Partially supported by the research funds of Ministero dell'Uni¨ersita e della Ricerca Scientifica e Tecnologica and by Grant 9300856.CT01 of Consiglio Nazionale delle Ricerche.
On the class group of a pullback
✍ Scribed by Saı̈d El Baghdadi
- Publisher
- Elsevier Science
- Year
- 2002
- Tongue
- English
- Weight
- 135 KB
- Volume
- 169
- Category
- Article
- ISSN
- 0022-4049
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✦ Synopsis
Let T be an integral domain, I a nonzero proper ideal of T , and ' : T → T=I the natural projection. For an integral domain D which is a proper subring of T=I , R = ' -1 (D) is then a subring of T . We investigate the class group Cl(R), the Picard group Pic(R), and the local class group G(R) of the pullback R.
📜 SIMILAR VOLUMES
This paper studies the class group of a graded integral domain R = ∈ R . We prove that if the extension R0 ⊂ R is inert, then Cl(R) = HCl(R) if and only if R is almost normal. As an application, we state a decomposition theorem for class groups of semigroup rings, namely, Cl(A[ ]) ∼ = Cl(A) ⊕ HCl(K[