Temperature at which a thermodynamic system (see thermodynamics) has the lowest energy, 0 kelvin (K). It corresponds to −459.67°F (−273.15°C) and is the lowest possible temperature theoretically achievable by a system. A gas at constant pressure contracts as the temperature is decreased. A perfect gas would reach zero volume at absolute zero. However, a real gas condenses to a liquid or a solid at a temperature higher than absolute zero. At absolute zero, the system's molecular energy is minimal and none is available for transfer to other systems. The Kelvin temperature scale has absolute zero as its zero point, and its fundamental unit is the kelvin.
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Political doctrine and practice of unlimited, centralized authority and absolute sovereignty, especially as vested in a monarch. Its essence is that the ruling power is not subject to regular challenge or check by any judicial, legislative, religious, economic, or electoral agency. Though it has been used throughout history, the form that developed in early modern Europe (16th–18th century) became the prototype; Louis XIV is seen as the epitome of European absolutism. Religious authority was assumed by the monarch, who became the head of the church as well as the state, on the basis that the right to rule came from God (see divine kingship). Seealso authoritarianism, dictatorship, totalitarianism.
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Math and science