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arXiv · 0904.1540

Homological properties of the perfect and absolute integral closures of Noetherian domains

Mohsen Asgharzadeh
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Abstract

For a Noetherian local domain $R$ let $R^+$ be the absolute integral closure of $R$ and let $R_{\infty}$ be the perfect closure of $R$, when $R$ has prime characteristic. In this paper we investigate the projective dimension of residue rings of certain ideals of $R^+$ and $R_{\infty}$. In particular, we show that any prime ideal of $R_{\infty}$ has a bounded free resolution of countably generated free $R_{\infty}$-modules. Also, we show that the analogue of this result is true for the maximal ideals of $R^+$, when $R$ has residue prime characteristic. We compute global dimensions of $R^+$ and $R_{\infty}$ in some cases. Some applications of these results are given.

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Mohsen Asgharzadeh. 2012-08-25. Homological properties of the perfect and absolute integral closures of Noetherian domains. https://arxiv.org/abs/0904.1540

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