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arXiv · hep-th/0612221

Reducible Gauge Algebra of BRST-Invariant Constraints

I. A. Batalin·K. Bering
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Abstract

We show that it is possible to formulate the most general first-class gauge algebra of the operator formalism by only using BRST-invariant constraints. In particular, we extend a previous construction for irreducible gauge algebras to the reducible case. The gauge algebra induces two nilpotent, Grassmann-odd, mutually anticommuting BRST operators that bear structural similarities with BRST/anti-BRST theories but with shifted ghost number assignments. In both cases we show how the extended BRST algebra can be encoded into an operator master equation. A unitarizing Hamiltonian that respects the two BRST symmetries is constructed with the help of a gauge-fixing Boson. Abelian reducible theories are shown explicitly in full detail, while non-Abelian theories are worked out for the lowest reducibility stages and ghost momentum ranks.

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I. A. Batalin, K. Bering. 2007-11-07. Reducible Gauge Algebra of BRST-Invariant Constraints. https://doi.org/10.1016/j.nuclphysb.2007.02.013

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