In this paper, we show the compatibility of the so-called “dressing field method,” which allows a systematic reduction of gauge symmetries, with the inclusion of diffeomorphisms in the Becchi-Rouet-Stora-Tyutin (BRST) algebra of a gauge theory. The robustness of the scheme is illustrated on two examples where Cartan connections play a significant role. The former is General Relativity, while the latter concerns the second-order conformal structure where one ends up with a BRST algebra handling both the Weyl residual symmetry and diffeomorphisms of spacetime. We thereby provide a geometric counterpart to the BRST cohomological treatment used in Boulanger [J. Math. Phys. 46, 053508 (2005)] in the construction of a Weyl covariant tensor calculus.
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We use the denomination introduced in Ref. 17.
Global aspects require careful consideration which might lead one to look for a better adapted geometrical framework.
This means that G′ is to be suitable for this definition, in particular, it shares the same representations as H (at least the adjoint representation and ρ).
To some extent, H′ is identified to be a subgroup of H along which the gauge invariance can be restored. One may also check that the complement is stable under H.
The reader is referred to Ref. 17, (Chap.12).
Indeed this does not depend on the expression of the shifted ghost.
Due to the successive dressings, the “hat” symbol is dropped out to the benefit of a lower index.