Comments on classical AdS flux vacua with scale separation

Abstract

AdS flux vacua with a parametric separation between the AdS and KK scales have been conjectured to be in the Swampland. We study flux compactifications of massive IIA supergravity with O6 planes which are claimed to allow moduli-stabilised and scale separated AdS3 and AdS4 vacua at arbitrary weak coupling and large volume. A recent refinement of the AdS Distance Conjecture is shown to be inconsistent with this class of AdS3 vacua because the requisite discrete higher form symmetries are absent. We further perform a tree-level study of non-perturbative decays for the nonsupersymmetric versions of the AdS3 solutions, and find that the vacua are stable within this approximation. Finally, we provide an initial investigation of the would-be dual CFT2s and CFT3s. We study roughly a dozen different models and find for all AdS4 DGKT-type vacua that the dual operators to the lightest scalars have integer dimensions. For the putative CFT2 dual theories of the AdS3 vacua we find no integer dimensions for the operators.