# Theory of relativity

The **theory of relativity** usually encompasses two interrelated theories by Albert Einstein: /special relativity and /general relativity. Special relativity applies to elementary particles and their interactions, describing all their physical phenomena except gravity. General relativity explains the law of gravitation and its relation to other forces of nature. It applies to the cosmological and astrophysical realm, including astronomy.^{[1]}

## ResourcesEdit

- Equivalence principle
- Fictitious force
- Friedmann–Lemaître–Robertson–Walker metric
- General relativity
- General relativity/Einstein equations
- General relativity/Introduction
- Kerr–Newman metric
- Linearized general relativity
- Reissner-Nordström
- Rindler coordinates
- Schwarzschild metric
- Special relativity
- Special relativity/E = mc²
- Special relativity/energy
- Special relativity/momentum
- Special relativity/space, time, and the Lorentz transform
- Special relativity/spacetime diagrams and vectors