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arXiv · 2608.21666

Some non-principal rigid ideals in Gorenstein domains of dimension one

Lars Winther Christensen·Alex Gerko·Srikanth B. Iyengar
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Abstract

We discuss an example of a rigid non-principal ideal in a one dimensional (commutative) Gorenstein domain, which contradicts a conjecture of C. Huneke and R. Wiegand. The construction and its analysis were discovered by Codex, when prompted by one of the authors to verify the conjecture or find a counterexample. A proof of the conjecture, also discovered by Codex, is presented when the ring is equicharacteristic and its embedding dimension is at most three.

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Lars Winther Christensen, Alex Gerko, Srikanth B. Iyengar. 2026-08-21. Some non-principal rigid ideals in Gorenstein domains of dimension one. https://arxiv.org/abs/2608.21666

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