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).
