Editing Satyendra Nath Bose (section)

==Research career==
Bose attended [[Hindu School]] in [[Calcutta]], and later [[List of Kolkata Presidencians|attended]] [[Presidency College, Kolkata|Presidency College]], also in Calcutta, earning the highest marks at each institution, while fellow student and future astrophysicist [[Meghnad Saha]] came second.<ref name = SMahanti>{{cite web | first = Dr Subodh | last = Mahanti | place = [[India|IN]] | title = Satyendra Nath Bose, The Creator of Quantum Statistics | url = http://www.vigyanprasar.gov.in/scientists/snbose/bosenew.htm | publisher = Vigyan Prasar | access-date = 1 February 2012 | archive-date = 10 April 2016 | archive-url = https://web.archive.org/web/20160410165124/http://www.vigyanprasar.gov.in/scientists/snbose/bosenew.htm | url-status = live }}</ref> He came in contact with teachers such as [[Jagadish Chandra Bose]], Prafulla Chandra Ray and Naman Sharma who provided inspiration to aim high in life. From 1916 to 1921, he was a lecturer in the [[Academic department|physics department]] of the [[Rajabazar Science College]] under [[University of Calcutta]]. Along with Saha, Bose prepared the first book in English based on German and French translations of original papers on Einstein's special and general relativity in 1919.

In 1921, Satyendra Nath Bose joined as [[Reader (academic rank)|Reader]] in the Department of Physics of the recently founded [[University of Dhaka]] (in present-day Bangladesh).<ref name=Banglapedia>{{citation |author=Md Mahbub Murshed |chapter=Bose, Satyendra Nath |chapter-url=http://en.banglapedia.org/index.php?title=Bose,_Satyendra_Nath |title=Banglapedia: National Encyclopedia of Bangladesh |editor=Sirajul Islam and Ahmed A. Jamal |publisher=[[Asiatic Society of Bangladesh]] |year=2012 |edition=Second |access-date=6 July 2016 |archive-date=7 January 2019 |archive-url=https://web.archive.org/web/20190107004743/http://en.banglapedia.org/index.php?title=Bose,_Satyendra_Nath |url-status=live }}</ref> Bose set up whole new departments, including laboratories, to teach advanced courses for MSc and BSc honours and taught [[thermodynamics]] as well as [[James Clerk Maxwell]]'s [[A Dynamical Theory of the Electromagnetic Field|theory]] of [[electromagnetism]].{{sfn|Wali|2009|pp =xvii, xviii, xx}}

Bose, along with Indian Astrophysicist [[Meghnad Saha]], presented several papers in theoretical physics and pure mathematics from 1918 onwards. In 1924, whilst a Reader in the Physics Department of the [[University of Dhaka]], Bose wrote a paper deriving [[Planck's law|Planck's quantum radiation law]] without any reference to [[classical physics]] by using a novel way of counting states with [[identical particles]]. This paper was seminal in creating the important field of [[quantum statistics]].<ref>{{cite journal|doi=10.1007/BF03010400|url=http://hermes.ffn.ub.es/luisnavarro/nuevo_maletin/Bose_1924.pdf|bibcode=1994JApA...15....3B|title=Planck's Law and the Light Quantum Hypothesis|journal=Journal of Astrophysics and Astronomy|volume=15|pages=3–7|last1=Bose|first1=S. N.|year=1994|s2cid=121808581|access-date=2 February 2018|archive-date=11 October 2021|archive-url=https://web.archive.org/web/20211011075916/http://hermes.ffn.ub.es/luisnavarro/nuevo_maletin/Bose_1924.pdf|url-status=live}}</ref> Though not accepted at once for publication, he sent the article directly to [[Albert Einstein]] in Germany. Einstein, recognising the importance of the paper, translated it into German himself and submitted it on Bose's behalf to the ''[[Zeitschrift für Physik]]''. As a result of this recognition, Bose was able to work for two years in European [[X-ray]] and [[crystallography]] laboratories, during which he worked with [[Louis de Broglie]], [[Marie Curie]], and Einstein.<ref name= SMahanti/><ref name="shanbhag">{{cite web | first = MR | last = Shanbhag | work = Personalities | title = Scientist | url = http://www.calcuttaweb.com/people/snbose.shtml | publisher = Calcutta web | url-status=dead | archive-url = https://web.archive.org/web/20020802081628/http://www.calcuttaweb.com/people/snbose.shtml | archive-date = 2 August 2002 | df = dmy-all }}</ref><ref name = "OConnorRobertson">{{cite web | first1 = JJ | last1 = O'Connor | first2 = EF | last2 = Robertson | date = October 2003 | title = Satyendranath Bose | url = http://www-history.mcs.st-andrews.ac.uk/Biographies/Bose.html | publisher = St Andrew's | work = The MacTutor History of Mathematics archive | place = UK | access-date = 1 February 2012 | archive-date = 18 September 2015 | archive-url = https://web.archive.org/web/20150918212827/http://www-history.mcs.st-andrews.ac.uk/Biographies/Bose.html | url-status = live }}</ref>{{sfn|Wali|2009|pp = xx–xxiii}}

===Bose–Einstein statistics===

While presenting a lecture<ref>{{cite web | first =MR | last =Shanbhag | title =Satyendra Nath Bose (January 1, 1894 – February 4, 1974) | url =http://www.isical.ac.in/~econophys/bose.html | publisher =Indian Statistical Institute | access-date =1 February 2012 | archive-date =28 May 2012 | archive-url =https://web.archive.org/web/20120528020607/http://www.isical.ac.in/~econophys/bose.html | url-status =live }}</ref> at the [[University of Dhaka]] on the theory of [[radiation]] and the [[ultraviolet catastrophe]], Bose intended to show his students that the contemporary theory was inadequate, because it predicted results not in accordance with experimental results.

In the process of describing this discrepancy, Bose 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 {{math|''h''<sup>3</sup>}}, and discarding the distinct position and [[momentum]] of the particles.

Bose adapted this lecture into a short article called "Planck's Law and the Hypothesis of Light Quanta" and sent it to [[Albert Einstein]] with the following letter:<ref>{{Citation |title=Bose And His Statistics | first =G | last = Venkataraman |page=14 | publisher =Universities Press |year=1992 |isbn= 978-81-7371-036-0}}</ref>
{{blockquote|Respected Sir, 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 {{math|8π ν<sup>2</sup>/''c''<sup>3</sup>}} in Planck's Law independent of classical electrodynamics, only assuming that the ultimate elementary region in the phase-space has the content {{math |''h''<sup>3</sup>}}. 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 für 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 on Generalised Relativity.}}

Einstein agreed with him, translated Bose's papers "Planck's Law and Hypothesis of Light Quanta" into German, and had it published in ''[[Zeitschrift für Physik]]'' under Bose's name, in 1924.{{sfn|Wali|2009|p= 414}}
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! Head
| HH || HT
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<div style="thumbcaption">'''(2)''' Since the coins are distinct, there are two outcomes which produce a head and a tail. The probability of two heads is one-quarter.</div>
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The reason Bose's interpretation 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 [[boson]]s, the probability of producing two heads would indeed be one-third (tail-head = head-tail).

Bose's interpretation is now called [[Bose–Einstein statistics]]. This result derived by Bose laid the foundation of [[quantum statistics]], and especially the revolutionary new philosophical conception of the indistinguishability of particles, as acknowledged by Einstein and Dirac.{{sfn|Wali|2009|p= 414}} When Einstein met Bose face-to-face, he asked him whether he had been aware that he had invented a new type of statistics, and he very candidly said that no, he wasn't that familiar with [[Boltzmann]]'s statistics and didn't realize that he was doing the calculations differently. He was equally candid with anyone who asked.
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====Bose–Einstein condensate====
{{Standard model of particle physics|Scientists}}
[[File:Bose Einstein condensate.png|thumb|left|250px|Velocity-distribution data of a gas of [[rubidium]] atoms, confirming the discovery of a new phase of matter, [[Bose–Einstein condensate|the Bose–Einstein condensate]].<ref>{{Citation | contribution-url = http://patapsco.nist.gov/imagegallery/details.cfm?imageid=193 | contribution = Quantum Physics; Bose Einstein condensate | publisher = NIST | title = Image Gallery | date = 11 March 2006 | url = http://patapsco.nist.gov/ | access-date = 12 April 2012 | archive-date = 16 May 2012 | archive-url = https://web.archive.org/web/20120516181854/http://patapsco.nist.gov/ | url-status = live }}.</ref> Left: just before the appearance of a Bose–Einstein condensate. Center: just after the appearance of the condensate. Right: after further evaporation, leaving a sample of nearly pure condensate.]]

Einstein also did not at first realize how radical Bose's departure was, and in his first paper after Bose, he was guided, like Bose, by the fact that the new method gave the right answer. But after Einstein's second paper using Bose's method in which Einstein predicted the Bose-Einstein condensate (''pictured left''), he started to realize just how radical it was, and he compared it to wave/particle duality, saying that some particles didn't behave exactly like particles.  Bose had already submitted his article to the British Journal ''Philosophical Magazine'', which rejected it before he sent it to Einstein. It is not known why it was rejected.<ref>A.Douglas Stone, Chapter 24, ''The Indian Comet'', in the book ''Einstein and the Quantum'', Princeton University Press, Princeton, New Jersey, 2013.</ref>

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 [[boson]]s (which are particles with integer [[Spin (physics)|spin]], named after Bose), which was demonstrated to exist by experiment in 1995.
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===Dhaka===
[[File:Satyendra-nath-bose.jpg|thumb|Bose at Dhaka University in the 1930s]]
After his stay in Europe, Bose returned to [[Dhaka]] in 1926. He did not have a doctorate, and so ordinarily, under the prevailing regulations, he would not be qualified for the post of Professor he applied for, but [[Einstein]] recommended him. He was then made [[Chair (official)|Head]] of the Department of [[Physics]] at [[Dhaka University]]. He continued guiding and teaching at Dhaka University and was the [[Dean (education)|Dean]] of the Faculty of Science there until 1945.

Bose designed equipment himself for an [[X-ray crystallography]] laboratory. He set up laboratories and libraries to make the department a center of research in X-ray spectroscopy, X-ray diffraction, magnetic properties of matter, optical spectroscopy, wireless, and [[Unified field theory|unified field theories]]. He also published an [[equation of state]] for [[real gas]]es with [[Meghnad Saha]].

===Calcutta===
When the [[partition of India]] became imminent (1947), he returned to [[Calcutta]] (now known as Kolkata) and taught there until 1956. He insisted every student design their own equipment using local materials and local technicians. He was made [[Emeritus|professor emeritus]] on his retirement.<ref name="shanbhag"/>{{sfn|Wali|2009|pp = xxx, xxiv}}<ref name=SMahanti/> He then became Vice-Chancellor of [[Visva-Bharati University]] in [[Santiniketan]]. He returned to the University of Calcutta to continue research in nuclear physics and complete earlier works in organic chemistry. In subsequent years, he worked in applied research such as extraction of [[helium]] in hot springs of [[Bakreshwar]].{{sfn|Wali|2009|pp =xxxvi, xxxviii}}

===Other fields===
Apart from physics, he did research in [[biotechnology]] and literature ([[Bengali literature|Bengali]] and English). He made studies in [[chemistry]], geology, [[zoology]], [[anthropology]], engineering and other sciences. Being [[Bengali people|Bengali]], he devoted significant time to promoting [[Bengali language|Bengali]] as a teaching language, translating scientific papers into it, and promoting the development of the region.<ref name="OConnorRobertson"/>{{sfn|Wali|2009|pp =xxiv, xxxix}}<ref name=Biography>{{Citation | title = Science world | url = http://scienceworld.wolfram.com/biography/Bose.html | contribution = Bose, Satyendranath (1894–1974) | type = biography | first = Michel | last = Barran | publisher = Wolfram | access-date = 24 January 2006 | archive-date = 1 August 2018 | archive-url = https://web.archive.org/web/20180801223439/http://scienceworld.wolfram.com/biography/Bose.html | url-status = live }}.</ref>
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