An artist’s impression of gravitational waves generated by binary neutron stars. Credit: R. Hurt/Caltech-JPL
Gravity is affected by dark matter and dark energy in opposite ways: dark matter strengthens gravity by adding invisible mass that increases gravitational pull, helping hold galaxies and galaxy clusters together, while dark energy weakens gravity’s influence on large scales by creating a repulsive effect that drives the accelerated expansion of the universe. Inside galaxies, dark matter’s added gravity dominates, keeping structures intact, but across vast cosmic distances, dark energy overpowers gravity and pushes galaxies farther apart.
