the "Raman Effect" ..... Google Special Doodle for Sir CV Raman

Today 7^th Nov … is a great day, the Nation should be remembering and celebrating …..

In the history of science, we often find that the study of some natural phenomenon has been the starting-point in the development of a new branch of knowledge.  Years ago, occurred an instance of this – in the ofrm of colour of skylight, which later was to inspire  numerous optical investigations.  In the words of its creator ~ “Even more striking, though not so familiar to all, is the colour exhibited by oceanic waters. A voyage to Europe in the summer of 1921 gave me the first opportunity of observing the wonderful blue opalescence of the Mediterranean Sea. It seemed not unlikely that the phenomenon owed its origin to the scattering of sunlight by the molecules of the water.”

That path-breaking invention which was to honour and make him a Nobel Laureate – the invention itself came to be known after him ~ it was  the inelastic scattering of a photon. When photons are scattered from an atom or molecule, most photons are elastically scattered, such that the scattered photons have the same energy (frequency and wavelength) as the incident photons.

Here is an extract of the Presentation Speech by Professor H. Pleijel, Chairman of the Nobel Committee for Physics of the Royal Swedish Academy of Sciences, on December 10, 1930……. The Academy of Sciences, has resolved to award the Nobel Prize in Physics for 1930 to Sir ____________________for his work on the scattering of light and for the discovery of the effect named after him.

The diffusion of light is an optical phenomenon, which has been known for a long time. A ray of light is not perceptible unless it strikes the eye directly. If, however, a bundle of rays of light traverses a medium in which extremely fine dust is present, the ray of light will scatter to the sides and the path of the ray through the medium will be discernible from the side. We can represent the course of events in this way; the small particles of dust begin to oscillate owing to electric influence from the ray of light, and they form centres from which light is disseminated in all directions. The wavelength, or the number of oscillations per second, in the light thus diffused is here the same as in the original ray of light. But this effect has different degrees of strength for light with different wavelengths. It is stronger for the short wavelengths than for the long ones, and consequently it is stronger for the blue part of the spectrum than for the red part. Hence if a ray of light containing all the colours of the spectrum passes through a medium, the yellow and the red rays will pass through the medium without appreciable scattering, whereas the blue rays will be scattered to the sides. <http://www.nobelprize.org/nobel_prizes/physics/laureates/1930/press.html>

Sure no more clues and a brilliant google doodle today to honour our own Sir CV Raman.

Sir Chandrasekhara Venkata Raman, FRS  was born on 7^th Nov 1888 and lived till 21^st Nov 1970.  The great Indian physicist’s  work was influential in the growth of science in India. He was the recipient of the Nobel Prize for Physics in 1930 for the discovery that when light traverses a transparent material, some of the deflected light changes in wavelength. This phenomenon is now called Raman scattering and is the result of the Raman effect.

Venkata Raman was born in Thiruvanaikkaval, Trichinopoly [nearer Thiruvarangam – at Trichi].   His parents were R. Chandrasekhara Iyer and Parvati Ammal. He was the second of their five children. At an early age, Raman moved to the city of Visakhapatnam. His father was a lecturer in mathematics and physics at Presidency College in Madras, which Raman entered in 1902 at the age of 13. In 1904 he passed his B.A. examination in first place and won the gold medal in physics, and in 1907 he gained his M.A. degree with the highest distinctions. In 1917, Raman resigned from his government service 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), Calcutta, where he became the Honorary Secretary. Raman used to refer to this period as the golden era of his career.

On 28 February 1928, Raman led experiments at the IACS with collaborators, including K. S. Krishnan, on the scattering of light, when he discovered the Raman effect. Mr K. S. Krishan, surprisingly did not share the award, but is mentioned prominently even in the Nobel lecture.

Raman was president of the 16th session of the Indian Science Congress in 1929. He was conferred a knighthood, and medals and honorary doctorates by various universities. It is stated that Raman was confident of winning the Nobel Prize in Physics as well, but was disappointed when the Nobel Prize went to Richardson in 1928 and tode 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. 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". He was the first Asian to receive any Nobel Prize in the sciences. Before him Rabindranath Tagore (also Indian) had received the Nobel Prize for Literature in 1913. In 1941 he was awarded the Franklin Medal. In 1954 he was awarded the Bharat Ratna.[

He also started a company called Travancore Chemical and Manufacturing Co. Ltd. (now known as TCM Limited) which manufactured Pottasium chlorate for the match industry. 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.

He died in 1970, in Bangalore, at the age of 82. Sir 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.

India celebrates National Science Day on 28 February of every year to commemorate the discovery of the Raman effect in 1928.

Thanks to Google for that special doodle in honour of Sir CV Raman. For the uninformed – Google doodles are special logos that one finds in their home search page.  The  Google logo, many a times animated expressions – keep changing. Google puts special doodles marking special occasions and days.  Google doodles on homepage of the search engine has made it more fun and enjoyable for the users and nobody ever anticipated that it would become so popular. 

With regards – S. Sampathkumar

7^th Nov. 2013.