dark energydark energy
energy whose existence is postulated by astrophysicists to account for the perceived acceleration of the expansion of the universe
A hypothetical form of energy that permeates all space and tends to cause the universe to expand by exerting a gravitational repulsion, countering ordinary gravitational attraction. Two forms of dark energy are quintessence and the vacuum energy represented by the cosmological constant.
- (astronomy, astrophysics) A hypothetical form of energy which, it is supposed, is spread uniformly throughout space (time) and has anti-gravitational properties: it represents a possible mechanism for the cosmological constant, and thus is one of the possible explanations for the current accelerating rate of expansion of the universe; and it is estimated to account for about 74% of the mass-energy of the universe.