Absolute zero is defined as the lowest temperature possible on the Kelvin scale, but in early 2013, scientists were able to create an atomic gas in a laboratory that actually reached sub-absolute zero temperatures. This temperature is equivalent to -459.67° Fahrenheit (-273.15° Celsius). Physicists in Germany cooled quantum gas in a chamber and used magnetic fields and lasers to rearrange its atomic particles. At positive temperatures on the Kelvin scale, atoms attract each other and remain stable, but with these changes to the atomic arrangements, the particles repelled each other and thus were theoretically considered to be at a negative temperature on the Kelvin scale.
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