The characteristic pp André–Oort conjecture for products of GSpin Shimura varieties

Let f:X0SI,Fordf:X_0\to\mathscr{S}_{\mathbf{I},F_{\infty}}^{\operatorname{ord}} be a locally closed immersion, and let XX be its image. Suppose that XX possesses a Zariski-dense collection \A\A of positive-dimensional special subvarieties. Define \I\A\I_{\A} to be the set of indices whose projections contain a Zariski-dense collection of special subvarieties with positive-dimensional projections. For indices in \I\A\I_{\A}, let XiX_i be the corresponding projections, and decompose their Shimura data into simple adjoint factors indexed by \J\J; let \J\A\J_{\A} record the factors with positive-dimensional projected special subvarieties. The characteristic pp André–Oort conjecture for products of GSpin Shimura varieties. The variety XX is quasi-weakly special; if #I=1\#\mathbf{I}=1, it is special. More precisely: (1) each XiX_i for iIAi\in\mathbf{I}_{\mathbf{A}} is special; (2) XX is the product of a quasi-weakly special subvariety YSIA,FY\subseteq\mathscr{S}_{\mathbf{I}_{\mathbf{A}},F_{\infty}} with a subvariety of SIIA,F\mathscr{S}_{\mathbf{I}-\mathbf{I}_{\mathbf{A}},F_{\infty}}; and (3) YY is an almost product of a special subvariety of jJAYj,Ford\prod_{j\in\mathbf{J}_{\mathbf{A}}}\mathscr{Y}_{j,F_{\infty}}^{\operatorname{ord}} with a subvariety of jJJAYj,Ford\prod_{j\in\mathbf{J}-\mathbf{J}_{\mathbf{A}}}\mathscr{Y}_{j,F_{\infty}}^{\operatorname{ord}}. In particular, if each XiX_i is simple, then YY is special.

This is the product form of the characteristic-pp André–Oort prediction, refining quasi-weak specialness by an almost-product description. The supplied passage does not give a resolution status.

Sources & referencesView supporting material

Primary source

Ruofan Jiang, “p-adic monodromy and mod p unlikely intersections, I”, arXiv:2308.06854 (2025).

Progress summary

Never refreshed

Nothing recorded yet. Refresh searches the literature and the public web for attempts on this problem, and writes the first summary here.

Solutions 0

No solutions have been posted yet.