theory of everything

Albert Einstein made many great contributions to science that include the Special Theory of Relativity and the General Theory of Relativity. But one of his theories -- the "theory of everything" -- was never completed. Einstein hoped that this equation, also called a "unified theory," would explain how everything in the Universe works. That's why we call it the theory of everything.

theory of everything
What it is: a simple, yet complete, theory that explains how everything in the Universe works
First introduced by: Albert Einstein
Also called: unified theory
What it would encompass: theories of the physical world on the largest level and on the most microscopic level
Current models: string theories, super symmetry, and membrane theory

Image credits: main image: Eric Hamilton.