-06/258-bruce-to-curtin.aspx |title=Bruce to Curtin |date=16 August 1943 |publisher=[[Department of Foreign Affairs and Trade (Australia)|Department of Foreign Affairs and Trade]] |access-date=21 April 2018 |archive-url=https://web.archive.org/web/20180421162811/http://dfat.gov.au/about-us/publications/historical-documents/Pages/volume-06/258-bruce-to-curtin.aspx |archive-date=21 April 2018 |url-status=live  }}</ref>

A meeting with [[Major general (United States)|Major General]] [[Leslie Groves]], the director of the Manhattan Project, at Berkeley in September 1944, convinced Oliphant that the Americans intended to monopolise nuclear weapons after the war, restricting British research and production to Canada, and not permitting nuclear weapons technology to be shared with Australia. Characteristically, Oliphant bypassed Chadwick, the head of the British Mission, and sent a report direct to [[Wallace Akers]], the head of the [[Tube Alloys]] Directorate in London. Akers summoned Oliphant back to London for consultation. En route, Oliphant met with Chadwick and other members of the British Mission in Washington, where the prospect of resuming an independent British project was discussed. Chadwick was adamant that the cooperation with the Americans should continue, and that Oliphant and his team should remain until the task of building an atomic bomb was finished. Akers sent Chadwick a telegram directing that Oliphant should return to the UK by April 1945.<ref name="On the Oliphant Deign">{{cite journal |title='On the Oliphant Deign, Now to Sound the Blast': How Mark Oliphant Secretly Warned of America's Post-war Intentions of an Atomic Monopoly |first=Darren |last=Holden |journal=Historical Records of Australian Science |volume=29 |issue=2 |pages=130 |date=15 May 2018 |doi=10.1071/HR18008 }}</ref>

Oliphant returned to England in March 1945, and resumed his post as a professor of physics at the University of Birmingham. He was on holiday in Wales with his family when he first heard of the [[atomic bombing of Hiroshima and Nagasaki]].{{sfn|Cockburn|Ellyard|1981|pp=122–124}} He was later to remark that he felt "sort of proud that the bomb had worked, and absolutely appalled at what it had done to human beings". Oliphant became a harsh critic of nuclear weapons and a member of the [[Pugwash Conferences on Science and World Affairs]], saying, "I, right from the beginning, have been terribly worried by the existence of nuclear weapons and very much against their use."<ref name=curiosity /> His wartime work would have earned him a [[Medal of Freedom (1945)|Medal of Freedom]] with Gold Palm, but the Australian government vetoed this honour,<ref name="AAS">{{cite web|title=Australian Academy of Science – Biographical Memoirs – Marcus Laurence Elwin Oliphant|url=http://science.org.au/fellows/memoirs/oliphant.html|access-date=7 March 2013|archive-date=6 August 2013 |archive-url=https://web.archive.org/web/20130806033305/http://www.science.org.au/fellows/memoirs/oliphant.html}}</ref> as government policy at the time was not to confer honours on civilians.{{sfn|Cockburn|Ellyard|1981|p=198}}