Well-clipped cones behave themselves under all finite quotients, the cone conjecture under most

Abstract: We introduce a property of convex cones, being "well-clipped", that is inspired by the work of several complex algebraic geometers on the Morrison-Kawamata cone conjecture. That property is satisfied by movable cones of divisors on various complex projective varieties of Calabi-Yau type, such as abelian varieties and projective hyperk\"ahler manifolds. The property of being well-clipped has the advantage to descend under taking invariants by a finite group action, and to be stable by direct sums. In the class of well-clipped cones, we also provide a simple characterization of those cones that admit a rational polyhedral fundamental domain under some natural group action. We use this framework to prove the movable cone conjecture for finite quotients of various projective varieties of Calabi-Yau type, notably products of projective primitive symplectic varieties, abelian varieties, and smooth rational surfaces underlying klt Calabi-Yau pairs. This entails Enriques manifolds. We deduce that such finite quotients admit finitely many unmarked small $\mathbb{Q}$-factorial modifications, and that the nef cone conjecture holds for them.