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arXiv · 1801.02491

On Carlson's Depth Conjecture

James A. Schafer
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Abstract

J.F. Carlson conjectured in 1995 that if G is a finite group and k is a field whose characteristic p divides the order of G that the depth of H*(G,k) equals the minimum of the dimensions of associated primes of H*(G,k). This is obviously true if H*(G,k) is Cohen-Macaulay and definitely false for arbitrary finitely generated k-algebras. It was shown by Carlson to be true if the dimension of H*(G,k) equals 2 and by D.J. Green to be true if the depth of H*(G,k) is equal to its possible minimum value, namely the maximum of the dimensions of elementary abelian p-groups contained in the center of G. In this paper we show the conjecture is true if dimension(H*(G,k))-depth(H*(G,k))=1. Known examples show the conjecture to be false for arbitrary finitely generated k-algebras satisfying this condition.

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James A. Schafer. 2018-01-08. On Carlson's Depth Conjecture. https://arxiv.org/abs/1801.02491

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