Wednesday, July 9, 2008

Homi Jehangir Bhabha


Homi Jehangir Bhabha, FRS (October 30, 1909 – January 24, 1966) was an Indian nuclear physicist of Parsi-Zorastrian heritage who had a major role in the development of the Indian atomic energy program and is considered to be the father of India's nuclear program. Bhabha was born into a prominent family, through which he was related to Dinshaw Maneckji Petit, Muhammad Ali Jinnah, Homi K Bhabha and Dorab Tata. After receiving his early education at Bombay schools and at the Royal Institute of Science, he attended Caius College of Cambridge University to pursue studies in mechanical engineering. After taking the mechanical engineering Tripos, he pursued studies under Paul Dirac to complete the Mathematics Tripos. Meanwhile, he worked at the Cavendish Laboratory while working towards his doctorate in theoretical physics under R. H. Fowler. During this time, he embarked on groundbreaking research into the absorption of cosmic rays and electron shower production. Afterwards, he published a string of widely-accepted papers on his theories regarding cosmic ray showers.
World War II broke out in September 1939 while Bhabha was vacationing in India. He chose to remain in India until the war ended. In the meantime, he accepted a position at the Indian Institute of Science in Bangalore, headed by Nobel laureate C. V. Raman. He established the Cosmic Ray Research Unit at the institute, and began to work on the theory of the movement of point particles. In 1945, he established the Tata Institute of Fundamental Research in Bombay, and the Atomic Energy Commission of India three years later. In the 1950s, Bhabha represented India in International Atomic Energy Forums, and served as President of the United Nations Conference on the Peaceful Uses of Atomic Energy in Geneva, Switzerland in 1955. He later served as the member of the Indian Cabinet's Scientific Advisory Committee and set up the Indian National Committee for Space Research with Vikram Sarabhai. In January 1966, Bhabha died in a plane crash near Mont Blanc, while heading to Vienna, Austria to attend a meeting of the International Atomic Energy Agency's Scientific Advisory Committee.
Early life
Bhabha was born in Bombay to Jehangir Hormaji Bhabha, an Oxford-educated barrister, and Meherbai Framji Panday, a wealthy Parsi family living in Bombay, India Bhabha, at his birth, was directly linked to India's most prominent mercantile families.[1] Through his mother, Bhabha was the great-grandson of Sir Dinshaw Maneckji Petit, a textiles entrepreneur noted for his philanthropic efforts,[2] and therefore distantly related by marriage to Muhammad Ali Jinnah through his second wife, Rattanbai Petit, who was the elder Petit's granddaughter. Through his father, Bhabha was the grandson of Hormusji Bhabha, CIE, the Inspector-General of Education in Mysore, and the nephew of Meherbai Hormusji, who was married to Dorab Tata, the eldest son of Jamsetji Tata.[1] He is also a distant relative of similarly named post-colonial theorist Homi K Bhabha.[3]
Bhabha received his early education at Bombay's Cathedral Grammar School[1], which became the Cathedral and John Connon School in 1922 after merging with the John Connon School, run by the city's Scottish Education Society. He entered Elphinstone College at age 15 after passing his Senior Cambridge Examination with Honours. He then attended the Royal Institute of Science until 1927 before joining Caius College of Cambridge University, the alma mater of his uncle Dorab Tata.[2] His father and uncle Dorab planned for Bhabha to obtain an engineering degree from Cambridge and then return to India, where would join the Tata Iron and Steel Company in Jamshedpur. However, during his studies, Bhabha felt more of an interest in the field of mathematics, instead of engineering. In 1928, Bhabha wrote to his father, informing him of his mixed feelings about his intended specialty:

I seriously say to you that business or job as an engineer is not the thing for me. It is totally foreign to my nature and radically opposed to my temperament and opinions. Physics is my line. I know I shall do great things here. For, each man can do best and excel in only that thing of which he is passionately fond, in which he believes, as I do, that he has the ability to do it, that he is in fact born and destined to do it. My success will not depend on what A or B thinks of me. My success will be what I make of my work. Besides, India is not a land where science cannot be carried on.[1]
I am burning with a desire to do physics. I will and must do it sometime. It is my only ambition. I have no desire to be a 'successful' man or the head of a big firm. There are intelligent people who like that and let them do it. I hear you saying 'But you are not Socrates or Einstein'. No—and that is what Berlioz's father said to Berlioz. He called him a useless musician when he was young—Hector Berlioz who now accepted as one of the world's greatest geniuses and France's greatest musician. How can anybody else know at what time what one will do, if there is nothing to show. ... It is no use saying to Beethoven 'You must be a scientist for it is great thing' when he did not care two hoots for science; or to Socrates 'Be an engineer; it is work of intelligent man'. It is not in the nature of things. I therefore earnestly implore you to let me do physics.

Higher education and research at Cambridge
Bhabha's father understood his son's predicament, and he agreed to finance his studies in mathematics provided that he obtain first class on his Mechanical Sciences Tripos exam. Bhabha took the Tripos exam in June 1930 and passed with first class. Afterwards, he embarked on his mathematical studies under Paul Dirac, the Lucasian Professor of Mathematics who would later be awarded the Nobel Prize in Physics with Erwin Schrödinger in 1933 "for the discovery of new productive forms of atomic theory", while working as a research student in theoretical physics at the Cavendish Laboratory.[1] At the time, the laboratory was the center of a number of scientific breakthroughs. James Chadwick had discovered the neutron, John Cockcroft and Ernest Walton transmuted lithium with high-energy protons, and Patrick Blackett and Giuseppe Occhialini used cloud chambers to demonstrate the production of electron pairs and showers by gamma radiation. During the 1931–1932 academic year, Bhabha was awarded the Salomons Studentship in Engineering. In 1932, he obtained first class on his Mathematical Tripos and was awarded the Rouse Ball travelling studentship in mathematics. With the studentship, he worked with Wolfgang Pauli in Zürich, Enrico Fermi in Rome and Hans Kramers in Utrecht.
Research in theoretical physics
In January 1933, Bhabha published his first scientific paper, "Zur Absorption der Höhenstrahlung" (translates to "The Absorption of Cosmic Radiation"), in the German academic journal entitled Zeitschrift für Physik (Journal of Physics). In the publication, Bhabha offered an explanation of the absorption features and electron shower production in cosmic rays. The paper helped him win the Isaac Newton Studentship in 1934, which he held for the next three years. The following year, he completed his doctoral studies in theoretical physics under Ralph H. Fowler.[5][9] During his studentship, he split his time working at Cambridge and with Niels Bohr in Copenhagen. In 1935, Bhabha published a paper in the Proceedings of the Royal Society, Series A, in which performed the first calculation to determine the cross section of electron-positron scattering. Electron-positron scattering was later named Bhabha scattering, in honor of his contributions in the field. In 1936, Bhabha collaborated with Walter Heitler to formulate a theory on cosmic ray showers. They conjectured that the showers were formed by the cascade production of gamma rays and positive and negative electron pairs. In this process, high energy electrons passing through matter would turn into high energy photons by means of the bremsstrahlung process. The photons then produced a positive and negative electron pair, which then led to additional production of photons. This process continued until the energy of the particles went below a critical value.
In 1936, the two published a paper, "The Passage of Fast Electrons and the Theory of Cosmic Showers" in the Proceedings of the Royal Society, Series A, in which they used their theory to describe how primary cosmic rays from outer space interact with the upper atmosphere to produce particles observed at the ground level. Bhabha and Heitler then made numerical estimates of the number of electrons in the cascade process at different altitudes for different electron initiation energies. The calculations agreed with the experimental observations of cosmic ray showers made by Bruno Rossi and Pierre Victor Auger a few years before. Bhabha later concluded that observations of the properties of such particles would lead to the straightforward experimental verification of Albert Einstein's theory of relativity. In 1937, Bhabha was awarded the Senior Studentship of the 1851 Exhibition, which helped him continue his work at Cambridge until the outbreak of World War II in 1939.
In 1939, Bhabha went back to India for a brief holiday. In September, World War II broke out, and Bhabha decided not to return to England for the time being. He accepted an offer to serve as the Reader in the Physics Department of the Indian Institute of Science, then headed by renowned physicist C. V. Raman. He received a special research grant from the Sir Dorab Tata Trust, which he used to establish the Cosmic Ray Research Unit at the institute. Bhabha selected a few students, including Harish-Chandra, who would later serve as the IBM von Neumann Professor in the School of Mathematics at the Institute for Advanced Study, to work with him.[10]
He was elected a Fellow of the Royal Society on 20 March 1941. With the help of J. R. D. Tata, he established the Tata Institute of Fundamental Research in Bombay. With the end of the World War II and Indian Independence, he received a commendation from Jawaharlal Nehru for his efforts towards peaceful development of atomic energy. He established the Atomic Energy Commission of India in 1948. He represented India in International Atomic Energy Forums, and as President of the United Nations Conference on the Peaceful Uses of Atomic Energy, in Geneva, Switzerland in 1955.
[edit] Death and legacy
He died in the Air India Flight 101 air disaster near Mont Blanc in 1966. Conspiracy theories point to a sabotage intended at impeding India's nuclear program, but his death still remains a mystery.
After his death, the Atomic Energy Establishment was renamed as the Bhabha Atomic Research Centre in his honour. Bhabha also encouraged research in electronics, space science, radio astronomy and microbiology. The famed radio telescope at Ooty, India was his initiative, and it became a reality in 1970. Bhabha has since become known as the "Father of India's Atomic Energy Programme".

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