When the Duke scientists say "ultra-cool" they mean uber-cooled to around 150 micro-Kelvin — that's only a few billionths of a degree Kelvin above absolute zero.

杜克的科学家们所说的“超冷”意指超级冷却到150微开尔文左右——这仅仅比绝对零度高几亿分之一开尔文。

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Absolute zero is unattainable, but temperatures within one millionth of a degree have been reached.

绝对零度是不能达到的，但科学家已经实现了百万分之一度的温度。

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This slows down the movement, and hence the temperature, of its atoms to a fraction of a degree above absolute zero.

ECONOMIST: An old thought experiment may soon be realised

Dr Cornell and Dr Wieman had to plumb the icy depths of 20 billionths of a degree above absolute zero in order to win their prize.

ECONOMIST: The 2001 Nobel prizes: Playing catch-up | The

These atoms are cooled to a temperature of only a few billionths of a degree above absolute zero, the coldest possible temperature, at which all motion stops.

BBC: A Bose-Einstein condensate: It slows down light