absolute zero

temperature at which it is believed that all molecular activity ceases (-273.16 degrees Celsius/-459.69 degrees Fahrenheit)

Absolute zero describes a theoretical system that neither emits nor absorbs energy. The Absolute zero temperature is known to be (–273.15 °C). It is the point at which particles have a minimum energy, determined by quantum mechanical effects, which is called the zero-point energy. By international agreement, absolute zero is defined as precisely on the Kelvin scale, which is a thermodynamic (absolute) temperature scale, and –273.15 °C on the Celsius scale. Absolute zero is also precisely equivalent to 0 °R on the Rankine scale (also a thermodynamic temperature scale), and –459.67 °F on the Fahrenheit scale.
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Noun
1. (cryogenics) the lowest temperature theoretically attainable (at which the kinetic energy of atoms and molecules is minimal); 0 Kelvin or -273.15 Centigrade or -459.67 Fahrenheit
(hypernym) temperature
(classification) cryogenics, cryogeny

Theorised to be the lowest temperature it is possible to attain. As matter is cooled down, so the motion of atoms and molecules gradually ceases. At absolute zero all movement stops. It occurs at -273 degrees on the centigrade scale and defines the zero degrees point on the Kelvintemperature scale.

The temperature at which the volume of an ideal gas becomes zero; a theoretical coldest temperature that can be approached but never reached. Absolute zero is zero on the Kelvin scale, -273.15°C on the Celsius scale, and -459.67°F on the Fahrenheit scale.