Commutator (ring)

In a ring, the commutator of two elements $a$ and $b$, denoted $[a,b]$, is the quantity $ab-ba$. It can be seen as a measure of the failure of the ring to be commutative; in a commutative ring, $[a,b]=0$. The same definition applies for fields.

This article is a stub. Help us out by expanding it.

See also