When we do math to calculate things like how fast galaxies are spinning or moving away from each other, we get an impossible number. That means either all our physics laws are wrong, or there is something we don’t know about making them move. We gave this “something” the name dark energy as a placeholder.
The calculated rate at which the universe should expand based on what we know about it and the observed rate at which it actually does expand don’t line up. This discrepancy is attributed to dark matter and dark energy. We don’t actually know what it is, hence the name dark matter/energy, but we do know that there are some factors that are unaccounted for in the expansion of the universe.
Latest Answers