In this paper we investigate the relationship between simplicial and crossed resolutions of commutative algebras.
Free Resolutions of Simplicial Posets
β Scribed by Art M Duval
- Publisher
- Elsevier Science
- Year
- 1997
- Tongue
- English
- Weight
- 371 KB
- Volume
- 188
- Category
- Article
- ISSN
- 0021-8693
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β¦ Synopsis
A simplicial poset, a poset with a minimal element and whose every interval is a Boolean algebra, is a generalization of a simplicial complex. Stanley defined a ring A associated with a simplicial poset P that generalizes the face-ring of a P w x simplicial complex. If V is the set of vertices of P, then A is a k V -module; we P find the Betti polynomials of a free resolution of A , and the local cohomology P modules of A , generalizing Hochster's corresponding results for simplicial com-P plexes. The proofs involve splitting certain chain or cochain complexes more finely than in the simplicial complex case. Corollaries are that the depth of A is a P topological invariant, and that the depth may be computed in terms of the Cohen-Macaulayness of skeleta of P, generalizing results of Munkres and Hibi.
π SIMILAR VOLUMES
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