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Bose-Einstein condensate, a gas of atoms that has been so chilled that their motion is virtually halted and as a consequence they lose their separate identities and merge into a single entity. The condensate was predicted by Albert Einstein in 1924 based on the system of quantum statistics formulated by the Indian mathematician Satyendra Nath Bose. Quantum theory asserts that atoms and other elementary particles can be thought of as waves. Einstein proposed that as atoms approach absolute zero (-273.15°C), the waves expand in inverse proportion to their momentum until they fall into the same quantum state and finally overlap, essentially behaving like a single atom. The phenomenon could not be observed, however, until techniques were developed to reduce temperatures to within 20 billionths of a degree above absolute zero. In 1995 Eric A. Cornell and Carl E. Wieman led a team that isolated a rubidium Bose-Einstein condensate under laboratory conditions. It is believed that this state of matter could never have existed naturally anywhere in the universe, since the low temperatures required for its existence cannot be found, even in outer space. The condensate may be useful in the study of superconductivity (the ability of some materials to conduct electrical current without any resistance) and superfluidity (the ability of some materials to flow without resistance) and in refining measurements of time and distance.
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