# What Is The Theory Of Relativity Used For?

In his theory of special relativity, Albert Einstein determined that the laws of physics are the same for all non-accelerating observers, and he showed that the speed of light within a vacuum is the same no matter the speed at which an observer travels.

The theory explains the behaviour of objects in space and time, and it can be used to predict everything. For example:

• The existence of black holes
• Light bending due to gravity
• The behaviour of the planet Mercury in its orbit