Unitary truncations and critical gravity: a toy model

摘要

We investigate a higher-derivative scalar field model in a fixed d + 1 dimensional AdS background as a toy model for a gravitational dual to a higher-rank logarithmic CFT. The holographic two-point correlation functions on the boundary agree with higher-rank LCFT correlation functions. For odd rank, the theory allows for a truncation to a nontrivial subspace with non-negative scalar product. We discuss possible implications for higherderivative critical gravity theories.