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An Eye for An Eye!

Man Who Made A Change For India, For The Betterment Of Our Future: Let Us Discover The Raman Effect!

Hello world

blind man

Sir Chandrashekhara Venkata Raman 7 November 1888 ? 21 November 1970) was an Indian physicist born in the former Madras Province in India (presently the state of Tamil Nadu), who carried out ground-breaking work in the field of light scattering, which earned him the 1930 Nobel Prize for Physics. He discovered that when light traverses a transparent material, some of the deflected light changes wavelength and amplitude. This phenomenon, subsequently known as Raman scattering, results from the Raman effect. In 1954, the Indian government honored him with India's highest civilian award, the Bharat Ratna.

C. V. Raman was born in Trichy, Tamil Nadu to Brahmin parents, Chandrashekaran Ramanathan Iyer and Parvathi Ammal. Raman's father was a lecturer who taught mathematics and physics in Mrs. A.V. Narasimha Rao College in Visakhapatnam (then Vishakapatnam) in the Indian state of Andhra Pradesh, and later joined Presidency College in Madras (now Chennai).

At an early age, Raman moved to the city of Visakhapatnam and studied at St Aloysius Anglo-Indian High School. Raman passed matriculation at age 11 and the FA examination (equivalent to today's Intermediate exam, PUCPDC and +2) with a scholarship at age 13.

In 1902, Raman joined Presidency College in Madras where his father was a Lecturer in Mathematics and Physics. In 1904 he obtained a BA degree from the University of Madras, where he stood first and won the gold medal in Physics. In 1907 he completed an MSc degree at the University of Madras with the highest distinction.

Career

Discovery of the Raman effect

In the year 1917, Raman resigned from his government service[clarification needed] after he was appointed the first Palit Professor of Physics at the University of Calcutta. At the same time, he continued doing research at the Indian Association for the Cultivation of Science (IACS) in Calcutta, where he became the Honorary Secretary. Raman referred to this period as the golden era of his career. In 1926 Prof. Raman established the Indian Journal of Physics as the first editor.[9] The second volume of the Journal published his famous article "A New Radiation",[10] reporting the discovery of the Raman Effect.

Energy level diagram showing the states involved in Raman signal

Raman at the 1930 Nobel Prize Award Ceremony with other winners, from left C. V. Raman (physics), Hans Fischer (chemistry), Karl Landsteiner (medicine) and Sinclair Lewis (literature) On 28 February 1928, Raman led an experiment with K. S. Krishnan, on the scattering of light, when he discovered what now is called the Raman effect.[11] A detailed account of this period is reported in the biography by G. Venkataraman.[6] It was instantly clear that this discovery was of huge value. It gave further proof of the quantum nature of light. Raman had a complicated professional relationship with K. S. Krishnan, who surprisingly did not share the award, but is mentioned prominently even in the Nobel lecture.[12]

The field of Raman spectroscopy came to be based on this phenomenon, and Ernest Rutherford referred to it in his presidential address to the Royal Society in 1929. Raman was president of the 16th session of the Indian Science Congress in 1929. He was conferred a knighthood, medals and honorary doctorates by various universities. Raman was confident that he would win the Nobel Prize in Physics as well but was disappointed when the Nobel Prize went to Owen Richardson in 1928 and to Louis de Broglie in 1929. He was so confident of winning the prize in 1930 that he booked tickets in July, even though the awards were to be announced in November, and would scan each day's newspaper for announcement of the prize, tossing it away if it did not carry the news.[13] He did eventually win the 1930 Nobel Prize in Physics "for his work on the scattering of light and for the discovery of the Raman effect".[14] He was the first Asian and first non-white to receive any Nobel Prize in the sciences. Before him Rabindranath Tagore (also Indian) had received the Nobel Prize for Literature in 1913.

Later work

Raman and Suri Bhagavantam determined the spin of photons in 1932, which further confirmed the quantum nature of light.[15]

Raman had association with the Banaras Hindu University in Varanasi; he attended the foundation ceremony of BHU[16] and delivered lectures on Mathematics and "Some new paths in physics" during the lecture series organised at BHU from 5 to 8 February 1916.[17] He also held the position of permanent visiting professor at BHU.[18]

Raman also worked on the acoustics of musical instruments. He worked out the theory of transverse vibration of bowed strings, on the basis of superposition of velocities. He was also the first to investigate the harmonic nature of the sound of Indian drums such as the tabla and the mridangam.[19] He was also interested in the properties of other musical instruments based on forced vibrations such as the violin. He also investigated the propagation of sound in whispering galleries.[20] Raman's work on acoustics was an important prelude, both experimentally and conceptually, to his later work on optics and quantum mechanics.[21]

Raman and his student, Nagendra Nath, provided the correct theoretical explanation for the acousto-optic effect (light scattering by sound waves), in a series of articles resulting in the celebrated Raman?Nath theory.[22] Modulators, and switching systems based on this effect have enabled optical communication components based on laser systems.

Raman was succeeded by Debendra Mohan Bose as the Palit Professor in 1932. In 1933, Raman left IACS to join Indian Institute of Science in Bangalore as its first Indian director.[23] Other investigations carried out by Raman were 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.

During his tenure at IISc, he recruited G. N. Ramachandran, who later went on to become a distinguished X-ray crystallographer.

He also started a company called Travancore Chemical and Manufacturing Co. Ltd. (now known as TCM Limited) which manufactured potassium chlorate for the match industry[24] in 1943 along with Dr. Krishnamurthy.[who?] The Company subsequently established four factories in Southern India. In 1947, he was appointed as the first National Professor by the new government of Independent India.[25]

In 1948, Raman, through studying the spectroscopic behaviour of crystals, approached in a new manner fundamental problems of crystal dynamics. He dealt with the structure and properties of diamond, the structure and optical behaviour of numerous iridescent substances including labradorite, pearly feldspar, agate, opal, and pearls. Among his other interests were the optics of colloids, electrical and magnetic anisotropy, and the physiology of human vision.

Raman retired from the Indian Institute of Science in 1948 and established the Raman Research Institute in Bangalore a year later. He served as its director and remained active there until his death in 1970, in Bangalore, at the age of 82.

Personal life

Raman was married on 6 May 1907 to Lokasundari Ammal (1892?1980).[26] They had two sons, Chandrashekhar and radio-astronomer Radhakrishnan.

Raman was the paternal uncle of Subrahmanyan Chandrasekhar, who later won the Nobel Prize in Physics (1983) for his discovery of the Chandrasekhar limit in 1931 and for his subsequent work on the nuclear reactions necessary for stellar evolution.[27]

Throughout his life, Raman developed an extensive personal collection of stones, minerals, and materials with interesting light-scattering properties, which he obtained from his world travels and as gifts.[28] He often carried a small, handheld spectroscope to study specimens.[29] These are on display at the Raman Research Institute, where he worked and taught.



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