How can the universe be speeding up in its expansion? Since gravity is the only force that controls wouldn’t the universe ultimately always contract again over time because gravity would eventually win out over the initial acceleration caused by the big bang?

Question

How can the universe be speeding up in its expansion? Since gravity is the only force that controls wouldn’t the universe ultimately always contract again over time because gravity would eventually win out over the initial acceleration caused by the big bang?

In: Physics

Answer 1

1. Gravity is not the only controlling force.
2. The universe is not just expanding, but the expansion is accelerating. Meaning, some thing is causing the expansion and that something is overpowering the gravity. Scientists call this dark energy and it’s characteristics are unknown.