Autoequivalences of derived categories via geometric invariant theory

Motivated by a prediction from mirror symmetry, we refine the recent notion of “grade restriction rules” in equivariant derived categories. We produce additional derived autoequivalences of a GIT quotient and propose an interpretation in terms of monodromy of the quantum connection. We generalize this observation by proving a criterion under which a spherical twist autoequivalence factors into a composition of other spherical twists.