Dark energy, popularly known as the “fifth force” is an unknown form of energy which is hypothesized to permeate all of space, tending to accelerate the expansion of the universe.
It is the most accepted hypothesis to explain the observations since the 1990s indicating that the universe is expanding at an accelerating
Like gravity, dark energy influences all matter in the galaxy, and its effects can be seen on both cosmological and subatomic scales. The repulsive effects of dark energy are the primary reason the expansion of the universe is gradually accelerating
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