Cold refers to the condition or subjective perception of having low temperature, the opposite of hot.
A lower bound to temperature is the absolute zero, defined as 0 K on the Kelvin scale, an absolute thermodynamic temperature scale. This corresponds to −273.15 °C on the Celsius scale, −459.67 °F on the Fahrenheit scale, and 0 °R on the Rankine 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 have less thermal energy when it is colder and more when it is hotter. If it were possible to cool a system to absolute zero, all motion of the particles in a sample of 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.
Famous quotes containing the word cold:
“It had been cold since December. Snow fell, first,
At New Year and, from then until April, lay
On everything. Now it had melted, leaving
The gray grass like a pallet, closely pressed;
And dirt. The wind blew in the empty place.”
—Wallace Stevens (18791955)
“All observations point to the fact that the intellectual woman is masculinized; in her, warm, intuitive knowledge has yielded to cold unproductive thinking.”
—Helene Deutsch (18841982)
“Opinionated writing is always the most difficult ... simply because it involves retaining in the cold morning-after crystal of the printed word the burning flow of molten feeling.”
—Gavin Lyall (b. 1932)