Satyendra Nath Bose in Paris 1925
Although more than one Nobel Prize was awarded for research related to the concepts of the boson, Bose–Einstein statistics and Bose–Einstein condensate—the latest being the 2001 Nobel Prize in Physics, which was given for advancing the theory of Bose–Einstein condensates—Bose himself was not awarded the Nobel Prize. Among his other talents, Bose spoke several languages and could also play the esraj, a musical instrument similar to a violin.
In his book, The Scientific Edge, the noted physicist Jayant Narlikar observed (Narlikar, 2003):
“S. N. Bose’s work on particle statistics (c. 1922), which clarified the behaviour of photons (the particles of light in an enclosure) and opened the door to new ideas on statistics of Microsystems that obey the rules of quantum theory, was one of the top ten achievements of 20th century Indian science and could be considered in the Nobel Prize class.”
Early life and career
Bose was born in Calcutta, British India, the eldest of seven children. His father, Surendranath Bose, worked in the Engineering Department of the East Indian Railway Company. Bose attended Hindu School in Calcutta, and later attended Presidency College, also in Calcutta, earning the highest marks at each institution. He came in contact with teachers such as Jagadish Chandra Bose and Prafulla Chandra Roy who provided inspiration to aim high in life. From 1916 to 1921 he was a lecturer in the physics department of the University of Calcutta. In 1921, he joined the department of Physics of the then recently founded Dhaka University (now in Bangladesh and called University of Dhaka) (BANC, 2011).
In 1924, while working as a Reader at the Physics Department of the University of Dhaka, Bose wrote a paper deriving Planck's quantum radiation law without any reference to classical physics and using a novel way of counting states with identical particles. This paper was seminal in creating the very important field of quantum statistics. After initial setbacks to his efforts to publish, he sent the article directly to Albert Einstein in Germany. Einstein, recognizing the importance of the paper, translated it into German himself and submitted it on Bose's behalf to the prestigious Zeitschrift für Physik. As a result of this recognition, Bose was able to leave India for the first time and spent two years in Europe, during which he worked with Louis de Broglie, Marie Curie, and Einstein (Grigrious, 2010).
After his stay in Europe, Bose returned to Dhaka in 1926. He became a professor and was made head of the Department of Physics, and continued teaching at Dhaka University until 1945. He was also Dean of the Faculty of Science at Dhaka University for a long period. When the partition of India became imminent, he returned to Calcutta and taught at Calcutta University until 1956, when he retired and was made professor emeritus (Chatterjee & Chatterjee, 2002).
Bose–Einstein statistics
Bose was an ardent follower of Einstein’s ideas and decided to attempt another derivation of Planck’s law of radiation without using any Maxwellian wave theory of radiation. He had read Planck’s work on the distribution of energy from a black body based on this new theory. Satyendra Nath had always been a perfectionist and would not accept any ad hoc assumption while working out a theory. So he was not happy with Planck’s derivation which had such ad hoc assumptions (Chatterjee & Chatterjee, 2002).
While presenting a lecture at the University of Dhaka on the theory of radiation and the ultraviolet catastrophe, Bose attempted a statistical explanation of the interaction of atoms and radiation using the principle, recently developed by Werner Heisenberg, of uncertainty concerning the characteristics of electrons around the atomic nucleus (Walker A. R., 2011). During this lecture, Bose committed an error in applying the theory, which unexpectedly gave a prediction that agreed with the experiment. He adapted this lecture into a short paper called “Planck's Law and the Hypothesis of Light Quanta”.
The error was a simple mistake—similar to arguing that flipping two fair coins will produce two heads one-third of the time—that would appear obviously wrong to anyone with a basic understanding of statistics. However, the results it predicted agreed with experiment, and Bose realized it might not be a mistake at all. He for the first time took the position that the Maxwell–Boltzmann distribution would not be true for microscopic particles where fluctuations due to Heisenberg's uncertainty principle will be significant. Thus he stressed the probability of finding particles in the phase space, each state having volume , and discarding the distinct position and momentum of the particles (Grigrious, 2010).
When Bose sent his paper to Philosophical Magazine (Chatterjee & Chatterjee, 2002) for publication it was rejected because the editors thought he had made a simple mistake in his calculations. So he sent a copy to Einstein, soliciting his opinion. (Walker A. R., 2011). Here is what Bose wrote in his first letter to Einstein (Chatterjee & Chatterjee, 2002):
“I have ventured to send you the accompanying article for your perusal and opinion. I am anxious to know what you think of it. You will see that I have tried to deduce the coefficient in Planck’s laws, independent of the classical electrodynamics, only assuming that the ultimate elementary regions in the phase space had the content . I do not know sufficient German to translate the paper. If you think the paper worth publication, I shall be grateful if you arrange for its publication in Zeitschrift fur Physik. Though a complete stranger to you, I do not feel any hesitation in making such a request. Because we are all your pupils though profiting only by your teachings through your writings. I do not know whether you still remember that somebody from Calcutta asked your permission to translate your papers on relativity in English. You acceded to the request. The book has since been published. I was the one who translated your paper ‘Generalised Relativity’.”
Einstein approved. His theory finally achieved respect when Einstein sent his own paper in support of Bose's to Zeitschrift für Physik, asking that they be published together (Walker A. R., 2011). This was done in 1924. Very soon the paper was published, translated by Einstein, and with the following translator’s remark (Chatterjee & Chatterjee, 2002):
“In my opinion Bose’s derivation of the Planck formula signifies an important development. The method considered here yields also the quantum theory of ideal gases which I shall discuss elsewhere.”
The reason Bose's "mistake" produced accurate results was that since photons are indistinguishable from each other, one cannot treat any two photons having equal energy as being two distinct identifiable photons. By analogy, if in an alternate universe coins were to behave like photons and other bosons, the probability of producing two heads would indeed be one-third ( ). But what Bose actually did was more than derive a formula. He introduced new concepts in physics Bose's "error" (Grigrious, 2010), later named as Bose Statistics. Einstein understood the significance of it and immediately applied it to the case of ideal gas and found a new relation known as Bose-Einstein Statistics (Chatterjee & Chatterjee, 2002).
Einstein adopted the idea and extended it to atoms. This led to the prediction of the existence of phenomena which became known as Bose-Einstein condensate, a dense collection of bosons (which are particles with integer spin, named after Bose), which was demonstrated to exist by experiment in 1995 (Grigrious, 2010).
Later work
Bose's ideas were afterwards well received in the world of physics, and he was granted leave from the University of Dhaka to travel to Europe in 1924 (Grigrious, 2010). He spent a year in France and worked with Marie Curie, and met several other well-known scientists. He then spent another year abroad, working with Einstein in Berlin. Upon his return to Dhaka, he was made a professor in 1926. He did not have a doctorate, and so ordinarily he would not be qualified for the post, but Einstein recommended him. His work ranged from X-ray crystallography to unified field theories. He also published an equation of state for real gases with Megh Nad Saha (Chatterjee & Chatterjee, 2002).
When Satyendra Nath returned to Dacca from Europe in 1926, the post of the professor of physics at the Dacca University was vacant. The selection committee recommended the name of D.M. Bose as its first choice and that of S.N. Bose as its alternative choice. D.M. Bose was then the Ghose professor of physics at Calcutta. He was comfortably settled in his research work and was also in close touch with his uncle, Sir J.C Bose and his research laboratory, the Bose Institute, adjacent to the University College of Science and Technology. Since D.M. Bose did not accept the position offered to him by the Dacca University, Satyendra Nath became the professor of physics at Dacca University, where he continued till 1945 (Chatterjee & Chatterjee, 2002).
Apart from physics he did some research in biochemistry and literature (Bengali, English). He made deep studies in chemistry, geology, zoology, anthropology, engineering and other sciences. Being an Indian of Bengali descent, he devoted a lot of time to promoting Bengali as a teaching language, translating scientific papers into it, and promoting the development of the region (Grigrious, 2010).
In 1944 Bose was elected General President of the Indian Science Congress. In 1958 he became a Fellow of the Royal Society.
Works Cited
BANC. (2011). Satyendra Nath Bose . Retrieved August 1, 2011, from Bengali Association of North Carolina: www.banc-online.org/pdfs/SNB.pdf
bosonparticle.com. (2011). Articles about boson particle. Retrieved August 1, 2011, from Boson Particle: http://www.bosonparticle.com/articles
Chatterjee, S., & Chatterjee, E. (2002). Satyendra Nath Bose. National Book Trust.
Grigrious, V. I. (2010, February). Satyendra Nath Bose. Bhouthika Jyothi, 6(Ruby Jubilee Special), p. 41.
Narlikar, J. V. (2003). The Scientific Edge. Penguin Books.
NIC. (2005). Padma Vibhushan Awardees. (National Informatics Centre, Government of India.) Retrieved August 1, 2011, from india.gov.in: http://india.gov.in/myindia/padmavibhushan_awards_list1.php?start=250
Walker, A. R. (2011). From black bodies to bar codes: lasers. In Magical inventions or the art of discovery. Unpublished.
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