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arXiv · 2107.06759

Wiles defect for modules and criteria for freeness

Sylvain Brochard·Srikanth B. Iyengar·Chandrashekhar B. Khare
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Abstract

F. Diamond proved a numerical criterion for modules over local rings to be free modules over complete intersection rings. We formulate a refinement of these results using the notion of Wiles defect. A key step in the proof is a formula that expresses the Wiles defect of a module in terms of the Wiles defect of the underlying ring.

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Sylvain Brochard, Srikanth B. Iyengar, Chandrashekhar B. Khare. 2021-07-14. Wiles defect for modules and criteria for freeness. https://arxiv.org/abs/2107.06759

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