Noetherian algebras over algebraically closed fields

Abstract

Let $k$ be an uncountable algebraically closed field and let $A$ be a countably generated left Noetherian $k$-algebra. Then we show that $A{\otimes }_{k}K$ is left Noetherian for any field extension $K$ of $k$. We conclude that all subfields of the quotient division algebra of a countably generated left Noetherian domain over $k$ are finitely generated extensions of $k$. We give examples which show that $A{\otimes }_{k}K$ need not remain left Noetherian if the hypotheses are weakened.

10 pages