Constancy of Hodge-goodness at the boundary case n=p

Determine whether Hodge-goodness remains constant in smooth proper families of relative dimension $2n$ when $n=p$, under the family hypotheses used in the paper.

Background

The paper proves constancy of Hodge-goodness under relative W2W_2-liftings when n<pn<p. The proof uses low-degree Deligne–Illusie decompositions and a cup product from degrees below pp.

At the boundary case n=pn=p, the coherent cohomology dimensions remain constant, but the cup product from degree p−1p-1 to degree p+1p+1 lies outside the range controlled by the argument. The authors therefore leave unresolved whether Hodge-goodness is nevertheless constant.

References

We do not know whether Hodge-goodness remains constant there, or whether eq:ct2 can be removed from the family theorem.

eq:ct2:

$b\longmapsto\dim_{\kappa(b)}\HH^2(Y_b,T_{Y_b}) \tag{$\textup{ct}_2$} $

— Quasi-$F$-split primitive symplectic varieties in positive characteristic  (2609.35467 - Zou, 28 Sep 2026) in Remark 5.12, Section 5.4, “The dichotomy on the whole base”