Speaker
Description
We study Hamiltonian form of unfree gauge symmetry where the gauge parameters have to obey differential equations. The phenomenon of the unfree gauge symmetry is clarified from viewpoint of involution relations between Hamiltonian and constraints. Given the involution relations for the first-class constraints of all generations, we provide explicit formulas for unfree gauge transformations in the Hamiltonian form, including the differential equations constraining gauge parameters. We adjust the BFV-BRST Hamiltonian quantization method for the case of unfree gauge symmetry. The main distinction is in the content of the non-minimal sector and gauge fixing procedure. For the case when there are no higher-order ghost vertices, we deduce from the phase-space path integral the modified FP quantization rules such that account for the unfree gauge symmetry by imposing corresponding constraints on the ghosts. These ghost constraints mirror the equations imposed on gauge parameters in Hamiltonian formalism. The general formalism is exemplified by specific models, including linearized unimodular gravity.
