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Tight Closure of Finite Length Modules in Graded Rings

Geoffrey D. Dietz
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Abstract

We look at how the equivalence of tight closure and plus closure (or Frobenius closure) in the homogeneous m-coprimary case implies the same closure equivalence in the non-homogeneous m-coprimary case in standard graded rings. Although our result does not depend upon dimension, the primary application is based on results known in dimension 2 due to the recent results of H. Brenner. We also show that unlike the Noetherian case, the injective hull of the residue field over $R^+$ or $R^\infty$ contains elements that are not killed by any power of the maximal ideal of R.

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Geoffrey D. Dietz. 2007-01-11. Tight Closure of Finite Length Modules in Graded Rings. https://arxiv.org/abs/math/0508357

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