Rectifiability of flat singular points for area-minimizing mod$(2Q)$ hypercurrents

Abstract: Consider an $m$-dimensional area minimizing mod$(2Q)$ current $T$, with $Q\in\mathbb{N}$, inside a sufficiently regular Riemannian manifold of dimension $m + 1$. We show that the set of singular density-$Q$ points with a flat tangent cone is countably $(m-2)$-rectifiable and has locally finite $(m-2)$-dimensional upper Minkowski content. This complements the thorough structural analysis of the singularities of area-minimizing hypersurfaces modulo $p$ that has been completed in the series of works of De Lellis-Hirsch-Marchese-Stuvard and De Lellis-Hirsch-Marchese-Stuvard-Spolaor, and the work of Minter-Wickramasekera.