Dark energy and gravity. Astronomers think that the expansion of the universe is regulated both by the force of gravity, which acts to slow it down, and a mysterious dark energy, which pushes matter and space apart. Dark energy is thought to be pushing the cosmos apart at faster and faster speeds, causing our universe's expansion to accelerate. Here, dark energy is represented by the purple grid (top) and gravity by the green grid (bottom). Gravity emanates from all matter in the universe, but its effects are localised and drop off quickly over large distances. New research confirms that dark energy is a smooth uniform force that now dominates over the effects of gravity. These observations follow careful measurements of the separations between pairs of