Quotient condition for bounded-codimension complete intersections

Determine whether the property of being a complete intersection of codimension at most c satisfies the quotient condition for every integer c≥1.

Background

The paper studies the property CIc\mathsf{CI}_{\leq c} of Noetherian local rings that are complete intersections whose codimension is at most cc. The quotient condition (QC) requires that, whenever a Noetherian ring satisfies the property at all of its localizations, the corresponding property-locus in every prime quotient contains a nonempty open subset.

The paper proves that CIc\mathsf{CI}_{\leq c} does not satisfy the Nagata criterion (NC) for any c1c\geq 1, while it establishes stability under localization and suitable regular-sequence reductions and proves openness of the CIc\mathsf{CI}_{\leq c}-locus for rings satisfying Reg\mathsf{Reg}-Q0. The status of the quotient condition for these bounded-codimension complete-intersection classes is left unresolved.

References

Does $\mathsf{CI}_{\leq c}$ satisfy (QC) in general for any $c \geq 1$?

Complete Intersections of Bounded Codimension: Failure of the Nagata Criterion and Recovery of Openness  (2608.18835 - Ikeda, 19 Aug 2026) in Question 1, Section 6, “Open questions,” label q:QC_cifin