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Bose was born in Kolkata (Calcutta), the eldest of seven children. His father, Surendranath Bose, worked in the Engineering Department of the East India Railway . Bose attended Hindu High School in Calcutta, and later attended Presidency College, also in Calcutta, always earning the highest marks. From 1916 to 1921 he was a lecturer in the physics department of Calcutta University. In 1921, he joined the physics department of the then recently founded University of Dhaka, again as a lecturer. In 1926 he became a professor and was made head of the physics department, and continued teaching at Dacca University until 1945. At that time he returned to Calcutta, and taught at Calcutta University until 1956, when he retired and was made professor emeritus.
| Two heads | Two tails | One of each |
There are three outcomes. What is the probability of producing two heads?
While at Dacca University, Bose wrote a short article called Planck's Law and the Hypothesis of Light Quanta, describing the photoelectric effect and based on a lecture he had given on the ultraviolet catastrophe. During this lecture, in which he had intended to show his students that theory predicted results not in accordance with experimental results, Bose made an embarrassing statistical error which gave a prediction that agreed with observations, a contradiction.
| Coin 1 | |||
|---|---|---|---|
| Head | Tail | ||
| Coin 2 | Head | HH | HT |
| Tail | TH | TT | |
Since the coins are distinct, there are two outcomes which produce a head and a tail. The probability of two heads is one-fourth.
The error was a simple mistake that would appear obviously wrong to anyone with a basic understanding of statistics, and similar to arguing that flipping two fair coins will produce two heads one-third of the time. However, it produced correct results, and Bose realized it might not be a mistake at all.
Physics journal s refused to publish Bose's paper. It was their contention that he had presented to them a simple mistake, and Bose's findings were ignored. Discouraged, he wrote to Albert Einstein, who immediately agreed with him. Physicists stopped laughing when Einstein sent Zeitschrift für Physik his own paper to accompany Bose's.Because photons are indistinguishable from each other, one cannot treat any two photons having equal energy as being different from each other. By analogy, if the coins in the above example behaved like photons and other bosons, the probability of producing two heads would indeed be one-third. Bose's "error" is now called Bose-Einstein statisticsIn statistical thermodynamics, Bose-Einstein statistics determines the statistical distribution of identical indistinguishable bosons over the energy states in thermal equilibrium. Bose-Einstein (or B-E statistics are closely related to Maxwell-Boltzmann.
Einstein adopted the idea and extended it to atoms. From this, he predicted the existence of phenomena which became known as Bose-Einstein condensateA Bose-Einstein condensate is a gaseous superfluid phase formed by atoms cooled to temperatures very near to absolute zero. The first such condensate was produced by Eric Cornell and Carl Wieman in 1995, using a gas of rubidium atoms cooled to one twenty-, a dense collection of bosons (which are particles with integer spinIn physics, spin is an intrinsic angular momentum associated with microscopic particles. It is a purely quantum mechanical phenomenon without any analogy in classical mechanics. Whereas classical angular momentum arises from the rotation of an extended ob, named after Bose).