Władysław Natanson was a Polish

Poland

Poland , officially the Republic of Poland , is a country in Central Europe bordered by Germany to the west; the Czech Republic and Slovakia to the south; Ukraine, Belarus and Lithuania to the east; and the Baltic Sea and Kaliningrad Oblast, a Russian exclave, to the north...

 physicist

Physicist

A physicist is a scientist who studies or practices physics. Physicists study a wide range of physical phenomena in many branches of physics spanning all length scales: from sub-atomic particles of which all ordinary matter is made to the behavior of the material Universe as a whole...

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He was head of Theoretical Physics at Jagiellonian University

Jagiellonian University

The Jagiellonian University was established in 1364 by Casimir III the Great in Kazimierz . It is the oldest university in Poland, the second oldest university in Central Europe and one of the oldest universities in the world....

 from 1899–1935. He published a series of papers on the problems of thermodynamically irreversible processes, gaining him recognition in the rapidly-growing field. He was the first to take into accout the distinguishability of photons in the statistical analysis of elementary processes, being a precursor of the notion of quantum indistinguishability

Identical particles

Identical particles, or indistinguishable particles, are particles that cannot be distinguished from one another, even in principle. Species of identical particles include elementary particles such as electrons, and, with some clauses, composite particles such as atoms and molecules.There are two...

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