Salam, Muhammad Abdus (Abdussalam)

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SALAM, MUHAMMAD ABDUS (ABDUSSALAM)

(b. Santokh Das, Punjab, India/Pakistan, 29 January 1926; d. Oxford, United Kingdom, 21 November 1996)

theoretical physics, high-energy physics, and particle physics, science in developing countries.

Abdussalam shared the 1979 Nobel Prize in Physics with Sheldon Glashow and Steven Weinberg for the unification of weak and electromagnetic interactions. Salam, the first professor of theoretical physics at London’s Imperial College, directed the International Centre for Theoretical Physics in Trieste, Italy, for nearly thirty years.

Early Years and Education Abdussalam, a name that means “servant of God, who is Peace,” was born in the undivided province of Punjab, then part of British India (after partition in 1947, his birthplace of Santokh Das became part of Pakistan). He came from a devoted Muslim family that cultivated learning and education. His grandfather, who practiced traditional herbal medicine, was an officer in the Department of Government Revenues. Graduating in 1899 from Islamiya College in Lahore, Salam’s uncle later worked in the Punjab government’s Education Department. His father was a school-teacher but later became head clerk of the office of the District Inspector of Schools.

The most important influence in Salam’s early years was his father, Chaudhri Muhammad Hussain. He trained young Salam through individual coaching and mentoring to become a civil servant. Chaudhri Muhammad, a devout Muslim, made his faith and heritage an integral part of his son’s education. Salam’s family belonged to an Islamic movement called the Ahmadiyya-Jammat (Ahmadiyya Movement, or Ahmadiyya Society). The tenets of this doctrine are very controversial for mainstream Islam. According to the orthodoxy there is no successor to Muhammad (although it accepts Jesus as a prophet). Ahmad claimed that, according to his interpretation of the Qur’an he could “prove” that Jesus Christ had died a natural death. Then, in 1889, he proclaimed himself the Promised Messiah (Mahdi). The Islamic authorities accused Ahmad of heresy and apostasy. It established its headquarters in Qadiyan, near a small village called Faizullah Chak where Salam’s mother had been born. From there, it expanded through groups of missionaries to the West African coast; one of Salam’s uncles belonged to one of them. Although the movement was tolerated, since the mid-twentieth century it has been fiercely persecuted in Pakistan. After the Ahmadiyya community was officially declared illegal in Pakistan, in 1974, Salam added also “Muhammad” as a sign of his faith and as a political act in support of his movement. Salam did not see any contradiction between religion and science. Citing from the Qur’an, Salam suggested that discovering the fundamental symmetries of the nature of all forces resided at the core Islamic doctrine.

Salam was an outstanding student. In high school, he graduated first in the district, with his marks setting a new record in the Province and, two years later, he placed first once again in mathematics and in English at Government College, Lahore. His first experience in politics started when he was elected president of the College Students Union. In 1946, with a civil service career still in mind, he won a scholarship awarded by a British program aimed at training a small number of Indians at a postgraduate level. Salam was admitted at St. John’s College, Cambridge, to read mathematics. In 1948 Salam received a first in the Mathematics Tripos, completing the required cycle in two years instead of three. Then, under the influence of his mentor, mathematician (soon-to-be renowned astrophysicist and cosmologist) Fred Hoyle, and inspired by Paul Dirac’s lectures, Salam decided to pursue a career in theoretical physics. Indeed, in many ways, Dirac became Salam’s icon of a theoretical physicist, although their epistemological approaches to theoretical physics (and particularly to the normalization program in quantum field theory) were markedly different. In 1949 Salam was awarded a degree from Cambridge University with a double first in mathematics (Wrangler) and physics. That same he underwent an arranged marriage. Much later, in

the 1980s, he would marry again, this time on his own; his second wife was an Oxford professor.

Cambridge extended his fellowship, and Salam undertook a PhD in physics. Salam was chosen to do experimental physics, as were the majority of the students in Cambridge who had a first-class degree in physics. However, after a few months, he transferred to Dirac’s department of theoretical physics, where he worked with Nicholas Kemmer and Paul Matthews on the renormalized theory for quantum electrodynamics. Since the 1930s, this branch of quantum field theory applied to electromagnetism had been successful in explaining experimental results, as well as reconceptualizing atomic interactions. Nonetheless, quantum field theory and Dirac’s “hole theory” suffered from the same kind of difficulties: Once applied to higher levels of approximation than the first, measurable (and measured) parameters of the theory appeared via the calculations to be infinite, thus in clear contradiction to the experiments. In the late 1940s Richard Feynman and Julian Schwinger, in conjunction with the earlier studies of Sin-itiro Tomonaga and his co-workers in Japan, invented a method to avoid the infinities, the so-called renormalization. After Freeman Dyson unified these three approaches, Feynman, Schwinger, and Tomonaga were awarded the Nobel Prize in 1965. Although this achievement revived the hope of using quantum field theory effectively to tackle problems relating to the explosion of particles coming from cosmic rays and the new accelerators, the theory could not yet be applied to all varieties. Salam tackled the so-called overlapping divergences problem, a crucial obstacle to know whether meson theory for spin-zero particles was renormalizable. Salam solved the problem and, by doing so, succeeded in applying the new renormalization methods to various meson theories. Abdus Salam became famous practically overnight, and in January 1951 he was invited to join the Institute for Advanced Studies at Princeton. There he continued working on the renormalization program. During this visit, Victor Weisskopf and J. Robert Oppenheimer became very fond of the young Pakistani for his qualities as a physicist and his extraordinary charisma. In autumn 1951 Salam returned to Pakistan. In the meantime, the University of Cambridge awarded him the Smith’s Prize for the most outstanding predoctoral contribution to physics.

Exile and the Missing Nobel Prize On his return to Pakistan, Salam was appointed head of the Mathematics Department at Punjab University, but this experience proved to be traumatic, as was usually the case for most young scientists who, after carrying out research in elite universities, returned to their precarious university systems. In 1952–1953, a violent anti-Ahmadiyya movement arose in the Punjab Province. After many doubts, Salam decided to leave the country after being threatened by rioters. In January 1954 Salam emigrated to Cambridge. He would never again live in Pakistan, although he maintained his Pakistani citizenship throughout his life. That same year, 1954, the Pakistan Academy of Sciences elected him as a Fellow.

Salam had a great sense for identifying crucial problems in high-energy physics. Among other things, he worked on the so-called parity nonconservation problem. Gauge theory, namely using the mathematical concept of group theory to test if an interaction were “symmetrical”—or “invariant”—under certain transformations, was suggested in 1929 by Hermann Weyl. It was revived in 1954 by Chen Ning Yang and Robert L. Mills and, independently, by Salam’s student Ronald Shaw. In the case Salam addressed, the problem was whether or not weak interactions (the nuclear force responsible for radioactivity) were, as was generally accepted, “symmetrical” under transformations such as space inversion, charge conjugation (same charge but with the opposite sign) and time reversal. In particular, if a weak interaction would proceed identically under a space inversion (exchanging right with left), then it would be said to conserve parity. Eventually, the question would be of primary importance because this kind of analysis led to gauge theories as possible means of studying such processes and classifying subatomic particles. In 1956 Yang and Tsung-Dao Lee realized that no previous experiments required the weak force to conserve parity, and that, in fact, parity might not be conserved in those interactions. This revived a two-component neutrino theory discussed by Weyl’s pioneering paper, presented by Wolfgang Pauli in his Handbuch der Physik in 1933. After Yang presented his results, Salam postulated the so-called γ5 symmetry, or “chiral” symmetry. This was an alternative, independent, and elegant explanation of why parity might not be conserved in weak interactions. More importantly Salam found a connection between parity conservation and the fact that neutrinos had zero mass. However, the negative reaction of senior physicists such as Pauli to his paper discouraged him from publishing it. When, in early 1957, Columbia University physicist Chien-Shiung Wu presented her experimental results confirming Yang and Lee’s hypothesis, Salam’s work was still a preprint. In a matter of a few months, parity violation was part of the new physics, but Salam’s contribution appeared much later that same year.

Yang’s and Lee’s Nobel Prize for Physics in 1957 had a great impact on Salam. Several British physicists thought Salam might receive the Nobel Prize for his contribution. Although he did not share the Nobel with his Chinese colleagues, Salam was awarded the Hopkins Prize and the Adams Prize, both from Cambridge University. In 1959 he was elected a Fellow of the Royal Society, becoming the youngest fellow at the time. Yet, for Salam, this episode was also frustrating, and the Nobel Prize became, according to some of his colleagues, “an obsession.” After this incident, although Salam continued to seek advice and support from the scientific elite, he adopted a much more aggressive stance toward publishing. His strategy, followed by his students, was that one should never refrain from publishing. It was the role of the scientific community, he argued, to sort out good ideas from bad. Indeed, Salam was one of the most prolific physicists of his generation, publishing 276 scientific papers.

The 1950s were years of a major expansion of Imperial College, London. In 1953 Nobel laureate Patrick M.

S. Blackett was appointed professor of physics. Imperial was the largest postgraduate school in the United Kingdom. As part of the planned expansion, there was an increasing interest in reinforcing the basic sciences in the college. Hence, in 1957 physicist Hans Bethe, a close friend of Blackett’s who was visiting Cambridge, recommended Abdus Salam for the applied mathematics post. Salam’s chief concern at Imperial was to set up a group strongly tied to the international community. Imperial College, he thought, should also be a training center for a new elite of scientists from Third World countries. First the Mathematics Department, and then the Physics Department, would become exceptionally active, thanks to the presence of Salam. The department received an extraordinary number of visitors. Despite his young age, Salam’s credibility in scientific circles brought some the most eminent physicists to give seminars at Imperial. At the beginning of the 1960–1961 session, Salam became the first professor of theoretical physics at Imperial College, a post he held until his retirement in 1993.

Political Career The consolidation of Salam’s scientific career and his political activities occurred simultaneously. These seemingly disparate activities were actually two increasingly complementary aspects of Salam’s life. As he became part of the international scientific community, his political career encompassed appointments in both international organizations and in Pakistan.

In 1955 and 1958, he was appointed secretary at the Geneva Conference for the Peaceful Uses of Atomic Energy. There he met Swedish physicist Sigvard Eklund. This was the beginning of a long involvement with United Nations politics. Retrospectively, he recalled his first visit to the New York headquarters as “falling in love with all the organization represented—the Family of Man, in all its hues, its diversity, brought together for Peace and Betterment” (1976, pp. 9–15). Salam and Eklund developed a close relationship marked by mutual respect and a common interest in the promotion of science in developing countries. In 1961 Eklund was elected the second director general of the International Atomic Energy Agency (IAEA), an event that was certainly crucial for Salam’s career as a scientific diplomat. Between 1964 and 1975, Salam was a member of the United Nations Advisory Committee of Science and Technology and, from 1970 to 1973, he served as a member of the United Nations Panel and Foundation Committee for the United Nations University.

However, it was in Pakistan that Salam spread his wings as a politician of science. In 1958 the tensions between the eastern and western areas of the country led to a coup d’état orchestrated by the former Chief Martial Law Administrator Ayub Khan—the person who had stopped the anti-Ahmadiyya riots. His regime lasted for eleven years and marked the beginning a technocratic era in which the promotion of science was part of the discourse surrounding the ideology and practice of Pakistan’s economic and cultural development. Salam’s scientific reputation in the West, as well as his youth, humble origins, and determined, but charismatic, personality, made him an ideal symbol of the scientific spirit of modern Pakistan. In 1961 Salam became the chief scientific advisor to the president, a post he held until 1974, when, due to the anti-Ahmadiyya laws decreed by the Pakistani government, he resigned. In collaboration with his friend Cambridge physicist Ishrat H. Usmani, Salam promoted the establishment of the Space and Upper Atmosphere Research Commission (SUPARCO), near Karachi, the creation of the Pakistan Institute of Nuclear Research (Pinstech), and the consolidation of the Pakistan Atomic Energy Commission. After 1958 he became also a member of the following organizations in Pakistan: the Scientific Commission (1959), the National Scientific Council (1963–1975), and the Board of Pakistan Science Foundation (1973–1977). He was advisor to the Education Commission (1959) and chairman of the Pakistan Space and Upper Atmosphere Committee (1961–1964). In 1962 Salam was appointed to the IAEA as a member of the Pakistani delegation.

Meanwhile, a group of scientists, intellectuals and politicians from Trieste (Italy), led by Professor Paolo Budini started a campaign to set up an international center for theoretical physics in that city. The idea had been discussed among a group of physicists, including Salam, during a scientific meeting held in Miramare, near Trieste. As a member of the Pakistani delegation to the IAEA, Salam supported the idea with great resolve. The initiative took four years before the center was formally established under the banner of the IAEA with the financial support of that agency and the Italian government. Salam’s role was crucial in convincing Third World delegations to the IAEA to support the initiative despite the open hostility of both industrialized and communist countries. Budini and the Trieste elite were the main instruments to mobilize Italian diplomats and, consequently, the required financial resources. In 1963 Salam became the first director of the International Centre for Theoretical Physics (ICTP), remaining in office for almost thirty years. In fact, the Budini-Salam alliance determined the double nature of ICTP. The Trieste physicists wanted to reestablish contacts with scientific institutes in central Europe that had been broken off since the end of the Austro-Hungarian Empire, the annexation of Trieste to Italy, and, after 1945, the erection of the Iron Curtain. Salam, politically backed by Eklund, saw the ICTP as an opportunity to promote physics in “developing” countries by establishing a new space for international collaboration with Western physicists.

In a few years, the ICTP became a reference institution for physicists in Africa, Asia, and Latin America. Since 1964, the year the ICTP began operation, it has received more than sixty thousand scientists from 150 countries. This impressive figure is consistent with the ICTP’s estimates that at least one physicist from every physics institute in a developing country has made at least one visit to the ICTP. Moreover, the ICTP was the first United Nations institution entirely devoted to scientific training and research, providing a model for several institutions that now play an important role in developing countries in the fields of science, technology, and development policies. Under Salam’s directorship, the center was devoted to the general goal of scientific exchange between industrialized and developing countries.

Following a model used at CERN (Conseil Européen pour la Recherche Nucléaire, or European Organization for Nuclear Research), western Europe’s premier center for high-energy physics, Salam established the “Associate Membership,” exclusively for the benefit of physicists from and working in developing countries. It gave them the possibility of spending six weeks to three months at the ICTP during a five-year period. Salam conceived the aim of the ICTP’s associate membership program as a possible solution to the “brain drain” problem. He used his considerable scientific prestige to attract reputed scientists from Europe, the Soviet Union, and the United States to give seminars and participate in the courses organized by the ICTP. He set up small groups that carried out research and organized courses on high-energy physics (under his leadership), solid-state physics, plasma physics, nuclear physics, and mathematics. In the 1970s UNESCO (the United Nations Educational, Scientific, and Cultural Organization) joined IAEA to support the center. UNESCO’s instrumentalist view of science forced Salam to include fields beyond theoretical physics. As a result, the ICTP widened its field of action and organized courses on “applicable sciences” such as physics and technology, applied mathematics, and planning models.

The ICTP also became a model for other initiatives in the Third World. In Pakistan, Salam helped to establish the International Schools on Physics and Contemporary Needs in Nathiagali, which sponsored an important annual meeting during the 1970s for scientists in the sub-continent. In the early 1980s, Salam promoted the creation of a twin center of the ICTP in South America. He was instrumental in the establishment of the Centro Internacional de Física in Bogotá, Colombia, which, for several years, received ICTP support to host physics courses attended by scientists from Latin America and the Caribbean. Beginning in 1983 Salam spearheaded the creation of the Third World Academy of Sciences in Trieste, formally launched in 1985 and administered by UNESCO.

Despite ICTP’s intensive activity and visibility among physicists around the world, Salam had to struggle throughout his administration to overcome the fragile situation in which the organization found itself due to its financial instability. The ICTP’s budget was periodically revised in the General Assemblies of IAEA and UNESCO, following proposals led by the United States and the United Kingdom. Thanks to Salam’s political ability and scientific prestige, the center received substantial help from philanthropic foundations such as the Ford Foundation. However, the initial “hard line” adopted by delegations from the industrialized countries concerned about the utility of promoting theoretical physics in poor countries continued for more than thirty years. The ICTP survived thanks both to Salam’s ability to neutralize pressures to withdraw United Nations support and to Budini’s talent in mobilizing Italian resources.

Salam’s Views on Science and Third World Development As a scientist, Salam carried great weight with politicians in Pakistan. As a Muslim born in poor Pakistan, he seemed to be naturally invested with the authority to speak on behalf of the Third World. Indeed, Salam was a “scientific diplomat,” a representative of different communities acting in different social and political settings. After the creation of the ICTP, and especially after being awarded the Nobel Prize, he became one of the most influential participants in the science-for-development discourse. His collected works on science and development, Ideals and Realities, became a reference text for Third World politicians of science in the second half of the twentieth century.

Throughout his life, Salam called for international cooperation in science in general, and theoretical physics in particular, stipulating that such cooperation should take place in an international institution under the banner of the United Nations. Only such an organization could warrant the neutrality in which scientific exchange could occur. It should emulate what had taken place in the eleventh century: the transmission of knowledge from one civilization (Islamic) to another (Christian). The ICTP and other international organizations for science and technology should be the twentieth-century mirrors of Toledo and Gondasipur.

Salam found three main reasons to promote theoretical physics in developing countries. The first reason was that theoretical physics needed no costly apparatus; only, according to him, a good brain, pencil, and paper. This was a stereotype related to the perceived superiority of theory. In contrast to experimentalists, the story goes, theoreticians were able to discover the fundamental laws of nature by purely thinking in the solitude of their offices. The second reason Salam invoked was a metaphysical argument concerning the “fundamentality” of physics. In this view, not only was science above technology in knowledge classification, but, Salam also argued, the question of “fundamentality” of theoretical particle physics had a deeper sense. It involved the transcendental dimension of the search for unity—a central notion in the Islamic tradition. The fourth and last reason to promote theoretical physics was that it had the advantage of being a “glamour subject,” which was attracting the majority of young students interested in science.

The Unification Program and the Nobel Prize Beginning in the late 1950s, Salam’s group at Imperial had become perhaps the most active of the groups working in gauge theories during a period in which quantum field theories had been displaced by another approach, the S-matrix model. While many theorists were looking toward this latter method in the hopes of avoiding the seemingly intractable difficulties that had begun to arise with field-theoretic calculations, Salam believed that a more “fundamental” explanation would have to come from invoking the standard perturbation method for quantum field theory. This conviction, shared by his collaborators at Imperial, was transmitted to his students. In 1964 the group started a research program on gauge theories. The aim of this program was to find the mathematical group of transformations that left “invariant” the laws that rule an interaction: The question was whether or not the interaction depended on certain physical properties of the particles, such as electric charge or other “quantum numbers.”

The group, led by Salam and Paul Matthews, was working on the search for a relativistic version of a symmetry group called SU(6) to classify those particles ruled by the “strong interactions.” Immediately after the establishment of the ICTP, Salam split Imperial’s group between London and Trieste. Bringing part the group to Trieste was a strategy to give the new center scientific visibility, and it worked. Salam and his collaborators Bob Delbourgo and John Strathdee, helped by a constellation of PhD students devoted to difficult, long, and tedious calculations, produced a series of papers exploring relativistic versions of SU(6). Although the results turned out to be incompatible with the available experimental results, as two of Salam’s students showed, the exercise was crucial to familiarize Salam and his group with a set of techniques necessary to continue working in the “unification program” of subatomic interactions. The aim was to find symmetry groups that showed that interactions that seem essentially different are just manifestations of a more general one, such as in the electromagnetic theory, in which Salam’s goal was to unify electromagnetic and weak interactions.

Salam shared the 1979 Nobel Prize for Physics with Glashow and Weinberg for their work on the unification of the weak and electromagnetic interactions. Salam presented his gauge theory for electroweak interactions in a series of seminars at Imperial College in the autumn of 1967. Salam decided not to publish his results in a journal, but in a Nobel symposium the following spring, a widely read publication among physicists, especially the members of the Nobel Committee; the fact that the theory was not “renormalizable” put serious obstacles to empirical verification. Weinberg and Glashow, conversely, did publish their hypotheses. When Gerard t’Hooft proved, in 1971, that gauge theories of the Yang-Mills-Shaw type could be renormalized, the interest of the electroweak unification theories revived. In 1973 the “neutral-currents interactions,” predicted by Glashow, Weinberg, and Salam in their works, were observed. The masses of the intermediate bosons (W+, W and Z0) were not verified until 1983. Salam faced an additional problem: he did not publish his work. However, attendants to Imperial College’s seminar and the ICTP courses spoke and wrote on his behalf. His colleagues and students helped to demonstrate to some members of Nobel Committee, whom Salam invited regularly to visit the ICTP, that the Pakistani physicist had obtained the same conclusion independently from his American colleagues.

Beyond the Nobel Prize In spite of developing progressive supranuclear palsy, a neuronal disease, Salam continued working in science and politics until the end of his life. In the 1970s, Salam and Indian physicist Joghesh Pati struggled to construct the first Great Unified Theory of weak, electromagnetic and strong interactions. Their theory, however, was only partially unified, but it led to further developments in the 1990s. Salam and his lifelong collaborator Strathdee developed a new formalism based on “superspace.” This was a significant innovation for the simplification of calculations concerning supersymmetric theories, particularly for supergravity models. In his final years he redirected his research program, tackling problems in condensed-matter physics and biology.

Since 1975, Salam’s optimism about the willingness of industrialized countries to contribute actively to scientific progress in developing nations had been dimmed by years of frustration. His efforts thus turned more resolutely toward the promotion of South-South collaboration and self-reliance, focusing particularly on problems regarding science in Islamic countries and the establishment of institutions such as the Third World Academy of Science and the International Centre for Science. In the mid-1980s Salam campaigned to become director-general of UNESCO, but being without the support of a national delegation, due to his having broken with the Pakistani regime in 1974, he failed.

Abdus Salam was one of the most influential scientists of the second half of the twentieth century. He was widely respected as one of the most energetic leaders of the unification program. Among the awards received for his contributions to physics are the J. Robert Oppenheimer Memorial Medal and Prize (University of Miami, 1971), the Royal Medal (1978), and the Copley Medal (1990). He was member of twenty-four academies and received forty-five honorary doctorates. As a scientific diplomat, he was perhaps the best-known politician of international science, and he worked diligently to create and promote new spaces of collaboration between scientists to achieve scientific progress in the developing world. He won the Atoms for Peace Award (1968), the Peace Medal (Charles University, Prague, 1981), the First Edinburgh Medal and Prize (1988), and the “Genoa” International Development of Peoples Prize (1988), among others. Abdus Salam died in 1996 and, following his will, was buried in Pakistan, where his name still produces heated debates: after all, he was a member of a marginalized movement in Pakistan, but also the first Muslim and the only Pakistani to win the Nobel Prize.

BIBLIOGRAPHY

Selected Papers of A. Salam (with Commentary), edited by Ahmed Ali, C. Isham, Thomas Kibble, and Riazuddin (Singapore: World Scientific, 1994) contains the most important papers by Abdus Salam.

WORKS BY SALAM

“The Advancement of Science for the Developing Countries.” In The Place of Values in a World of Facts, edited by Arne Tiselius and Sam Nilsson. New York: Wiley Interscience Division and Almqvist & Wiksell, 1969.

“Ideals and Realities.” Lecture given at the University of Stockholm, 23 September 1975. Bulletin of the Atomic Scientists 32 (1976): 9–15.

Ideals and Realities: Selected Essays of Abdus Salam. 3rd ed. Edited by C. H. Lai and Azim Kindwai. Singapore: World Scientific Publishing, 1989. This is a selection of Salam’s papers on science, technology, and international cooperation between industrialized and developing countries.

“Physics and the Excellences of the Life It Brings.” In Pions to Quarks: Particle Physics in the 1950s: Based on a Fermilab Symposium, edited by Laurie Brown, Max Dresden, and Lillian Hoddeson. Cambridge, U.K.: Cambridge University Press, 1989.

With Jacques Vauthier. Abdus Salam un physicien, Prix Nobel de Physique 1979: Entretien avec Jacques Vauthier. Vol. 3, Scientifiques & Croyants. Paris: Beauchesne Ed., 1990.

Renaissance of Science in Islamic Countries. Singapore and London: World Scientific, 1994.

OTHER SOURCES

Ali, Ahmed, John Ellis, and Seifallah Rabjabar-Daemi. “The Tale of Two Peripheries: The Creation of the International Centre for Theoretical Physics in Trieste.” Historical Studies of Physical and Biological Sciences (Special Issue, Alexis De Greiff and David Kaiser, eds.) 33, part 1 (2002): 33–60.

———. “The Politics of Non-cooperation: The Boycott of the International Centre for Theoretical Physics,” OSIRIS(“Science, Technology and International Affairs: Historical Perspectives,” John Krige and Kai-Henrik Barth, eds.) 21 (2006): 86–109.

———, eds. Salamfestschrift. A Collection of Talks from the Conference on Highlights of Particle and Condensed Matter Physics. Singapore: World Scientific, 1994.

Ellis, John, Faheem Hussain, Thomas Kibble, et al. The Abdus Salam Memorial Meeting. Singapore: World Scientific Publishing, 1999.

Hamende, Andre, ed. From a Vision to a System. The International Centre for Theoretical Physics (1964–1994). Trieste, Italy: International Foundation Trieste for the Progress and the Freedom of Sciences, 1996.

Hoodbhoy, Pervez. “Abdus Salam: Past and Present.” News International, 29 January 1996.

Kibble, Thomas. “Abdus Muhammad Salam.” Biographical Memoirs (Royal Society) 44 (1988): 385–401.

Singh, Jagjit. Abdus Salam: A Biography. Kolkata: Penguin Books, 1992.

Alexis De Greiff A

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