# Power law

In

physics, a

**power law** relationship between two

scalar quantities

*x* and

*y* is any such that the relationship can be written as

*y = ax*^{k}

where

*a* (the constant of proportionality) and

*k* (the

exponent of the power law) are constants.

Examples of power law relationships:

Examples of power law

probability distributions:

Power laws are among the most frequent scaling laws that describe the

scaling invariance found in many natural phenomena.