🙏Chandrasekhara Venkata Raman
Chandrasekhara Venkata Raman ( 7 November 1888 – 21 November 1970) was an Indian physicist known mainly for his work in the field of light scattering.With his student K. S. Krishnan, he discovered that when light traverses a transparent material, some of the deflected light changes wavelength and amplitude. This phenomenon was a new type of scattering of light and was subsequently termed as the Raman effect (Raman scattering). Raman won the 1930 Nobel Prize in Physics and was the first Asian person to receive a Nobel Prize in any branch of science.
Born to Hindu Tamil Brahmin parents, Raman was a precocious child, completing his secondary and higher secondary education from St Aloysius' Anglo-Indian High School at the ages of 11 and 13, respectively. He topped the bachelor's degree examination at the University of Madras with honours in physics from Presidency College at age 16. His first research paper, on diffraction of light, was published in 1906 while he was still a graduate student. The next year he obtained an M.A. degree. He was 19 years of age when he joined the Indian Finance Service in Kolkata as Assistant Accountant General. There he became acquainted with the Indian Association for the Cultivation of Science (IACS), the first research institute in India, which allowed him to do independent research and where he made his major contributions in acoustics and optics.
In 1917, he was appointed as the first Palit Professor of Physics by Ashutosh Mukherjee at the Rajabazar Science College under the University of Calcutta. On his first trip to Europe, seeing the Mediterranean Sea motivated him to identify the prevailing explanation for the blue colour of the sea at the time, namely reflected Rayleigh scattered light from the sky, as being incorrect. He founded the Indian Journal of Physics in 1926. He and Krishnan discovered on 28 February 1928 a novel phenomenon of light scattering, which they called "modified scattering," but more famously known as the Raman effect. The day is celebrated by the Government of India as the National Science Day every year. Raman moved to the Indian Institute of Science in Bangalore in 1933 to become its first Indian Director. There he founded the Indian Academy of Sciences the same year. He established the Raman Research Institute in 1948 where he worked to his last days.
In 1954, the Government of India honoured him with the first Bharat Ratna (along with politician C. Rajagopalachari and philosopher Sarvepalli Radhakrishnan), its highest civilian award. He later smashed the medallion in protest against Prime Minister Jawaharlal Nehru's policies on scientific research.
Early life and education
C. V. Raman was born in Tiruchirapalli, Madras Presidency (now Trichy, Tamil Nadu), to Hindu Tamil parents, Chandrasekhara Ramanathan Iyer and Parvathi Ammal. He was the second of eight siblings. His father was a teacher at the local high school, and earned a modest income. He recalled: "I was born with a copper spoon in my mouth. At my birth my father was earning the magnificent salary of ten rupees per month!" In 1892, his family moved to Visakhapatnam (then Vishakapatnam or Vizagapatam or Vizag) in Andhra Pradesh as his father was appointed to the faculty of physics at Mrs AV Narasimha Rao College. There Raman studied at St Aloysius' Anglo-Indian High School. He passed matriculation at age 11 and the FA examination (equivalent to today's Intermediate exam, PUCPDC and +2) with a scholarship at age 13, securing first position in both under the Andhra Pradesh school board examination.
In 1902, Raman joined Presidency College in Madras (now Chennai) where his father had been transferred to teach mathematics and physics. In 1904, he obtained a B.A. degree from the University of Madras, where he stood first and won the gold medal in physics and english. At age 18, while still a graduate student, he published his first scientific paper on "Unsymmetrical diffraction bands due to a rectangular aperture" in the British journal Philosophical Magazine in 1906. He completed an M.A. degree from the same university with highest distinction in 1907. His second paper published in the same journal that year was on surface tension of liquids. It was alongside Lord Rayleigh's paper on the sensitivity of ear to sound, and from which Lord Rayleigh started to communicate with Raman, courteously addressing him as "Professor."
Aware of Raman's capacity, his physics teacher Richard Llewellyn Jones insisted him to continue research in England. Jones arranged for Raman's physical inspection with Colonel (Sir Gerald) Giffard. The inspection revealed that Raman would not withstand the harsh weather of England, the incident of which he later recalled, and said, "[Giffard] examined me and certified that I was going to die of tuberculosis… if I were to go to England."
Career
Raman's elder brother Chandrasekhara Subrahmanya Ayyar had joined the Indian Finance Service (now Indian Audit and Accounts Service), the most prestigious government service in India. (The most coveted service, Indian Civil Service (ICS) was at the time recruited in England.) In no condition to study abroad, Raman followed suit and qualified for the Indian Finance Service with first position in the entrance examination in February 1907. " He was posted in Calcutta (now Kolkata) as Assistant Accountant General in June 1907. It was there that he became highly impressed with the Indian Association for the Cultivation of Science (IACS), the first research institute founded in India in 1876. He immediately befriended Asutosh Dey, who would eventually become his lifelong collaborators, Amrita Lal Sircar, founder and secretary of IACS, and Ashutosh Mukherjee, executive member of the institute and Vice Chancellor of the University of Calcutta. With such a connection, he obtained permission to conduct research in his own time even "at very unusual hours", as Raman later reminisced. Up to that time the institute had not yet recruited regular researchers, or produced any research papers. Raman's article "Newton's rings in polarised light" was published in Nature in 1907 from the institute. His work inspired IACS to publish a journal Bulletin of Indian Association for the Cultivation of Science in 1909 in which Raman was the major contributor.
In 1909, Raman was transferred to Rangoon, Burma (now Myanmar), to take up the position of currency officer. After only a few months, he had to return to Madras as his father succumbed to fatal illness. The subsequent death of his father and funeral rituals made him stay there for the rest of the year. Soon after he resumed office at Rangoon, he was transferred to Nagpur, Maharashtra in 1910.[28] Even before he served for a year in Nagpur, he was promoted to Accountant General in 1911 and again posted to Calcutta.
From 1915, the University of Calcutta started assigning research scholars under Raman at IACS. Sudhangsu Kumar Banerji (who later become Director General of Observatories of India Meteorological Department), a PhD scholar under Ganesh Prasad, was his first student. From the next year, other universities followed suit including University of Allahabad, Rangoon University, Queen's College Indore, Institute of Science, Nagpur, Krisnath College, and University of Madras. By 1919, Raman had guided more than a dozen students. Following Sircar's death in 1919, Raman received two honorary positions at IACS, Honorary Professor and Honorary Secretary. He referred to this period as the "golden era" of his life.
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