Rouse Ball travelling studentship in mathematics. During this time, nuclear physics was attracting the greatest minds and it was one of the most significant emerging fields as compared to theoretical physics, the opposition towards theoretical physics attacked the field because it was lenient towards theories rather than proving natural phenomenon through experiments. Conducting experiments on particles which also released enormous amounts of radiation, was a lifelong passion of Bhabha, and his leading-edge research and experiments brought great laurels to Indian physicists who particularly switched their fields to nuclear physics, one of the most notable being Piara Singh Gill. Work in nuclear physics In January 1933, Bhabha received his doctorate in nuclear physics after publishing his first scientific paper, "The Absorption of Cosmic radiation". In the paper, 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 he first calculated the cross-section of electron-positron scattering. Electron-positron scattering was later named Bhabha scattering, in honour of his contributions to the field. In 1936, with Walter Heitler, he co-authored 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. Career Starting his nuclear physics career in Britain, Bhabha had returned to