A Warsaw childhood
Józef Rotblat was born on 4 November 1908 in Warsaw, then part of the Russian-ruled Kingdom of Poland, into a Polish-Jewish family. He was one of seven children, two of whom died in infancy. His father, Zygmunt Rotblat, had built up a nationwide horse-drawn carriage business, and Józef’s early years were comfortable, but the First World War ruined the family: borders closed, the horses were requisitioned, and the Rotblats fell into poverty.
His parents could not afford a gymnasium, so he received his secondary education in a cheder, a traditional Jewish school taught by a local rabbi, and then at a technical school, where he trained as an electrician. Though raised in a religious home, he had begun to doubt the existence of God by the age of ten and later described himself as an agnostic. He worked as an electrician in Warsaw while dreaming of becoming a physicist.
Becoming a physicist
In 1929 Rotblat sat the entrance examinations of the Free University of Poland. He passed physics easily but struggled with an essay on a subject he knew nothing about; the physicist Ludwik Wertenstein, who had studied under Marie Curie in Paris and Ernest Rutherford in Cambridge, interviewed him and offered him a place. He earned a master’s degree in 1932 and a doctorate in physics from the University of Warsaw in 1938, while working in Wertenstein’s Radiological Laboratory. Around this time he married Tola Gryn, a literature student he had met at a summer camp in 1930.
Before the Second World War Rotblat carried out experiments showing that neutrons are emitted when uranium nuclei split. In early 1939 he realised that a chain of fissions occurring fast enough could release enormous energy in less than a microsecond: in other words, an explosion. That year he went to the University of Liverpool to work with James Chadwick, the discoverer of the neutron, intending to build a cyclotron, a particle accelerator, back in Warsaw.
War and a terrible loss
In August 1939 Rotblat returned to Warsaw to bring Tola to England, but she was recovering from an operation and stayed behind, expecting to follow within days. The German invasion of Poland on 1 September trapped her. For months he tried desperately to get her out through Denmark, with the help of Niels Bohr, then through Belgium and finally Italy, but each route closed as the war spread. He never saw her again. She was murdered in the Holocaust at Belzec. The loss affected him for the rest of his life, and he never remarried.
Much of the rest of his family survived. His sister Ewa, with false Catholic identity papers obtained by her husband, smuggled relatives out of the Warsaw Ghetto, and his mother, brother and others hid in a concealed bunker near Otwock. After the war Rotblat accepted British citizenship partly so that he could help them emigrate to England, where they lived with him for a time.
The scientist who walked away
Rotblat had realised early that fission could make a bomb, and he joined Chadwick in Britain’s atomic project for one reason: he feared Hitler would build one first, and believed the only defence was for Britain to be able to retaliate. In February 1944 he went to Los Alamos as part of the British mission to the Manhattan Project. Unusually, he declined to become a British subject or American citizen, and the requirement was waived.
By the end of 1944 it had become clear that Germany had abandoned its bomb programme. For Rotblat, the reason for working on the weapon had disappeared, and he asked to leave on grounds of conscience. He was the only scientist to quit the Manhattan Project for moral reasons. He later recalled being shocked when the project’s director, General Leslie Groves, said at a dinner that the real purpose of the bomb was to subdue the Soviet Union, though historians have debated the details of that account. When the bombs fell on Hiroshima and Nagasaki in August 1945, he felt betrayed.
Physics for medicine and the truth about fallout
Determined that his research should serve only peaceful ends, Rotblat turned to medicine. From 1950 to 1976 he was professor of physics at St Bartholomew’s Hospital Medical College in London and the hospital’s chief physicist, studying the effects of radiation on living organisms and the medical uses of nuclear physics. He edited the journal Physics in Medicine and Biology from 1960 to 1972, served as president of the Hospital Physicists’ Association and the British Institute of Radiology, and sat on the World Health Organization’s Advisory Committee on Medical Research. He also organised the Atom Train, a travelling exhibition from 1947 that taught the public about both the peaceful and military uses of nuclear energy.
His work on radiation led him to fallout. In 1955 he analysed the 1954 American Castle Bravo hydrogen-bomb test at Bikini Atoll, using data that Japanese scientists had gathered after a fishing boat, the Lucky Dragon, was showered with radioactive ash. He deduced that the bomb had three stages and that its final fission stage multiplied the radioactivity released many times over, far more than officially stated. His findings were taken up by the press and fed the public debate that led to the Partial Nuclear Test Ban Treaty of 1963, which ended atmospheric tests by its signatories.
A physicist’s practical gifts
Alongside his campaigning, Rotblat remained a productive scientist and a skilled organiser of research. After the war he chaired the photographic emulsion panel of Britain’s Nuclear Physics Committee, which developed the sensitive emulsions that made possible the discovery of the pi meson, and its cyclotron panel, which planned and supervised the building of cyclotrons for Harwell and Liverpool. The Royal Society noted his observations on the angular distribution of protons from nuclear reactions, which became an important tool for determining the spin and parity of nuclear energy levels.
He co-founded the Atomic Scientists Association in 1946 and the UK Panel on Gamma and Electron Irradiation in 1966, and in 1977–1978 he helped set up a school of biophysics at the University of Penang in Malaysia. He helped establish a chair of peace studies at the University of Bradford, advised the United Nations for the 1986 International Year of Peace, and served as a programme adviser to Threads (1984), the BAFTA-winning television drama that showed British audiences what a nuclear war would mean for ordinary people.
Pugwash: scientists talking across the Iron Curtain
In 1955 Rotblat was the youngest signatory of the Russell–Einstein Manifesto, in which eleven leading scientists warned that nuclear war could end humanity and urged governments to settle disputes peacefully; he chaired the press conference that launched it. The manifesto led to the first Pugwash Conference on Science and World Affairs, held in 1957 in the village of Pugwash, Nova Scotia, which Rotblat organised with Bertrand Russell. He served as its secretary-general until 1973 and later as its president.
Pugwash brought together scientists from East and West at the height of the Cold War, when official contacts were frozen. Western governments at first suspected it of being a communist front, but it earned respect, and its informal channels are credited with laying groundwork for the Partial Test Ban Treaty of 1963, the Nuclear Non-Proliferation Treaty of 1968, the Anti-Ballistic Missile Treaty of 1972, the Biological Weapons Convention of 1972 and the Chemical Weapons Convention of 1993. Rotblat also co-founded the Campaign for Nuclear Disarmament in 1958 and the Stockholm International Peace Research Institute, and was largely responsible for the World Health Organization’s reports of 1984 and 1987 on the effects of nuclear war on health.
Nobel Prize and a scientist’s oath
In 1995, fifty years after Hiroshima and Nagasaki, the Norwegian Nobel Committee awarded the Nobel Peace Prize jointly to Rotblat and the Pugwash Conferences “for their efforts to diminish the part played by nuclear arms in international politics and, in the longer run, to eliminate such arms.” He was eighty-six. In his Nobel lecture he described how science, which he had always linked with benefit to people, had become identified with death and destruction, and he called on scientists to take moral responsibility for their work. He ended with the words of the Russell–Einstein Manifesto: “Above all, remember your humanity.”
Rotblat argued that scientists should have their own code of conduct, a kind of Hippocratic Oath for science. He wrote more than 300 publications, including 20 books, on nuclear and medical physics, radiation hazards, arms control and the social responsibility of scientists. He was made a CBE in 1965, a Fellow of the Royal Society in 1995 and a Knight Commander of the Order of St Michael and St George in 1998 for services to international understanding.
Last years and legacy
Rotblat campaigned against nuclear weapons until the end of his life, arguing that after the Cold War no rationale for them remained. He suffered a stroke in 2004 and died of septicaemia at the Royal Free Hospital in London on 31 August 2005, aged ninety-six. A plaque outside the offices of British Pugwash in London commemorates him.
His legacy is both an example and a set of institutions. He showed that a scientist can say no, even to a war effort, when conscience demands it. His fallout research helped end atmospheric nuclear testing, which had spread radioactive contamination around the globe. And the Pugwash network he built kept scientists talking across hostile borders for decades, helping to create the treaties that still limit nuclear, chemical and biological weapons today.
Sources & further reading
Joseph Rotblat, Biographical, NobelPrize.org · Joseph Rotblat, Nobel Lecture: Remember Your Humanity, NobelPrize.org · Joseph Rotblat, Jewish Virtual Library · Joseph Rotblat, Wikipedia · Researched from the sources above and checked against them. Spotted an error? Tell us.
A life of tikkun olam. This is part of tikkun olam, the Jewish idea of repairing the world, and every one of us can add to it.