Holographic Lorentz and Carroll frames

A bstract Relaxing the Bondi gauge, solution space of three-dimensional gravity in metric formulation has been shown to contain an additional free function that promotes boundary a Lorentz or Carroll frame, asymptotically AdS flat spacetimes. We pursue this analysis and show also admits finite symplectic structure, obtained taking advantage built-in ambiguities. The smoothness limit structure selects prescription which holographic anomaly appears symmetry, rotates frame. This turns out be cohomologically equivalent standard Weyl survives limit, thus predicting existence quantum anomalies conformal Carrollian field theories. revisit these results Chern-Simons formulation, where for admitting smooth follows from variational principle, we compute charge algebra gauge.