International Temperature Scale of 1990 value may then be converted to, and expressed as, a value on the Fahrenheit scale (e.g. 211.953 °F). ITS–90 does not address the highly specialized equipment and procedures used for measuring temperatures extremely close to absolute zero. For instance, to measure temperatures in the nanokelvin range (billionths of a kelvin), scientists using optical lattice laser equipment to adiabatically cool atoms, turn off the entrapment lasers and simply measure how far the atoms drift over time to measure their temperature. A cesium atom with a velocity of 7 mm/s is equivalent to a temperature of about 700 nK (which was a
Absolute hot Absolute hot Absolute hot is a concept of temperature that postulates the existence of a highest attainable temperature of matter. The concept has been popularized by the television series "Nova". In this article, absolute hot is assumed to be the high end of a temperature scale starting at absolute zero, which is the temperature at which entropy is minimal and classical thermal energy is zero. Contemporary models of physical cosmology postulate that the highest possible temperature is the Planck temperature, which has the value . Above about , particle energies become so large that gravitational forces between them would become