freddo-or

Cold (having less heat) refers to the condition or subjective perception of having low temperature.

The coldest theoretically possible temperature is absolute zero, also called absolute temperature, which is 0 K on the Kelvin scale, a thermodynamic temperature scale, and −273.15 °C on the Celsius scale. Absolute zero is also 0 R on the Rankine scale, another thermodynamic temperature scale, and −459.67 degrees on the Fahrenheit scale.

Since temperature relates to the thermal energy held by an object or a sample of matter, which is the kinetic energy of the random motion of the particle constituents of matter, an object will contain less thermal energy when it is cold than when it is hot. If it were possible to cool a system to absolute zero, all motion of the particles comprising matter would cease and they would be at complete rest in this classical sense. The object would be described as having zero thermal energy. Microscopically in the description of quantum mechanics, however, matter still has zero-point energy even at absolute zero, because of the uncertainty principle.