Chandrasekhara Venkata Raman

Indian physicist

• Born: November 7, 1888; Trichinopoly, India (now Tiruchirapalli, India)
• Died: November 21, 1970; Bangalore, India

Chandrasekhara Venkata Raman, the first internationally acclaimed Indian physicist to be entirely educated within India, was awarded the Nobel Prize in Physics in 1930 for his discovery of important characteristics of light scattering. Raman also made significant contributions to Indian education, establishing the Raman Research Institute in Bangalore in 1948.

PRIMARY FIELD: Physics

SPECIALTIES: Optics; acoustics

Early Life

Chandrasekhara Venkata Raman was born the second-eldest child of Chandrasekhara Iyer, a professor of mathematics and physics, and Parvathi Ammal, who was from a family of well-known Sanskrit scholars. In 1892, while Raman was still a child, his father accepted a position at Mrs. A. V. N. College in Vishakhapatnam in Andhra Pradesh province. There, Raman demonstrated his academic prowess early, finishing his secondary education at eleven years old and immediately entering Mrs. A. V. N. College. Raman completed two years there and entered Presidency College in Madras, where he received his BA in English and physics with honors at age fifteen. He was not well enough to study abroad as his peers did. Instead, he pursued his postgraduate education at Presidency College, publishing his first paper on the physics of light in the British Philosophical Magazine in November 1906 and completing his MA with honors in 1907.

By then, Raman had exhausted the available educational routes in India. Since he was unable to travel, his academic career essentially ended, and he applied to take the Indian civil service examination, on which he scored top marks. Such positions were highly respected and well paid. Before entering the civil service, Raman married Lokasundari Ammal and, in late 1907, moved his new family to Calcutta, where he had been made assistant accountant general.

Before the end of 1907, Raman discovered that only a few blocks from his residence was the Indian Association for the Cultivation of Science. The association had fallen on hard times, chiefly because of lack of interest and attention. Raman brought new life to the organization, spending nearly all of his spare time at the association for the next ten years and actively pursuing his own research interests in a carefully defined research program that he designed chiefly on his own initiative. During those years, Raman published frequently on the physics of stringed instruments and acoustics in such publications as Nature, Bulletin of the Indian Association for the Cultivation of Science, Physical Review, and the Philosophical Magazine.

Life’s Work

By 1917, Raman’s reputation was sufficiently well established that he was offered the Sir Tarakanath Palit chair in physics at the University of Calcutta. Again, however, Raman was required to study abroad, and he refused. Vice Chancellor Asutosh Mookerjee recognized Raman as the ideal person to occupy the new position and was so impressed by Raman’s expertise that he waived the travel requirement, allowing Raman to accept the post. Raman was no longer able to maintain his leadership position at the Indian Association for the Cultivation of Science, however, and his salary dropped significantly. He also shifted from studies on the physics of musical instruments to focus on the physics of light and optics.

Four years after he joined the University of Calcutta, Raman became a full professor, teaching, lecturing, and helping to establish a fully developed graduate curriculum. For the first time in his career, in 1921, Raman traveled outside India to the Congress of Universities of the British Empire in Oxford, England. In England, Raman presented the first of his many lectures to be given abroad to the Physical Society of London about his research activities. On his return to Calcutta, he made the observation that would ultimately lead him to win the Nobel Prize in Physics.

As his ship sailed the Mediterranean Sea, Raman commented on its “wonderful blue opalescence.” He also recognized that the blue was a result of the scattering of the light by the water itself and not the reflection of the sky, as was widely accepted at the time. En route, Raman conducted a simple experiment that confirmed his hypothesis. Soon after his return to Calcutta, he published a paper in Proceedings of the Royal Society entitled “On the Molecular Scattering of Light in Water and the Colour of the Sea.” He was so delighted at uncovering this apparently pristine area of scientific investigation that he began to focus nearly all of his research in uncovering other aspects of the physics of light.

In 1923, Raman and graduate student K. R. Ramanathan were conducting observations in light scattering through highly purified glycerine, when a phenomenon that would later be called the Raman effect was first observed. It was a barely detectable trace of light, shifted to either side of the primary optical spectra of the glycerine.

Raman and his associates first suspected that the very weak secondary reflections that were shifted off the primary spectral trace were the result of impurities in the glycerine. They went to great lengths to purify the glycerine before the light was passed through again. Yet the secondary reflections were still present and undiminished no matter how pure the substance. It became obvious to Raman that these secondary reflections were the result of an inherent characteristic of the matter under investigation. Similar results could be observed in liquids, solids, and gases, but the effect was so weak that conventional methods could not magnify the reflections sufficiently for detailed study.

As Raman’s group raced to understand the effect, they discovered that if they used a mercury arc lamp, which produced a very intense beam of monochromatic (single wavelength) light, they could study the fractional secondary wavelengths reflected. They soon discovered that these secondary reflections revealed aspects of the molecular structure itself. It was a tool of immense importance to physicists and chemists. In 1928, Raman and his colleagues published their results in the Indian Journal of Physics. His discovery was of such consequence that, in only a year’s time, he was designated a knight of the British Empire. In 1930, Raman was awarded the Hughes Medal from the Royal Society and the Nobel Prize in Physics.

Raman was ever devoted to the education of Indian students and knew well that the prominence of his nation in the world depended significantly on its scientific literacy. He founded the Indian Journal of Physics in the mid-1920s and, in 1934, the Indian Academy of Sciences and its publication Proceedings.

In 1933, Raman left his university post to accept the directorship of the Indian Institute of Science in Bangalore, where he gathered a world-class faculty. Unfortunately, he and the board of directors clashed, and after only three years as director, Raman was forced to resign, though remaining a professor until 1948.

That year, Raman accepted the directorship of the newly created Raman Research Institute in Bangalore. India had just gained independence from Great Britain, and Raman was named national professor. Raman and his students continued studies in optics and reflected light. As he studied the reflection of color from roses in his rose gardens, he became fascinated with the physiology of vision. By 1968, he had published forty-three papers on vision in a book entitled The Physiology of Vision.

Raman was awarded the highest honor of the Indian people, the Bharat Ratna (Jewel of India), in 1954. He remained active in the education until his death on November 21, 1970, at the age of eighty-two.

Impact

Raman has been described as one of the last true natural philosophers of science. He was able to bring a conscious love for nature to rigorous scientific investigation, as evidenced by his observations of the blue of the sea, of stringed musical instruments, and even of the color of roses and its relationship to vision. Raman’s guileless approach to science formed the basis for his life’s work, which carried other, far-reaching consequences. Raman’s insistence on remaining in India to complete his education later became the foundation for his motivation to make Indian educational institutions first rate and to provide world-class institutions of learning for Indian students. Raman’s influence on science, education, and the spirit of nationalism in the newly independent nation of India was far-reaching. His personal work in establishing so many of India’s influential publications and institutions has had a profound impact on India’s economic development and social evolution in the world. Furthermore, with the advent of laser technology, the Raman effect has been used extensively to investigate the molecular characteristics of many substances.

Bibliography

"C.V. Raman and the Raman Effect." American Chemical Society, www.acs.org/education/whatischemistry/landmarks/ramaneffect.html. Accessed 11 Oct. 2024.

Levathes, Louise. “Everything Is Illuminated.” Atlantic Monthly305.4 (2010): 32. Print.

Parameswaran, Uma. C. V. Raman: A Biography. New Delhi: Penguin, 2011. Print.

Singh, Rajinder. “C. V. Raman and the Discovery of the Raman Effect.” Physics in Perspective 4.4 (2002): 399–420. Print.

"Sir Chandrasekhara Venkata Raman." Nobel Prize, www.nobelprize.org/prizes/physics/1930/raman/biographical/. Accessed 11 Oct. 2024.