Theory of everything
| The facts of the matter|
|May the mass times acceleration be with you|
|Let's get physical!|
|Atoms trying to understand atoms|
A theory of everything (or the Unified Field Theory) describes the gravitational, the weak nuclear, the strong nuclear and the electromagnetic forces in a single unifying framework. As things now stand, general relativity offers the best description of gravitational interactions while quantum mechanics addresses the remaining ones in the so-called Standard Model of particle physics. (Note that the Standard Model has already taken into account special relativity.) Hence, formulating a theory of everything is synonymous with unifying general relativity with quantum mechanics. Such a theory would explain everything, at least in principle. For a certain value of "everything", at least; more precisely, it would explain everything about fundamental physics. Such a "theory of everything" differs from the so-called "Grand Unified Theories", which exist but do not include gravity and do not agree with experimental data.
- See A Brief History of Time by Stephen Hawking. Ch 10.