Some properties of projective modules over discrete Hodge algebras
โ Scribed by Andreas Wiemers
- Publisher
- Elsevier Science
- Year
- 1992
- Tongue
- English
- Weight
- 747 KB
- Volume
- 150
- Category
- Article
- ISSN
- 0021-8693
No coin nor oath required. For personal study only.
โฆ Synopsis
All rings in this paper are assumed to be commutative with 1 and all modules finitely generated.
Let B be a discrete Hodge algebra over a.ring A. By definition this means that B=R/I where R=A[XI ..... X,,] and I is an ideal in R generated by monomials. T. Vorst showed in 1-12] that thebehavior of projective modules over such B is very similar to the case of an ordinary polynomial ring in the following sense: If all projective modules over any polynomial ring with ground ring A are, extended from A, then every projective module over a discrete Hodge algebra over A is extended from A.
Let B be a discrete Hodge algebra over a Noetherian ring A and P a projective module over B. S. Mandal proved in [7] that if rank P~> dim B/> dim A + 1 then (i) P has the cancellation property, i.e., for every B-module Q B(DP~_B@Q implies P~Q.
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