Symmetries beget symmetries: ghostly higher-form symmetries and the descent equation

Viewed through the lens of the Batalin-Vilkovisky formalism, we demonstrate that higher-form currents with nonzero ghost number also define higher-form symmetries, directly analogous to the standard higher-form symmetries with ghost number zero. These ghostly higher symmetries descend from and into conventional higher-form symmetries via chains of descent equations familiar from the theory of anomalies and topological field theories. We give examples of such chains of ghostly symmetries in Maxwell theory, Abelian and non-Abelian higher gauge theory, Yang-Mills theory, and beyond.