Dark Energy

In physical cosmology and astronomy, dark energy is a proposed form of energy that affects the universe on the largest scales. Its primary effect is to drive the accelerating expansion of the universe. It also slows the rate of structure formation.[1] Assuming that the lambda-CDM model of cosmology is correct,[2] dark energy dominates the universe, contributing 68% of the total energy in the present-day observable universe.

The exact nature of dark energy remains a mystery, and many possible explanations have been theorized. The main candidates are a cosmological constant[12][13] (representing a constant energy density filling space homogeneously) and scalar fields (dynamic quantities having energy densities that vary in time and space) such as quintessence or moduli.