General relativity is unquestionably Einstein's masterpiece, a theory which reveals the workings of the universe at the grandest scales, capturing in one beautiful line of algebra everything from why apples fall from trees to the beginning of time and space.
the universe is far, far too interesting. Relativity and quantum mechanics appear to suggest that the universe should be a boring place. It should be dark, lethal and lifeless. But when we look around us, we see we live in a universe full of interesting stuff.
One of the most important consequences of Einstein's general theory of relativity was the discovery that the universe began as a rapid expansion.