Imagine that it turns out that dark matter (not dark energy)is made up of an unstable form of matter that decays into photons or other forms of energy about 50 billion years from now.Based on current understanding,how would that affect the universe at that time?

Question

Quizplus · Accepted Answer

Dark matter provides the gravitational glue that holds galaxies together in clusters. If it were to decay into forms of energy like photons, the gravitational binding would weaken, causing galaxies within clusters to begin to fly apart due to the lack of sufficient gravitational pull to keep them together.

Imagine That It Turns Out That Dark Matter (Not Dark