The Cautis-Logvinenko conjecture

Abstract

For a finite subgroup $G\subset \mathrm{SL}(3,\mathbb{C})$, the Cautis--Logvinenko conjecture states that for each nontrivial irreducible representation $\rho$ of $G$, the image of the sheaf ${\mathcal{O}}_0\otimes \rho$ under the derived equivalence of Bridgeland--King--Reid is a pure sheaf on the $G$-Hilbert scheme. We prove a strong form of this conjecture in complete generality, and in doing so, we compute the relevant sheaf explicitly whenever its support is of dimension one. Our main result implies that a matrix defining the Gale dual of the linearisation map is sign-coherent, thereby allowing us to read off the support and cohomological degree of the pure sheaves directly from the matrix.

v2: 22 pages, we prove the conjecture in complete generality, without having to assume that there are no loops at certain vertices in the McKay quiver. Coauthor added