A tribute by Md Asadullah Khan
FOCUS, The Daily Star, Dhaka, Tuesday, December 3, 1996
PROFESSOR Abdus Salam’s death, on November 21, this year in Oxford, the hub of his scientific career, though not premature, must be construed as a tragic loss to the scientific community of the third world countries. Born in a middle class family in Jhang, Punjab in 1926, Salam rose to eminence in life through his commitment to physics and far more through his efforts towards the internationalisation of science, epitomised by the creation of International Centre for Theoretical Physics at Trieste, Italy. With a burning concern, fired by his own unhappiness at having to leave his country for want of funds and opportunities for higher research, Salam was always trying to find ways for those like him to continue working for their own communities. What Professor Salam has envisioned was that there could be no permanent dominance in science by a single nation and that scientific thought and its creation was the common and shared heritage of mankind.
Salam’s greatness lies in the fact that he was able to bring about a synthesis between science and religion. In physics, Salam was mostly involved with symmetries as he says, “That may come from my Islamic heritage for that is the way we consider the universe created by Allah with ideas of beauty and symmetry and harmony, with regularity and without chaos.” Salam often said, “The Quran plays a lot of emphasis on natural law and we are trying to discern, discover and interpret the revelation made through the “Quranic Suras” in respect of nature and its bounties.”
A highly meritorious and intelligent student of the day, Salam did not drift to Civil service, the choicest job in those days in Pakistan. He took a mathematics degree from Lahore, won a unique scholarship to Cambridge and while there “drifted into physics”.
Salam did not come of an affluent family. The way Salam got the scholarship was to him – “something of a miracle”. During the second world war, many Indian politicians wanted to help the British was effort. One of them collected a fund of about 15,000 pounds sterling but the war ended abruptly. With that fund, he instituted five scholarships and Salam was selected for one of these. The other four scholarships could not be availed by anyone since the sudden death of the donor brought about a change in the mind of his successors and the scholarships were cancelled. What Salam, had told about science some years before, still holds true. “Opportunities are so sporadic in the third world that the man who is absolutely a top guy may not get a chance. There is everything against doing science as a profession. It is poorly paid, very little endowed, it carries no influence or status in a status-conscious society.”
In Cambridge, Professor Paul Matthews gave Salam an important problem on “meson” theories. In about five months Salam solved the problem that contributed to renormalising the meson theories and he was awarded Ph D. After the Ph D degree, Salam took up a teaching job at the University of Punjab in Lahore on an yearly salary of 700 pound sterling. There was no tradition of doing any postgraduate work or research nor were there any journals enabling him to stimulate his knowledge nor any opportunity of attending any conferences.
The head of the institution, Salam was serving, told him to forget about research. He was given a choice of three jobs, for any spare time he might have after teaching duties: Bursar, warden of a hall of residence, or president of the football club. Salam chose the football club.
Societal norms at that time worked against any continuation of research work in physics. Salam was faced with a stark dilemma of a choice between physics and Pakistan. This time Salam had opted for physics and returned to Cambridge and took up the job of starting the department of Theoretical Physics in the Imperial College, London. In 1957 he was appointed full professor, Salam threw himself passionately into physics inventing the two component theory of the “neutrino”, working on particle symmetries and in particular “gauge theories” with the objective of bringing about unification of weak and electromagnetic forces as a goal.
With the passionate desire burning in him to fill a void in research work in the developing countries like Pakistan, Professor Salam in 1960 conceived the idea of setting up an International Centre for Theoretical Physics mostly for post-Ph D holders with funds from the international community like the UN.
The centre so set up till now works as an epicentre allowing opportunities for the scientists in the realm of physics, mathematics and electrical engineering to get the latest scientific news, to learn the latest techniques and refresh their ideas about the physics of the day while spending bulk of their time teaching in the home countries. Salam ultimately convinced the IAEA (International Atomic Energy Agency) to take up the charge of the centre.
Professor Salam’s brainchild the ICTP (International Centre for Theoretical Physics) has expanded over the years from fundamental physics to physics of the day suited to the needs of the developing countries with emphasis on solid state physics that helps orientation and development in the industrial sector of the developing countries. True to everybody’s expectation, ICTP is now stressing research in physics of solids, plasma physics, physics of Oceans and the Earth, applicable mathematics, physics of technology, of natural resources together with physics of the frontier.
Professor Salam, in the words of Professor Ziman, a luminary in SSP (Solid State Physics) in the contemporary world, is a man who has dedicated his life to the principle of unity – the unity of nature and the unity of mankind. The various interactions of elementary particles that Professor Salam has seen as a natural philosopher have been interpreted as nothing more than diverse aspects of a single primary force. As a political and moral leader, he has demonstrated that various interactions of nations and cultures are no obstacle to the brotherhood of man in science.
Professor Salam was awarded Nobel prize for his epoch-making theory in the “unification of electro-magnetic and weak interaction that had bedevilled Einstein and in which field namely the “Unified Field Theory” he devoted himself during the last twenty-five years of his life. What Einstein wanted was to unite Maxwell’s electro-magnetism with Newtonian gravity in the same way that Maxwell has united electricity and magnetism. His proposition stated in a simpler form considers all matter, we see around us, to be made up of four building blocks – four basic particles, the proton (P) and the neutron (N) and the two so called light particles the electron (E) and the neutrino, the elusive particle having no mass. There are four basic forces which govern the behaviour of these particles when they come close to each other. These four forces are: (i) Gravitational Force, (ii) Electromagnetic Force, (iii) Weak Nuclear Force, (iv) Strong Nuclear Force.
(i) The Gravitational force that constitutes four particles proton, neutron, electron and neutrino and in which the particles attract each other with a force which is proportional to their mass, controls the planetary motion, motion of the galaxies and stars right up to the falling of a mango from the tree.
(ii) Electro-magnetic force: In this type of force, the protons and electrons being electrically charged attract each other with a force that is proportional to their electric charges. Conspicuously, the other two particles, neutron and neutrino, being electrically neutral play no part in this type of force. This proton-electron force is responsible for holding atoms together. The incandescence of an electric bulb, the swinging of an electric fan and all such phenomenon that constitute our life on earth are governed by this force.
(iii) Weak Nuclear Force: In this type of force, proton, neutron, electron and neutrino interact with each other provided they are closer to each other than 10-16 cm and are in a state of left polarisation. This force which is responsible for Beta decay (Beta-radioactivity) is principally responsible for the existence of heavy elements like Uranium, Radium etc. on earth.
(iv) Strong Nuclear Force: Protons and neutrons carry strong nuclear charge (in addition to the weak nuclear charge). These particles attract each other strongly when they tend to be closer than 10-13 cm. This strong nuclear force is responsible for holding the nucleus of Lithium (Li), Berrylium (Be), Carbon (C) and Uranium (U) etc. together. The phenomenon of fusion responsible for making the sun shine, and fission working in a nuclear reactor that provides electricity in this power starved world, are aspects of this force.
Just as Maxwell and Faraday had shown that the seeming distinction between electricity and magnetism depended on whether electric charges producing these forces were stationary or in motion, in a like manner physicist Salam had hoped that he could unify the four seemingly distinct forces into one single basic force of which the four known ones are different facets. Einstein had wished to see a unification of gravity and electro-magnetism as aspects of one single force. Simply stated, Einstein wished to unite electric charges with gravitational charge (mass) into one single entity.
In writing an epitaph for Professor Salam, it is relevant to recall what Al-kindi wrote about 1130 years ago, “It is fitting for us not to be ashamed to acknowledge truth and to assimilate it from whatever source it comes to us. For him who scales the truth there is nothing of higher value than truth itself, it never cheapens nor abases him.” In the spirit of Al-kindi, we must express our deepest indebtedness to Professor Salam regardless of the consideration of the country, faith and sect he belonged to.
Sadly true, the developing countries like ours are miles apart from the road to science. It stems from our lack of attaching topmost priority to acquisition of knowledge and its dissemination through the community. In an effort to break the scientific isolation of the developing countries and internationalise science, Professor Salam launched an effort to establish the first International Centre in a scientific discipline with a view to increasing the size of high level scientific manpower and breaking their isolation. Salam succeeded in ending the loneliness of such people working in the academically underdeveloped countries. Scientists from all parts of the world gather in Trieste for some months to “plug in” to current excitement of physics, sample the latest ideas and most importantly, meet the world leaders in the subject. The scientists seize this opportunity as a time for renewal, an opportunity to communicate with kindred spirits.