Question: What is dark energy

Jonny Brooks-Bartlett answered on 19 Jun 2015:

No one knows if dark energy is real. At the moment it is a theory that hasn’t been proven.

The reason we made it up is because it looks like the universe is expanding and getting bigger and we don’t understand what could be doing it. So we made up dark energy which is something that acts in the opposite way to gravity and pushes everything apart to explain the fact that the universe is expanding.

As I mentioned we don’t know if it’s real or not but it helps us explain what’s happening in the universe so we’re sticking with this idea for now.