Log resolution conjecture for schemes in the relevant birational class

Establish that every log pair whose underlying scheme is birational to a normal integral scheme quasi-projective over an excellent ring of finite Krull dimension, admitting a dualizing complex and having no residue characteristics equal to 2, 3, or 5, admits a log resolution obtained by a sequence of regular blowups along the non-simple normal crossing locus at each stage.

Background

The paper’s four-dimensional cone theorem is conditional on a log-resolution hypothesis. The required hypothesis concerns a normal integral scheme X over an excellent base with the stated finiteness and residue-characteristic conditions, and all log pairs birational to X. A positive resolution of this conjecture would remove the principal resolution-of-singularities assumption used in the four-dimensional relative minimal model program and consequently in the cone theorem proved here.

References

Conjecture 2.6. Let X be a normal integral scheme quasi-projective over an excellent ring, which is of finite Krull dimension, admits a dualizing complex with no residue characteristic 2, 3 or 5. The log resolution conjecture holds for X if every log pair (Y, ∆Y ) whose underlying scheme Y is birational to X admits a log resolution obtained by a sequence of regular blowups along the non-simple normal crossing locus at each stage.

The cone theorem for effective fourfold pairs in characteristic $p>5$  (2608.14236 - Waldron, 14 Aug 2026) in Conjecture 2.6, Section 2.2.1, p. 4

Our geometric approach via Bertini theorems bypasses this machinery and allows us to work with significantly more general models. Assuming only that the model X is projective, we impose no regularity conditions on it and allow XK to be merely geometrically normal—advantages particularly relevant in dimensions greater than three, where resolution of singularities remains open for models in mixed characteristic and varieties in positive characteristic, respectively.

Semi-abelian reduction of Albanese varieties  (2608.14417 - Chung, 14 Aug 2026) in Section 1.4, page 7