Salam, Abdus

views updated May 17 2018

Abdus Salam

Pakistani Physicist Abdus Salam (1926-1996) devoted a great deal of research time in the 1950s and 1960s to the study of the relationships between two of the four forces scientists believed governed nature: the electromagnetic force and the weak force. In 1968 he published a paper containing his theory that these two forces may actually be two manifestations of the same fundamental force, the electroweak force. By 1973 additional research had substantiated this theory, and in 1979 Salam was awarded the Nobel Prize for his work. In addition, he helped to found the International Center for Theoretical Physics in Trieste, Italy.

Born on January 29, 1926, in Santokdas, in British India's Western Punjab (now Pakistan), Salam grew up in Jhang, a small, rural town. He was the son of Muhammad and Hajira Hussain, and his father worked for the local department of education. Salam showed an early talent for mathematics, and when he was 16 years old he enrolled at the Government College at Punjab University in Lahore, Pakistan, after earning the highest marks ever recorded at his school. Salam published his first paper, which considered an algebraic problem by noted Indian mathematician Srinivasa Ramanujan, when he was age 17, and in 1946 received his master's degree in mathematics. He was then awarded a scholarship to travel to England to attend St. John's College, Cambridge. At Cambridge Salam worked with theoretical physicist Nicholas Kemmer. At the time, Paul Matthews, another student of Kemmer's, was working on his Ph.D. in extending renormalization theory from quantum electrodynamics to meson theories. Salam joined Matthews and focused his attention on one of the problems related to this work. He quickly succeeded in solving it, thus establishing his reputation as an outstanding talent in the field. Salam then joined Matthews for a year of study at Princeton University. In 1949, Salam received a bachelor's degree in mathematics and physics, with highest honors.

Return to Pakistan Brought
Disappointment

For the next two years, Salam pursued graduate study at Cambridge, but he eventually felt obligated to return to his home country. In Pakistan he took a position as professor of mathematics at the Government College of Lahore, and he also became head of the department of mathematics at Punjab University. However, Salam was disappointed because these positions did not allow him to conduct research. As he told Nina Hall in New Scientist, "I learnt that I was the only practicing theoretical physicist in the entire nation. No one cared whether I did any research. Worse, I was expected to look after the college soccer team as my major duty besides teaching undergraduates." In addition to his difficulty in finding a position where he could do research, Salam experienced increasing prejudice due to his membership within the Ahmadiyya sect of Islam. Many Pakistanis were members of a different branch of Islam, which viewed the Ahmadiyya followers as heretics.

Discouraged by these setbacks, Salam returned to Cambridge, where he earned his Ph.D. in theoretical physics in 1952. For the next two years he taught mathematics at Cambridge as a lecturer and fellow. In 1957 he accepted an appointment as professor of theoretical physics at the Imperial College of Science and Technology in London, England. Salam, who retained his position at the Imperial College, in 1959, at age 33, became the youngest member of the Royal Society, based in London.

Found Unifying Theory

In the mid-1950s Salam began considering a fundamental question of modern physics: whether the various forces that govern everything in nature might actually be manifestations of the same basic force. At the time, scientists knew of four fundamental forces: gravitational force, electromagnetic force, strong force, and weak force. They also believed that if these forces were unified, this unification would not be visible or apparent except at levels of energy vastly greater than the ones humans encounter in the everyday world. These levels of energy exist in cosmic radiation, as well as in the most powerful particle accelerators ever built, so it is difficult for scientists to truly prove if in fact the fundamental forces are unified; most efforts to do so are theoretical exercises that involve complex mathematical formulas and calculations. However, by the 1960s Salam and fellow physicists Steven Weinberg and Sheldon Glashow each independently came up with a mathematical theory that unified two of the four basic forces. All men came up with the same theory, although they started from different beginning points and followed different pathways to their results.

The new theory predicted the existence of new, previously unknown, weak "neutral currents." In 1973 these currents were observed in experiments at the European Centre for Nuclear Research (CERN) in Geneva, Switzerland, and these experiments were later replicated at the Fermi National Accelerator Laboratory in Batavia, Illinois. The three physicists also predicted the existence of force-carrying particles, called W+, W-, and Z0 bosons. For their work, Salam, Weinberg, and Glashow were jointly awarded the 1979 Nobel Prize in Physics; Salam arrived at the ceremony wearing the traditional Pakistani dress of jeweled turban, baggy pants, scimitar, and curly toed shoes. In 1983 the existence of the force-carrying particles they had predicted was confirmed in experiments at CERN.

Assisted Other Physicists

In addition to his interest in purely theoretical physics, Salam had a lifelong interest in promoting the careers and status of theoretical physicists in developing nations, perhaps because of his own experiences, which had forced him to leave his home in Pakistan. He believed that theoretical physicists in developing countries needed support, encouragement, and instruction, and he decided that a training center should be established to provide this help. In 1964, with the help of the International Atomic Energy Agency, the Italian government, and the city of Trieste, Salam established the International Center for Theoretical Physics (ICTP) in Trieste, Italy; the center invites theoretical physicists from all over the world to lecture and teach students from developing nations. Hall noted that the Center is also a place for theoretical physicists from developing countries to meet and find camaraderie and common ground, "a sort of lonely scientist's club for Brazilians, Nigerians, Sri Lankans, or whoever feels the isolation resulting from lack of resources in their own country." Salam used his share of the Nobel Prize money to support the ICTP and never spent any of it on himself or his family.

Salam was director of the ICTP from its founding until his retirement in 1994. In addition, he served as a member of Pakistan's Atomic Energy Commission from 1958 to 1974 and as a member of Pakistan's Science Council from 1963 to 1978. He was chief scientific advisor to the president of Pakistan from 1961 to 1974, and was chair of Pakistan's Space and Upper Atmosphere Committee from 1962 to 1963. He also served various international groups, From 1964 to 1972 he was a member and later chair of the U.N. Advisory Committee on Science and Technology; served as vice president of the International Union of Pure and Applied Physics from 1972 to 1978, and was a member of the Stockholm International Peace Research Institute from 1970 until his retirement. Salam received over two dozen honorary degrees and many awards, including the Atoms for Peace Award (1968), the Royal Medal of the Royal Society (1978), the John Torrence Tate Medal of the American Institute of Physics (1978), and the Lomonosov Gold Medal of the USSR Academy of Sciences (1983).

A student of Salam's, M. J. Duff, spoke about Salam at a 1996 physics workshop and posted these remarks on the University of Michigan Center for Theoretical Physics Web site "Being a student of someone so bursting with new ideas as Salam was something of a mixed blessing: he would allocate a research problem and then disappear on his travels for weeks at a time.… On his return he would ask what you were working on. When you began to explain your meager progress he would usually say, 'No, no, no. That's all old hat. What you should be working on is this,' and he would then allocate a completely new problem." Duff noted that after experiencing this several times, Salam's students "began to wise up and would avoid him until we had achieved something positive."

Personal Life

Even while living in England, Salam continued to fight prejudice against his religious group in Pakistan. In 1974 Pakistani president Zulfikar Ali Bhutto declared that the Ahmadiyya sect was not Muslim. In protest, and to show his solidarity with Islam, Salam grew a beard and adopted the name Muhammad. He also frequently spoke throughout developing countries, but most notably in Islamic countries, and often noted that for several centuries the Arab and Muslim world had been in the forefront of science, far ahead of Europe and other parts of the world. He encouraged the founding of other centers similar to the ICTP, and became the first president of the Third World Academy of Sciences.

Salam was married twice, according to Islamic law, which allows men to marry up to four wives. He had six children: one son and three daughters by his first marriage, and a son and daughter by his second. As he grew older, he suffered from a degenerative neurological disease, progressive supranuclear palsy. This illness made it difficult for him to talk, and to walk, and he began using a wheelchair, while continuing to work as much as he could. Although he was ill, he still made remarkable contributions to research. In 1994 Salam retired from his post as director of the ICTP, and he died at his home in Oxford, England, on November 21, 1996, after a long illness. He was buried in the Ahmadia burial ground in Rabwah, Pakistan. In his honor, the ICTP was renamed the Abdus Salam ICTP. It has continued to help scientists from developing countries conduct research and pursue their careers.

After Salam's death, his reputation as a scientist led a publisher of fine art, Illuminocity, to make him the figure-head in a campaign to promote a positive view of Islam through the construction of a museum devoted to the history of Islamic sciences. The museum, exhibiting a collection of artwork titled "Heroes of Science," housed a painting of Salam by artist Ro Kim, who also painted portraits of President Bill Clinton and the president of Korea.

In a tribute to Salam in the Australian, a writer noted, "Salam was a striking man. Any young scientist who worked closely with him invariably found it to be an exhilarating and character-forming experience. In addition to his intellectual gifts, he had a genuine sense of humor, including that rarest of qualities of being able to laugh at himself. A warm twinkle would often accompany his more unorthodox suggestions as to how exactly the foundation of physics should be revolutionized."

Books

Building Blocks of Matter: A Supplement to the Macmillan Encyclopedia of Physics, edited by John S. Rigden, Macmillan Reference USA, 2003.

Notable Scientists: From 1800 to the Present, Gale, 2001.

World of Scientific Discovery, second edition, Gale, 1999.

Periodicals

Australian, December 2, 1996.

New Scientist, October 18, 1979; January 27, 1990.

Online

"Abdus Salam: Biography," Nobel e-Museum,http://www.nobel.se/physics/laureates/1979/salam-bio.html (January 5, 2004).

"Professor Abdus Salam," ICTP Web site,http://www.ictp.Trieste.it/ProfSalam/index.html (January 5, 2004).

"A Tribute to Abdus Salam," University of Michigan Center for Theoretical Physics Web site,http://feynman.physics.lsa.umich.edu/~mduff/talks/ (January 5, 2004).

Salam, Abdus

views updated May 14 2018

SALAM, ABDUS

Abdus Salam (he added "Muhammad" much later) was born in Pakistan but spent most of his life as a leading theoretical physicist in England and Italy, making outstanding contributions to quantum field theory and particle symmetries.

Education

Salam was born January 29, 1926, at Santokdas in Western Punjab, which was then part of British India and is now part of Pakistan. He spent his childhood in the small town of Jhang, where his father was a teacher. At fourteen, he won a scholarship to Government College, Lahore, with the highest marks ever recorded. His first paper, on an algebraic problem of Srinivasa Ramanujan, was published when he was just seventeen.

In 1946, the Punjab Government awarded Salam a scholarship to Cambridge, where he studied mathematics and physics, and was then taken on as a research student in theoretical physics by Nicholas Kemmer. Another student of Kemmer's, Paul Matthews, was then finishing his Ph.D., working on extending renormalization theory from quantum electrodynamics to meson theories. Salam began work on one of the outstanding problems and very rapidly succeeded in showing that the process of removal of infinities works also in the case of so-called overlapping divergences, work that immediately established his reputation. He then went with Matthews to spend a very productive year in Princeton.

Lahore, Cambridge, and Imperial College

In 1952, Salam returned briefly to Pakistan as Professor of Mathematics at Punjab University and Government College, but he found it impossible to continue his research and encountered increasing prejudice against the Ahmadiyya sect to which he belonged; they were regarded by many orthodox Muslims as heretical. He returned to Cambridge as a Lecturer and Fellow of St. John's in 1954. Then in 1956 he was invited to Imperial College, London, where he and Matthews set up a very lively theoretical physics group. He remained a professor there until his retirement. In 1959, he was elected as the youngest member of the Royal Society at the age of thirty-three.

Founding of the ICTP

Salam greatly regretted having to leave his native country to pursue his chosen career and determined to do what he could to help others avoid this dilemma. As Pakistan's delegate, he persuaded the International Atomic Energy Agency to set up an

International Centre for Theoretical Physics (ICTP) in Trieste, with support from the Italian Government and the City of Trieste. Salam became its founding Director, and so remained until his retirement in 1994, dividing his time between London and Trieste. The ICTP was later cosponsored by UNESCO and has grown to a very large and internationally respected establishment, which was renamed the Abdus Salam ICTP. Through its associateship program, it has helped many physicists from developing countries to maintain contacts with front-line research.

Research

Much of Salam's research was concerned with symmetries in quantum field theories, beginning with hadronic symmetries and the chiral symmetry implied by vanishing neutrino mass. Unification was a major theme. With John Ward in the sixties he wrote a series of papers struggling with the problems of constructing a unified gauge theory of weak and electromagnetic interactions. The culmination was the proposal of the electroweak theory, independently proposed by Steven Weinberg. For this, Salam won the 1979 Nobel Prize in Physics, together with Weinberg and Sheldon Glashow.

Later, Salam worked on the possibility of extending the unified theory to include strong interactions and gravity. With Jogesh Pati, he was one of the first to propose a grand unified theory predicting instability of the proton. He made important contributions to the ideas of supersymmetry; with John Strathdee, he developed the superfield formalism and was one of the early proponents of supergravity.

International Development

Salam was a passionate advocate of the importance to developing countries of building a scientific base. From 1961 he was scientific advisor to President Ayub Khan, helping to set up research institutes on subjects from nuclear power to wheat and rice. But he was frustrated by his inability to persuade the government to devote to science the resources he thought essential. In 1974, he was outraged when the Government of Zulfikar Ali Bhutto declared the Ahmadiyya sect to be non-Muslim. To emphasize his Muslim credentials, he grew a beard and later adopted the name Muhammad.

After winning the Nobel Prize, Salam was much in demand as a speaker throughout the developing world and particularly in Islamic countries. Tirelessly he used these occasions to argue the case for science; his dream was to revive the spirit of free inquiry that for several centuries once made the Arab world the standard-bearer for science. He argued strongly for the establishment of centers similar to the ICTP. He also took the lead in establishing the Third World Academy of Sciences and became its first President.

Honors

Salam was a member of twenty-four academies, including the Royal Society, the U.S. National Academy of Sciences, and the Soviet Academy. Among many prizes, in additional to the Nobel, he won the Atoms for Peace Award in 1968, the first Edinburgh Medal and Prize (1988), the Catalunya International Prize (1990), and the Royal Society's premier award, the Copley Medal (1990). He received forty-five honorary doctorates from twenty-eight different countries. In 1989 he was awarded an honorary knight-hood (K.B.E.).

Final Years

Salam married twice and had six children. His final years were blighted by a degenerative neurological complaint, progressive supranuclear palsy (PSP). He found it increasingly difficult to talk and to move about, and he became confined to a wheelchair, but he bore his affliction with remarkable stoicism. So long as he possibly could, he continued to work. He still made innovative contributions to research on the origin of biological chirality and on models of high-temperature superconductivity. In 1994 he had to give up his post as Director of the ICTP, becoming instead its first President. He died at his home in Oxford on November 21, 1996, and was buried at Rabwah in Pakistan.

See also:Conservation Laws; Gauge Theory; Quantum Chromodynamics; Quantum Field Theory; Renormalization; Symmetry Principles

Bibliography

Hamende, A. M., ed. From a Vision to a System: the International Centre for Theoretical Physics of Trieste (1964–1994) (Fondazione Internazionale Trieste per il Progresso e la Libert à delle Scienze, Trieste, 1996).

Kibble, T. W. B. "Muhammad Abdus Salam, K.B.E." Biographical Memoirs of Fellows of the Royal Society 44 , 385–401(1998).

Lai, C. H., and Kidwai, A., eds. Ideals and Realities, selected essays of Abdus Salam, 3rd ed. (World Scientific, Singapore,1989).

Singh, J. Abdus Salam, a Biography (Penguin Books, New Delhi, India,1992).

T. W. B. Kibble

Salam, Abdus

views updated May 29 2018

Salam, Abdus (1926–96) Pakistani physicist who proposed (1967) a theory that unifies the electromagnetic and weak nuclear forces (see fundamental forces) within the nucleus of an atom. Salam and Steven Weinberg worked independently on the theory (now known as the Weinberg-Salam theory). After it was proved experimentally, the pair shared the 1979 Nobel Prize in physics with Sheldon Glashow, who independently came to similar conclusions.

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