TY - JOUR

T1 - Integrality for PI-rings

AU - Braun, Amiram

AU - Vonessen, Nikolaus

N1 - Funding Information:
*This work was done while the first author enjoyedt he hospitalityo f the universityo f Southern California, Los Angeles. + Partially supported by NSF Grant DMS 8901491.

PY - 1992/9

Y1 - 1992/9

N2 - In this paper, we study (Schelter) integral extensions of PI-rings. We prove in particular lying over, going up, and incomparability for prime ideals. A major result is transitivity of integrality: If R⊆S⊆B are PI-rings such that B is integral over S and S is integral over R, then B is integral over R. Next, we obtain a powerful criterion for integrality: If S is a prime PI-ring such that its center is integral over a Noetherian subring R of S, then S is integral over R. This allows interesting applications to the theory of finite group actions. Further topics concern Eakin-Nagata type results and embeddings of quotient rings for integral extensions. Finally, we analyze the relationship between module-finite extensions and finitely generated integral extensions, obtaining positive results for affine Noetherian PI-algebras and algebras satisfying certain restrictions on PI-degrees (e.g., algebras of low PI-degree).

AB - In this paper, we study (Schelter) integral extensions of PI-rings. We prove in particular lying over, going up, and incomparability for prime ideals. A major result is transitivity of integrality: If R⊆S⊆B are PI-rings such that B is integral over S and S is integral over R, then B is integral over R. Next, we obtain a powerful criterion for integrality: If S is a prime PI-ring such that its center is integral over a Noetherian subring R of S, then S is integral over R. This allows interesting applications to the theory of finite group actions. Further topics concern Eakin-Nagata type results and embeddings of quotient rings for integral extensions. Finally, we analyze the relationship between module-finite extensions and finitely generated integral extensions, obtaining positive results for affine Noetherian PI-algebras and algebras satisfying certain restrictions on PI-degrees (e.g., algebras of low PI-degree).

UR - http://www.scopus.com/inward/record.url?scp=38249009047&partnerID=8YFLogxK

U2 - 10.1016/0021-8693(92)90131-5

DO - 10.1016/0021-8693(92)90131-5

M3 - Review article

AN - SCOPUS:38249009047

SN - 0021-8693

VL - 151

SP - 39

EP - 79

JO - Journal of Algebra

JF - Journal of Algebra

IS - 1

ER -