AARP15
From Exampleproblems
Prove that the center of a division ring is a field.
A field is a commutative division ring and the center is commutative by definition. The problem is reduced to showing that the center of a division ring is also a division ring. A division ring contains multiplicative inverses for all nonzero elements, so it only has to be shown that
.
If
, then
so
.
