![cover image](https://wikiwandv2-19431.kxcdn.com/_next/image?url=https://upload.wikimedia.org/wikipedia/commons/thumb/e/ee/Divergence_%2528captions%2529.svg/640px-Divergence_%2528captions%2529.svg.png&w=640&q=50)
Divergence
Vector operator in vector calculus / From Wikipedia, the free encyclopedia
In vector calculus, divergence is a vector operator that operates on a vector field, producing a scalar field giving the quantity of the vector field's source at each point. More technically, the divergence represents the volume density of the outward flux of a vector field from an infinitesimal volume around a given point.
![A vector field with diverging vectors, a vector field with converging vectors, and a vector field with parallel vectors that neither diverge nor converge](http://upload.wikimedia.org/wikipedia/commons/thumb/e/ee/Divergence_%28captions%29.svg/320px-Divergence_%28captions%29.svg.png)
As an example, consider air as it is heated or cooled. The velocity of the air at each point defines a vector field. While air is heated in a region, it expands in all directions, and thus the velocity field points outward from that region. The divergence of the velocity field in that region would thus have a positive value. While the air is cooled and thus contracting, the divergence of the velocity has a negative value.