Sir Chandrasekhara Venkata Raman

C. V. Raman was born at Tiruchirapalli in South India on November 7th, 1888. Raman entered Presidency College, Madras, in 1902, and in 1904 passed his B.A. examination, winning the first place and the gold medal in physics; in 1907 he gained his M.A. degree, obtaining the highest distinction. Raman spent 15 years as a Professor in Physics at Calcutta University (1917-32), and 15 years as a Professor in Physics at the Indian Institute of Science, Bangalore (1933-48). In 1948, Raman became the Director of the Raman Institute of Research at Bangalore, established and endowed by himself. On February 28, 1930, Chandrasekhar Venkata Raman discovered the radiation effect involving the inelastic scattering of light that would bear his name- the Raman effect - and which would win him Asia's first Nobel Prize in any Science subject, in 1930. Raman's research interests were in optics and acoustics - the two fields of investigation to which he dedicated his entire career. The main investigations carried out by Raman were: his experimental and theoretical studies on the diffraction of light by acoustic waves of ultrasonic and hypersonic frequencies (published 1934-1942), and those on the effects produced by X-rays on infrared vibrations in crystals exposed to ordinary light. Raman was elected a Fellow of the Royal Society early in his career (1924), and was knighted in 1929. Besides, Raman was honoured with a large number of honorary doctorates and memberships of scientific societies. C. V. Raman passed away in 1970.

 

Prof. Subramanyan Chandrasekhar

Born in Lahore, India, in 1910, theoretical astrophysicist Chandrasekhar was elected to the National Acadamy of Sciences (USA) only two years after he became a US citizen in 1953. Chandrasekhar was noted for his work in the field of stellar evolution, and in the early 1930s he was the first to theorize that a collapsing massive star would become an object so dense that not even light could escape it. Although this finding was greeted with some skepticism at the time it was announced, it went on to form the foundation of the theory of black holes, and eventually earned Chandrasekhar a shared Nobel Prize in physics for 1983. Chandrashekhar estimated the limit (Chandrashekhar limit) on the size of a highly dense variety of star known as 'White Dwarf'. If this star's mass exceeds the limit, it explodes to become a bright supernova. He also made significant contributions to understanding the atmosphere of stars and the way matter and motion are distributed among the stars in the galaxy. Chandrashekar, who recieved the Nobel Prize in 1983, was honoured this year when the largest x-ray telescope aboard the US Space Shuttle was named 'Chandra Telescope'. In addition to his work on star degeneration, Chandrasekhar contributed important theorems on the stability of cosmic masses in the presence of gravitation, rotation, and magnetic fields; this work proved to be crucial for the understanding of the spiral structure of galaxies. From the time he came to the US in 1936 until his death in 1995, Chandrasekhar was affiliated with the University of Chicago and its Yerkes Observatory. Chandrasekhar passed away in 1995.

Prof. Satyendranath Bose

 

Satyendranath Bose was born on the first of January 1894 in Calcutta. He studied at the University of Calcutta, then taught there in 1916, taught at the University of Dacca (1921-45), then returned to Calcutta (1945-56). He did important work in quantum theory, in particular on Planck.html's black body radiation law. Bose sent his work Planck's Law and the Hypothesis of Light Quanta (1924) to Einstein. He wrote a covering letter saying:- Respected Sir, I have ventured to send you the accompanying article for your perusal and opinion. You will see that I have tried to deduce the coefficient .. in Planck's law independent of classical electrodynamics. It was enthusiastically endorsed by Einstein who saw at once that Bose had removed a major objection against light quanta. The paper was translated into German by Einstein and submitted with a strong recommendation to the Zeitschrift f�r Physik. Bose also published on statistical mechanics leading to the Bose-Einstein statistics. Dirac coined the term boson for particles obeying these statistics. Satyendranath Bose and Albert Einstein published a series of papers on the physics of particles with integer spins (bosons). The duo predicted that if a collection of bosonic atoms could be cooled to the point that each one reaches its lowest possible quantum mechanical energy, a Bose-Einstein condensate would result. In this state, atoms would lose their individual properties and would act collectively as a single entity. Satyendranath Bose passed away in 1974.

 

Srinivasa Iyengar Ramanujan

 

Srinivas Ramanujan was born on December 22, 1887 in his grandmother's house in Erode, Tamil Nadu. In January 1913 Ramanujan wrote to G. H. Hardy having seen a copy of his 1910 book Orders of Infinity. In Ramanujan's historic first letter to Hardy, he introduced himself and his work of about 100 theorems. In 1914, Hardy brought Ramanujan to Trinity College, Cambridge, to begin an extraordinary collaboration between two mathematicians. On 16 March, 1916 Ramanujan graduated from Cambridge with a Bachelor of Science by Research (the degree was called a Ph.D. from 1920). Ramanujan's dissertation was on Highly Composite Numbers and consisted of seven of his papers published in England. Ramanujan would go on to publish 26 papers in British journals. On May 2, 1918, Srinivasa Iyengar Ramanujan was elected Fellow of the Royal Society of London. He would be the first Indian and first Asian to be elected so. Srinivasa Ramanujan was one of India's greatest mathematical geniuses. He made substantial contributions to the analytical theory of numbers and worked on elliptic functions, continued fractions, and infinite series. Ramanujan's work on partial sums and products of hypergeometric series led to major development in the topic. He gave his name to two constants, the Landau-Ramanujan constant and the Nielsen-Ramanujan constant. Ramanujan died on April 26, 1920 at the age of 33 in Kumbakonam, Tamil Nadu. Before he died, Ramanujan wrote down about 600 theorems on loose sheets of paper, which were discovered and published only in 1976 as the "Lost Notebook" of Ramanujan.  

 

Sir Jagdish Chandra Bose

Born in Mymensingh, Bengal, in November 30, 1858, Bose went to England to study medicine at the University of London. He returned to India with a B.A degree from Cambridge and a B.Sc from the London University and started experiments involving refraction, diffraction and polarisation. Sir J.C. Bose did his original scientific work in the area of Microwaves.  He produced extremely short waves and done considerable improvement upon Hertz's detector of electric waves. He produced a compact appratus for generating electromagnetic waves of wavelengths 25 to 5 mm and studying their quasioptical properties, such as refraction, polarization and double refraction. Bose turned his attention from electromagnetic waves to response phenomena in plants by the end of the 19th century. Bose's research on response in living and non-living led to some significant findings: in some animal tissues like muscles, stimulation produces change in form as well as electrical excitation, while in other tissues (nerves or retina), stimulation by light produces electric changes only but no change of form. He showed that not only animal but vegetable tissues under different kinds of stimuli-mechanical, application of heat, electric shock, chemicals, drugs- produce similar electric responses. He was appointed Professor Emeritus after he retired from the Presidency College in 1915. The Bose Institute was founded a couple of years later. He was also elected Fellow of the Royal Society in 1920. In 1937 Jagdish Chandra Bose passed away at Giridih in Bihar.  

  

 

Meghnad Saha was born on October 6, 1893 in Sheoratali, a village in the District of Dacca, now in Bangladesh. In 1911, he came to Calcutta to study in Presidency College. Meghnad became famous after his article on solar chromosphere ion' was published in 'Astrophysical journal' in 1920. He came to be recognised as a scientist of substance. In 1920, he went to England to prove his theory before the global scientific community. He went to Prof. Alexander Fowler and Prof. Walter Nurnst of Germany. Two years later, he came back and joined the University of Calcutta as the Khaira Professor. In 1927, Meghnad was elected as a fellow of London's Royal Society.He invented an instrument to measure the weight and pressure of solar rays. He produced the famous equation which he called 'equation of the reaction - isobar for ionization' which later became known as Saha's "Thermo-Ionization Equation". Saha was the leading spirit in organizing the scientific societies like the 'National Academy of Science' (1930), 'Indian Institute of Science' (1935) and the 'Indian Association for the Cultivation of Science' (1944). The lasting memorial to him is the 'Saha Institute of Nuclear Physics' founded in 1943 in Calcutta. He was the chief architect of river planning in India. He prepared the original plan for Damodar Valley Project. Saha passed away in 1956.