Quantizing a Non-locally Massive 2-form Model

A non-local yet gauge-invariantly massive 2-form model is considered that leads to local and unitary dynamics upon proper gauge-fixing. Since canonical momenta cannot be defined owing to the non-locality, consistent quantization of this system warrants particular care. We construct the Dirac brackets and covariant commutators for this model, followed by its path integral quantization, leading to consistent results. These treatments underline the most efficient way to extract the physical modes and the subsequent spectrum free from infrared ambiguity. Physically the massive 2-form represents a spin-1 excitation, with potential application to string theory and cosmology, that can mediate a screened interaction when topologically coupled to fermions.