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De: BARILOCHENSE6999  (Mensaje original) Enviado: 09/02/2025 14:35

Mark Oliphant

 
 
 
Mark Oliphant
Oliphant in 1939
Born
Marcus Laurence Elwin Oliphant

8 October 1901
Died 14 July 2000 (aged 98)
Education
Known for
Awards
Scientific career
Institutions
Thesis The Neutralization of Positive Ions at Metal Surfaces, and the Emission of Secondary Electrons  (1929)
Doctoral advisor Ernest Rutherford
Doctoral students
 
 
27th Governor of South Australia
In office
1 December 1971 – 30 November 1976
Monarch Elizabeth II
Premier Don Dunstan
Lieutenant Governor
Preceded by Sir James Harrison
Succeeded by Sir Douglas Nicholls
Personal details
Political party Australia Party (until 1977)
Australian Democrats (from 1977)
 

Sir Marcus Laurence Elwin OliphantACKBEFRSFAAFTSE (8 October 1901 – 14 July 2000) was an Australian physicist and humanitarian who played an important role in the first experimental demonstration of nuclear fusion and in the development of nuclear weapons.

Born and raised in AdelaideSouth Australia, Oliphant graduated from the University of Adelaide in 1922. He was awarded an 1851 Exhibition Scholarship in 1927 on the strength of the research he had done on mercury, and went to England, where he studied under Sir Ernest Rutherford at the University of Cambridge's Cavendish Laboratory. There, he used a particle accelerator to fire heavy hydrogen nuclei (deuterons) at various targets. He discovered the respective nuclei of helium-3 (helions) and of tritium (tritons). He also discovered that when they reacted with each other, the particles that were released had far more energy than they started with. Energy had been liberated from inside the nucleus, and he realised that this was a result of nuclear fusion.

Oliphant left the Cavendish Laboratory in 1937 to become the Poynting Professor of Physics at the University of Birmingham. He attempted to build a 60-inch (150 cm) cyclotron at the university, but its completion was postponed by the outbreak of the Second World War in Europe in 1939. He became involved with the development of radar, heading a group at the University of Birmingham that included John Randall and Harry Boot. They created a radical new design, the cavity magnetron, that made microwave radar possible. Oliphant also formed part of the MAUD Committee, which reported in July 1941, that an atomic bomb was not only feasible, but might be produced as early as 1943. Oliphant was instrumental in spreading the word of this finding in the United States, thereby starting what became the Manhattan Project. Later in the war, he worked on it with his friend Ernest Lawrence at the Radiation Laboratory in Berkeley, California, developing electromagnetic isotope separation, which provided the fissile component of the Little Boy atomic bomb used in the atomic bombing of Hiroshima in August 1945.

After the war, Oliphant returned to Australia as the first director of the Research School of Physical Sciences and Engineering at the new Australian National University (ANU), where he initiated the design and construction of the world's largest (500 megajoule) homopolar generator. He retired in 1967, but was appointed Governor of South Australia on the advice of Premier Don Dunstan. He became the first South Australian-born governor of South Australia. He assisted in the founding of the Australian Democrats political party, and he was the chairman of the meeting in Melbourne in 1977, at which the party was launched. Late in life he witnessed his wife, Rosa, suffer before her death in 1987, and he became an advocate for voluntary euthanasia. He died in Canberra in 2000.

Early life

[edit]

Marcus "Mark" Laurence Elwin Oliphant was born on 8 October 1901 in Kent Town, a suburb of Adelaide. His father was Harold George "Baron" Olifent,[1] a civil servant with the South Australian Engineering and Water Supply Department and part-time lecturer in economics with the Workers' Educational Association.[2][3] His mother was Beatrice Edith Fanny Oliphant, née Tucker, an artist.[4][5] He was named after Marcus Clarke, the Australian author, and Laurence Oliphant, the British traveller and mystic. Most people called him Mark; this became official when he was knighted in 1959.[6]

He had four younger brothers: Roland, Keith, Nigel and Donald; all were registered at birth with the surname Olifent. His grandfather, Harry Smith Olifent (7 November 1848 – 30 January 1916) was a clerk at the Adelaide GPO, and his great-grandfather James Smith Olifent (c. 1818 – 21 January 1890) and his wife Eliza (c. 1821 – 18 October 1881) left their native Kent for South Australia aboard the barque Ruby, arriving in March 1854. He would later be appointed Superintendent of the Adelaide Destitute Asylum, and Eliza Olifent was appointed Matron of the establishment in 1865.[7] Mark's parents were Theosophists, and as such may have refrained from eating meat. Marcus became a lifelong vegetarian while a boy, after witnessing the slaughter of pigs on a farm.[8] He was found to be completely deaf in one ear and he needed glasses for severe astigmatism and short-sightedness.[9]

Oliphant was first educated at primary schools in Goodwood and Mylor, after the family moved there in 1910.[10] He attended Unley High School in Adelaide, and, for his final year in 1918, Adelaide High School.[11] After graduation he failed to obtain a bursary to attend university, so he took a job with S. Schlank & Co., an Adelaide manufacturing jeweller noted for medallions. He then secured a cadetship with the State Library of South Australia, which allowed him to take courses at the University of Adelaide at night.[12]

In 1919, Oliphant began studying at the University of Adelaide. At first he was interested in a career in medicine, but later in the year, Kerr Grant, the physics professor, offered him a cadetship in the Physics Department. It paid 10 shillings a week (equivalent to AUD$89 in 2022), the same amount that Oliphant received for working at the State Library, but it allowed him to take any university course that did not conflict with his work for the department.[13] He received his Bachelor of Science (BSc) degree in 1921 and then did honours in 1922, supervised by Grant.[14] Roy Burdon, who acted as head of the department when Grant went on sabbatical in 1925, worked with Oliphant to produce two papers in 1927 on the properties of mercury, "The Problem of the Surface Tension of Mercury and the Action of Aqueous Solutions on a Mercury Surface"[15] and "Adsorption of Gases on the Surface of Mercury".[16] Oliphant later recalled that Burdon taught him "the extraordinary exhilaration there was in even minor discoveries in the field of physics".[17]

Oliphant married Rosa Louise Wilbraham, who was from Adelaide, on 23 May 1925. The two had known each other since they were teenagers. He made Rosa's wedding ring in the laboratory from a gold nugget from the Coolgardie Goldfields that his father had given him.[18]



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Cavendish Laboratory

[edit]

In 1925, Oliphant heard a speech given by the New Zealand physicist Sir Ernest Rutherford, and he decided he wanted to work for him – an ambition that he fulfilled by earning a position at the Cavendish Laboratory at the University of Cambridge in 1927.[18] He applied for an 1851 Exhibition Scholarship on the strength of the research he had done on mercury with Burdon. It came with a living allowance of £250 per annum (equivalent to AUD$45,000 in 2022). When word came through that he had been awarded a fellowship, he wired Rutherford and Trinity College, Cambridge. Both accepted him.[19]

The Cavendish Laboratory was the home of some of the great discoveries in physics. It was founded in 1874 by the Duke of Devonshire (Cavendish was his family name), and its first professor was James Clerk Maxwell.[20]

Rutherford's Cavendish Laboratory was carrying out some of the most advanced research into nuclear physics in the world at the time. Oliphant was invited to afternoon tea by Rutherford and Lady Rutherford. He soon met other researchers at the Cavendish Laboratory, including Patrick BlackettEdward BullardJames ChadwickJohn CockcroftCharles EllisPeter KapitzaEgon BretscherPhilip Moon and Ernest Walton. There were two fellow Australians: Harrie Massey and John Keith Roberts. Oliphant would become especially close friends with Cockcroft. The laboratory had considerable talent but little money to spare, and tended to use a "string and sealing wax" approach to experimental equipment.[21] Oliphant had to buy his own equipment, at one point spending £24 (equivalent to AUD$2,200 in 2022) of his allowance on a vacuum pump.[22]

Oliphant submitted his PhD thesis on The Neutralization of Positive Ions at Metal Surfaces, and the Emission of Secondary Electrons in December 1929.[23] For his viva, he was examined by Rutherford and Ellis. Receiving his degree was the attainment of a major life goal, but it also meant the end of his 1851 Exhibition Scholarship. Oliphant secured an 1851 Senior Studentship, of which there were five awarded each year. It came with a living allowance of £450 per annum (equivalent to A$80,000 in 2022) for two years, with the possibility of a one-year extension in exceptional circumstances, which Oliphant was also awarded.[24]

A son, Geoffrey Bruce Oliphant, was born 6 October 1930,[25] but he died of meningitis on 5 September 1933. He was interred in an unmarked grave in the Ascension Parish Burial Ground in Cambridge, alongside Timothy Cockcroft, the infant son of Sir John and Lady Elizabeth Cockcroft, who had died the year before. Unable to have more children, the Oliphants adopted a four-month-old boy, Michael John, in 1936,[26] and a daughter, Vivian, in 1938.[27]

Sir Ernest Rutherford's laboratory, 1926

In 1932 and 1933, the scientists at the Cavendish Laboratory made a series of ground-breaking discoveries. Cockcroft and Walton bombarded lithium with high energy protons and succeeded in transmuting it into energetic nuclei of helium. This was one of the earliest experiments to change the atomic nucleus of one element to another by artificial means. Chadwick then devised an experiment that discovered a new, uncharged particle with roughly the same mass as the proton: the neutron. In 1933, Blackett discovered tracks in his cloud chamber that confirmed the existence of the positron and revealed the opposing spiral traces of positron–electron pair production.[28]

Oliphant followed up the work by constructing a particle accelerator that could fire protons with up to 600,000 electronvolts of energy. He soon confirmed the results of Cockcroft and Walton on the artificial disintegration of the nucleus and positive ions. He produced a series of six papers over the following two years.[29] In 1933, the Cavendish Laboratory received a gift from the American physical chemist Gilbert N. Lewis of a few drops of heavy water. The accelerator was used to fire heavy hydrogen nuclei (deuterons, which Rutherford called diplons) at various targets. Working with Rutherford and others, Oliphant thereby discovered the nuclei of helium-3 (helions) and tritium (tritons).[30][31][32][33]

Oliphant used electromagnetic separation to separate the isotopes of lithium.[34] He was the first to experimentally demonstrate nuclear fusion. He found that when deuterons reacted with nuclei of helium-3, tritium or with other deuterons, the particles that were released had far more energy than they started with. Binding energy had been liberated from inside the nucleus.[35][36] Following Arthur Eddington's 1920 prediction that energy released by fusing small nuclei together could provide the energy source that powers the stars,[37] Oliphant speculated that nuclear fusion reactions might be what powered the sun.[30] With its higher cross section, the deuterium–tritium nuclear fusion reaction became the basis of a hydrogen bomb.[17] Oliphant had not foreseen this development:

... we had no idea whatever that this would one day be applied to make hydrogen bombs. Our curiosity was just curiosity about the structure of the nucleus of the atom, and the discovery of these reactions was purely, as the Americans would put it, coincidental.[17]

In 1934, Cockcroft arranged for Oliphant to become a fellow of St John's College, Cambridge, which paid about £600 a year. When Chadwick left the Cavendish Laboratory for the University of Liverpool in 1935, Oliphant and Ellis both replaced him as Rutherford's assistant director for research. The job came with a salary of £600 (equivalent to AUD$131,000 in 2022).[38] With the money from St John's, this gave him a comfortable income.[23] Oliphant soon fitted out a new accelerator laboratory with a 1.23 MeV generator at a cost of £6,000 (equivalent to AUD$1,310,000 in 2022) while he designed an even larger 2 MeV generator.[39] He was the first to conceive of the proton synchrotron, a new type of cyclic particle accelerator.[40] In 1937, he was elected to the Royal Society. When he died he was its longest-serving fellow.[23]

University of Birmingham

[edit]
The Poynting Physics building at the University of Birmingham. Its mode of construction helped give rise to the phrase "redbrick university".[27]

Samuel Walter Johnson Smith's imminent mandatory retirement at age 65 prompted a search for a new Poynting Professor of Physics at the University of Birmingham.[41] The university wanted not just a replacement, but a well-known name, and was willing to spend lavishly in order to build up nuclear physics expertise at Birmingham.[42] Neville Moss, its Professor of Mining Engineering and the Dean of its Faculty of Science approached Oliphant, who presented his terms. In addition to his salary of £1,300 (equivalent to AUD$270,000 in 2022), he wanted the university to spend £2,000 (equivalent to A$415,000 in 2022) to upgrade the laboratory, and another £1,000 per annum (equivalent to A$208,000 in 2022) on it. And he did not wish to start until October 1937, to enable him to wrap up his work at the Cavendish Laboratory. Moss agreed to Oliphant's terms.[41]

To obtain funding for the 60-inch (150 cm) cyclotron that he wanted, Oliphant wrote to the British prime minister, Neville Chamberlain, who was from Birmingham. Chamberlain took up the matter with his friend Lord Nuffield, who provided £60,000 (equivalent to AUD$12,000,000 in 2022) for the project, enough for the cyclotron, a new building to house it, and a trip to Berkeley, California, so Oliphant could confer with Ernest Lawrence, the inventor of the cyclotron. Lawrence supported the project, sending Oliphant the plans of the 60-inch (150 cm) cyclotron that he was constructing at Berkeley, and inviting Oliphant to visit him at the Radiation Laboratory.[43]

Oliphant sailed for New York on 10 December 1938, and met Lawrence in Berkeley. The two men got along very well, dining at Trader Vic's in Oakland. Oliphant was aware of the problems in building cyclotrons encountered by Chadwick at the University of Liverpool and Cockcroft at the Cavendish Laboratory, and intended to avoid these and get his cyclotron built on time and on budget by following Lawrence's specifications as closely as possible. He hoped that it would be running by Christmas 1939, but the outbreak of the Second World War quashed his hopes.[43] The Nuffield Cyclotron would not be completed until after the war.[44]

Radar

[edit]
An anode of the original cavity magnetron developed by John Randall and Harry Boot at Birmingham University

In 1938, Oliphant became involved with the development of radar, then still a secret. While visiting prototype radar stations, he realised that shorter-wavelength radio waves were needed urgently, especially if there was to be any chance of building a radar set small enough to fit into an aircraft. In August 1939, he took a small group to Ventnor, on the Isle of Wight, to examine the Chain Home system first hand. He obtained a grant from the Admiralty to develop radar systems with wavelengths less than 10 centimetres (4 in); the best available at the time was 150 centimetres (60 in).[45]

Oliphant's group at Birmingham worked on developing two promising devices, the klystron and the magnetron. Working with James Sayers, Oliphant managed to produce an improved version of the klystron capable of generating 400W. Meanwhile, two more members of his Birmingham team, John Randall and Harry Boot, worked on a radical new design, a cavity magnetron. By February 1940, they had an output of 400W with a wavelength of 9.8 centimetres (3.9 in), just the kind of short wavelengths needed for good airborne radars. The magnetron's power was soon increased a hundred-fold, and Birmingham concentrated on magnetron development. The first operational magnetrons were delivered in August 1941. This invention was one of the key scientific breakthroughs during the war and played a major part in defeating the German U-boats, intercepting enemy bombers, and in directing Allied bombers.[46]

In 1940, the Fall of France, and the possibility that Britain might be invaded, prompted Oliphant to send his wife and children to Australia. The Fall of Singapore in February 1942 led him to offer his services to John Madsen, the Professor of Electrical Engineering at the University of Sydney, and the head of the Radiophysics Laboratory at the Council for Scientific and Industrial Research, which was responsible for developing radar.[46][47] He embarked from Glasgow for Australia on QSMV Dominion Monarch on 20 March. The voyage, part of a 46-ship convoy, was a slow one, with the convoy frequently zigzagging to avoid U-boats, and the ship did not reach Fremantle until 27 May.[48]

The Australians were already preparing to produce radar sets locally. Oliphant persuaded Professor Thomas Laby to release Eric Burhop and Leslie Martin from their work on optical munitions to work on radar, and they succeeded in building a cavity magnetron in their laboratory at the University of Melbourne in May 1942.[49] Oliphant worked with Martin on the process of moving the magnetrons for the laboratory to the production line.[50] Over 2,000 radar sets were produced in Australia during the war.[51]


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Manhattan Project

[edit]

At the University of Birmingham in March 1940, Otto Frisch and Rudolf Peierls examined the theoretical issues involved in developing, producing and using atomic bombs 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 1 kilogram (2 lb) 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).[52] 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 Thomson, and its original membership included Oliphant, Chadwick, Cockcroft and Moon.[53] 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.[54]

A large oval-shaped structureThe giant Alpha I racetrack at the Y-12 National Security Complex at Oak Ridge, Tennessee, used for electromagnetic separation.

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.[55] 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.[56] 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."[57]

Oliphant then met with the Uranium Committee at its meeting in New York on 26 August 1941.[56] 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.[58]

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,[56] and he not only managed to convince Lawrence and Oppenheimer that an atomic bomb was feasible, but inspired Lawrence to convert his 37-inch (94 cm) cyclotron into a giant mass spectrometer for electromagnetic isotope separation,[59] a technique Oliphant had pioneered in 1934.[34] 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."[55]

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.[60] 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 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.[61]

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.[62] Oliphant became Lawrence's de facto deputy, and was in charge of the Berkeley Radiation Laboratory when Lawrence was absent.[63] Although based in Berkeley, he often visited Oak Ridge, Tennessee, where the separation plant was, and was an occasional visitor to Los Alamos.[64] He made efforts to involve Australian scientists in the project,[65] and had Sir David Rivett, the head of the Council for Scientific and Industrial Research, release Eric Burhop to work on the Manhattan Project.[65][66] 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.[65][67]

A meeting with 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.[68]

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.[69] 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."[17] His wartime work would have earned him a Medal of Freedom with Gold Palm, but the Australian government vetoed this honour,[23] as government policy at the time was not to confer honours on civilians.[70]


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Oppenheimer, Oliphant and the human chain reaction behind the first atomic bombs

Fri 4 Aug 2023Friday 4 August 2023
The glow of a nuclear blast.

The so-called Trinity test — the detonation of the world's first nuclear weapon, in New Mexico, in July 1945. (US Department of Energy: Jack Aeby)

Link copied

Among the elegies for the inhabitants of Hiroshima, there exists an especially arresting and resonant example authored by an Australian poet.

Reflecting on the impact of the blast on one of its young victims, Bruce Dawe recounted the morning of August 6, 1945, when a "single plane loosed a single bomb" and the city below — but also the very prospect of posterity — "became suddenly phantasmal".

A human shadow left by a nuclear blast.

A suspected "human shadow" left by the vaporisation of a person at Hiroshima. (Wikimedia Commons: Matsuhige Yoshito)

When humans first split atoms, they also split history.

"The atomic bomb," wrote its chief developer, the physicist J. Robert Oppenheimer, "has led us up those last few steps to the mountain pass; and beyond there is a different country".

That different country is the age in which we now live.

Among the chroniclers who described its dawn were some astute enough to notice that fission had produced unforeseen fissures: with the advent of the bomb, human knowledge itself seemed to fracture, with science on one side and conscience on the other.

Oppenheimer was perhaps an exception to this dichotomy, and combined academic interests from both sides of the divide — erudite, sensitive and cultured, he was, in some respects, an unlikely atomic father figure.

Oppenheimer's name is currently on many a movie-goer's lips, thanks to Christopher Nolan's latest effort to render physics a suitable subject for the big screen.

White man wearing a blue shirt, dark grey suit, hat and tie walks along an empty street at twilight.

Cillian Murphy stars as the eponymous central character in the Christopher Nolan movie Oppenheimer. (Supplied: Universal)

But one episode absent from the blockbuster is the meeting, with an Australian scientist, that got Oppenheimer involved with the bomb in the first place.

'The birth of the Manhattan Project'

History teems with chance encounters — instances in which human atoms collide with other human atoms, sometimes causing chain reactions.

The meeting between Oppenheimer and Adelaide-born physicist Mark Oliphant in California, in September 1941, was one such moment.

Australian physicist Sir Mark Oliphant.

Oliphant pictured during his September 1941 trip to Berkeley, where he met with Oppenheimer and Lawrence. (Donald Cooksey/Public domain)

Fremantle-based historical researcher and geoscientist Darren Holden, who has investigated the encounter in detail, notes that it was the Australian, not the American, who instigated it.

"Oliphant's meeting brought in Oppenheimer who had, up until then, been part of the chorus line of theoretical physicists and had certainly not been involved in any applied bomb research," Dr Holden wrote in a research paper on the subject.

"Oliphant shifted Oppenheimer from the shadows of theory and into the light of practicality, and thus began his passage towards his place in history."

A photographic portrait of a man wearing glasses.

Darren Holden has investigated the meeting between Oliphant and Oppenheimer, and its role in the Manhattan Project. (Supplied)

By 1939, scientists were aware not only of the latent power of the atom, but of the possibility of a bomb: after the discovery of fission by chemists in Germany and physicists in Denmark and Sweden, a letter signed by Einstein was sent to US President Franklin Roosevelt, warning of unprecedented and "extremely powerful" weapons.

The following year, another major breakthrough occurred when two of Oliphant's colleagues at the University of Birmingham — Jewish refugees Otto Frisch and Rudolf Peierls — demonstrated the feasibility of a "super-bomb" using the isotope uranium-235, rather than the more plentiful but far less fissile uranium-238.

"They came up with the uranium-235 critical mass equations, that show that a nuclear bomb with uranium would be able to be constructed and able to be transported by aircraft," Dr Holden said.

Armed with this knowledge, Oliphant left Britain for America in 1941.

Amid concerns that Nazi Germany could develop such a weapon, and worried that nuclear research was languishing in the UK, he took matters into his own hands.

"He decided that he needed to act, and – I believe – without authority, in order to convince the Americans. He needed an ally," Dr Holden said.

That ally was experimental physicist Ernest Lawrence, whom Oliphant met in Berkeley with the intention of involving America — then still a neutral nation — in Allied efforts to produce a bomb.

A black and white image of a young man smoking a cigarette.

J. Robert Oppenheimer several years after the Berkeley meeting with Oliphant. (Wikimedia: Ed Westcott/US Government)

It was Lawrence who sought the assistance of Oppenheimer, by asking him to "check the numbers" in the Frisch-Peierls paper.

"It was essentially at that point that Oppenheimer was brought in," Dr Holden said.

"It's from that moment we can really see a reinvigoration [in nuclear research], and the birth of what became the Manhattan Project."

Remorse or pride?

The physicists who built the first nuclear weapons became, in the public imagination, demigods who had unlocked a fundamental secret of the universe to end a world war.

"Oppenheimer became a pin-up boy of American science after the war," Dr Holden said.

A white man with light brown hair and wearing a grey 40s suit, stands in a windswept and gloomy desert landscape.

In books and films, there has been a tendency to depict Oppenheimer as a tortured soul. (Supplied: Universal)

But literary voices – especially those who specialised in the depiction of dystopias — were among the first to articulate the moral magnitude of what had changed.

"The nuclear scientist will prepare the bed on which [humankind] must lie," Aldous Huxley stated in a 1946 foreword to Brave New World.

George Orwell was more mordant. In a post-war essay, the future author of Nineteen Eighty-Four offered words of caution about where science untempered by moral considerations might lead:

"A mere training in one or more of the exact sciences … is no guarantee of a humane or sceptical outlook. The physicists of half a dozen great nations, all feverishly and secretly working away at the atomic bomb, are a demonstration of this."

A popular theory persists that the physicists who devised and developed the bomb were racked with guilt.

This scientist found himself at the eye of a nuclear storm

Photo shows An image combining a portrait of CSIRO scientist Hedley Marston with a photo of a nuclear test.An image combining a portrait of CSIRO scientist Hedley Marston with a photo of a nuclear test.

Hedley Marston was, in many respects, an establishment man — but when he began studying nuclear fallout from British bomb tests at Maralinga, he became incensed.

But did they really regret their involvement? Was Oppenheimer, as two of his biographers have called him, an "American Prometheus"? And to what extent is the label "Australia's Oppenheimer" a fitting description of Oliphant?

In Oliphant's case, the evidence points in different directions.

Dr Holden notes that Oliphant and Oppenheimer continued to collaborate after the war, but on a cause very different to the one that had occupied them in 1941.

"[They] worked together to try and convince the governments of the world, and the United Nations, to ban atomic weapons for everybody," he said.

Nevertheless, less than 50 years after Hiroshima, the putatively pacifist Oliphant (by then Sir Mark) remained sufficiently pleased with his work on the bomb to write a letter to The Advertiser newspaper in 1986 in which he championed the British contributions to the Manhattan Project.

In an incisive evaluation of Oliphant's legacy, Dr Holden has argued that the physicist was "naive to assume" that wartime scientific gains "would be utilised in peacetime only for the greater good", and that Oliphant "remained proud rather than remorseful of his time at the Manhattan Project".

"It is overly simple to consider that it was scientists' remorse — of the part they played in creating atomic weaponry — that drove them to enter the postwar atomic science peace movement," Dr Holden has written.

Oliphant, Oppenheimer and the dozens of other physicists and chemists involved in the construction of the bomb thus remain ambiguous figures in the history of scientific research.

Their proximity to what was one of the most intensive, elaborate, formidable and destructive engineering endeavours ever undertaken perhaps denied them the kind of perspective afforded to non-scientists like Bruce Dawe, whose poem (quoted above) on the shadow of a Japanese child "blasted upon" a surface at Hiroshima ends with these words:

"In your blackened absence, this stencilled outline on the wall haunts us all with its unending play."

https://www.abc.net.au/news/2023-08-05/j-robert-oppenheimer-mark-oliphant-and-the-atomic-bomb/102577024

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De: BARILOCHENSE6999 Enviado: 09/02/2025 15:01

Mark Oliphant

 
 
 
Plantilla:Infotaula personaSir Mark Oliphant
ACKBEFRS, FAA
Imatge
Mark Oliphant (1939)
Biografia
Naixement 8 octubre 1901 Modifica el valor a Wikidata
Adelaida (Austràlia) Modifica el valor a Wikidata
Mort 14 juliol 2000 Modifica el valor a Wikidata (98 anys)
Canberra (Austràlia) Modifica el valor a Wikidata
 
27è Governador d'Austràlia Meridional
1r desembre 1971 – 30 novembre 1976
← James Harrison – Douglas Nicholls → Modifica el valor a Wikidata
Dades personals
Residència Government House (en) Tradueix
Hughes (en) Tradueix Modifica el valor a Wikidata
Nacionalitat Australià
Formació
Tesi acadèmica The Neutralization of Positive Ions at Metal Surfaces, and the Emission of Secondary Electrons (1929)
Director de tesi Ernest Rutherford
Es coneix per
Activitat
Camp de treball Física Modifica el valor a Wikidata
Ocupació físicgovernadorfísic nuclear Modifica el valor a Wikidata
Organització
Partit Demòcrates Australians (1977–)
Partit Australià (–1977) Modifica el valor a Wikidata
Membre de Royal Society
Acadèmia Australiana de Ciències Modifica el valor a Wikidata
Influències Ernest Rutherford Modifica el valor a Wikidata
Participà en
 
1939 Projecte Manhattan Modifica el valor a Wikidata
Obra
Estudiant doctoral Ernest William Titterton
Localització dels arxius
Premis


Find a Grave: 37302155 Modifica el valor a Wikidata

Sir Marcus "Mark" Laurence Elwin Oliphant (1901 – 2000) va ser un metge australià que va tenir un paper important en els experiments de la fusió nuclear i també en les armes nuclears.

Nascut a Kent Town (Austràlia), l'any 1927 es traslladà a Anglaterra on va estudiar sota Sir Ernest Rutherford a la Universitat de Cambridge al Laboratori Cavendish. Allà, usant un accelerador de partícules, va descobrir l'heli-3 i el triti.

Arran la Segona Guerra Mundial va estar involucrat en la invenció del radar. Oliphant també formà part del MAUD Committee el qual va informar el juliol de 1941 que es podria produir una bomba atòmica ja a principis de 1943.

Després de la guera, Oliphant tornà a Austràlia com el primer Director de la Research School of Physical Sciences and Engineering a la nova universitat Australian National University. Es va retirar l'any 1976, però va ser nomenat governador d'Austràlia del Sud pel Primer Ministre Don Dunstan. Va esdevenir partidari de l'eutanàsia voluntària

Bibliografia

[modifica]
  • Oliphant, Mark. The Atomic age. Londres: G. Allen and Unwin, 1949. OCLC 880015. 
  • Oliphant, Mark. Science and the Future. Bedford Park, South Australia: Flinders University Science Association, 1970. OCLC 37096592. 
  • Oliphant, Mark. Rutherford: Recollections of the Cambridge Days. Amsterdam: Elsevier Pub. Co., 1972. ISBN 978-0-444-40968-3OCLC 379045.

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De: BARILOCHENSE6999 Enviado: 09/02/2025 15:20

Sir Mark OliphantPrint Page Print this page

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Photographs supplied by Stephen Warren

The Mark Oliphant Conservation Park commemorates the commitment to conservation by scientist and former Governor of South Australia, Sir Mark Oliphant.  He was the first South Australian born Governor. The park was formerly the Lofty Recreation Park. 

Sir Marcus 'Mark' Laurence Elwin Oliphant, AC, KBE, FRS (8 October 1901 – 14 July 2000) was an Australian physicist and humanitarian who played a fundamental role in the first experimental demonstration of nuclear fusion and the development of the atomic bomb.

During retirement he was appointed Governor of South Australia by Premier Don Dunstan a position he held from 1971 to 1976.   In 1977 he assisted in the founding of the Australian Democrats political party.

Location

https://monumentaustralia.org.au/themes/people/government---state/display/118675-sir-mark-oliphant

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Saint of the day: St. Lawrence


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