Homi J. Bhabha

Not to be confused with Homi K. Bhabha

Homi Jehangir Bhabha, FRS (30 October 1909 – 24 January, 1966) was an Indian nuclear physicist who played 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 mechanical engineering, 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. Afterward, 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 was awarded Padma Bhushan by Government of India in 1954. 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 received his early education at Bombay's Cathedral Grammar School, 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.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.

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",. 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. 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 protons 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.

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. Homi J. Bhabha was also a close friend of Jawaharlal Nehru and he, along with Prime Minister Jawaharlal Nehru, had played a significant role for developing the Indian nuclear program as well as education reforms in India. Bhaba founded and directed two major scientific institutions - the Tata Institute of Fundamental Research (TIFR) and the Atomic Energy Commission (AEC)of India^[1]. 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.

Death and legacy

He died when Air India Flight 101 crashed near Mont Blanc in January 1966.

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". The Homi Bhabha Fellowship Council has been giving the Homi Bhabha Fellowships since 1967 Other noted institutions in his name are the Homi Bhabha National Institute, an Indian deemed university and the Homi Bhabha Centre for Science Education, Mumbai, India.

References

1. ↑ Ramachandra Guha (2008). India After Gandhi, page 216. Pan Macmillan Ltd., London. 

External References

• Annotated Bibliography for Homi J. Bhabha from the Alsos Digital Library for Nuclear Issues