Problems / geometry-topology
geometry-topology / Complex and algebraic geometry; hyperkahler manifolds, Lagrangian fibrations
The strong hyperkahler SYZ conjecture
Theorem 1.1: if c1(L)=0, c1(L) is in the closure of the Kahler cone and qX(c1(L))=0, then L is semiample: some Lm≃f∗A for a surjective connected-fibre map f:X→B onto a normal projective n-dimensional B with A ample, every fibre component Lagrangian of dimension n. Corollary 1.2: in each dimension there are finitely many deformation types with b2≥5. Corollary 1.3 (projective X, via the companion): B≃Pn. Not shown: existence of a nef isotropic class on a given X, or anything for b2≤4 in the finiteness corollary.