Projective modules over polynomial rings: a constructive approach
β Scribed by S. Barhoumi; H. Lombardi; I. Yengui
- Publisher
- John Wiley and Sons
- Year
- 2009
- Tongue
- English
- Weight
- 138 KB
- Volume
- 282
- Category
- Article
- ISSN
- 0025-584X
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β¦ Synopsis
Abstract
We give a constructive proof of the fact that finitely generated projective modules over a polynomial ring with coefficients in a PrΓΌfer domain R with Krull dimension β€ 1 are extended from R. In particular, we obtain constructively that finitely generated projective R[X~1~, β¦, X~n~ ]βmodules, where R is a Bezout domain with Krull dimension β€ 1, are free. Our proof is essentially based on a dynamical method for decreasing the Krull dimension and a constructive rereading of the original proof given by Maroscia and Brewer & Costa. Moreover, we obtain a simple constructive proof of a result due to Lequain and Simis stating that finitely generated modules over R[X~1~, β¦, X~n~ ], n β₯ 2, are extended from R if and only if this holds for n = 1, where R is an arithmetical ring with finite Krull dimension (Β© 2009 WILEYβVCH Verlag GmbH & Co. KGaA, Weinheim)
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