This article is a non-technical introduction to the subject. For the main encyclopedia article, see General relativity.

General relativity

 is a theory of gravitation developed by Albert Einstein between 1907 and 1915. The theory of general relativity says that the observed gravitational effect between masses results from their warping of spacetime.

By the beginning of the 20th century, Newtons law of universal gravitation had been accepted for more than two hundred years as a valid description of the gravitational force between masses. In Newtons model, gravity is the result of an attractive force between massive objects. Although even Newton was troubled by the unknown nature of that force, the basic framework was extremely successful at describing motion.