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arXiv · 1407.0472

Cohomologically complete intersections with vanishing of Betti numbers

Waqas Mahmood
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Abstract

Let $I$ be ideal of an $n$-dimensional local Gorenstein ring $R$. In this paper we will describe several necessary and sufficient conditions such that the ideal $I$ becomes cohomologically complete intersections. In fact, as a technical tool, it will be shown that the vanishing $H^i_{I}(R)= 0$ for all $i\neq c= \grade (I)$ is equivalent to the vanishing of the Betti numbers of $H^c_{I}(R)$. This gives a new characterization to check the cohomologically complete intersections property with the homological properties of the vanishing of Tor modules of $H^c_{I}(R)$.

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Waqas Mahmood. 2014-07-02. Cohomologically complete intersections with vanishing of Betti numbers. https://arxiv.org/abs/1407.0472

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