Action at a distance consists of affecting a distant body instantaneously. At the atom level, this is known as "non-locality".
Examples of action at a distance in physics are:
- Newtonian gravity
- Electrostatics (before Maxwell's equations in the 1800s)
- Some interpretations of quantum entanglement within quantum mechanics (called "non-locality")
Some scientists have long resisted the possibility of action at at distance (non-locality), and the theory of relativity suggests that information traveling instantaneously, or faster than the speed of light, may be impossible.
Several theories have been developed as ways of denying action at a distance (non-locality). These include:
- string theory
- quantum field theory