Pushouts of affine algebraic sets

Abstract

We study the problem of existence of pushouts in the category of algebraic sets over an infinite field. This problem can be reduced to asking whether the property of being a finitely generated algebra over a field, or a Noetherian ring in general, is preserved under taking pullbacks. We show that this problem can be fully solved in terms of preservation of this property under taking intersections. In addition, we also discuss specific cases of pushouts of algebraic sets and intersections of Noetherian rings.