U2 - 5017
AdS3 scale separation in Type IIB and non-abelian orbifolds
A prominent challenge in string compactifications is to realize a parametric hierarchy between the cosmological constant and the Kaluza-Klein scale, which is called scale separation and which is necessary for obtaining genuine lower-dimensional effective theories. In this talk, I will present new constructions of scale-separated solutions in Type IIB string theory based on orientifold compactifications on nilmanifolds with G2-structure. I will focus in particular on the simplest example: an AdS3 solution obtained from a compactification on a Z_2^3 orbifold of the product of a three-dimensional nilmanifold and a four-torus. In addition to exhibiting parametric scale separation within a controlled regime, this solution features a scalar mass spectrum that gives rise to integer conformal dimensions in the putative dual CFT. Recent work has suggested that theories with such spectra may suffer from pathologies when certain cubic couplings are present. I will show that this issue indeed arises in the present setup and demonstrate how it can be resolved by replacing the abelian orbifold with a suitable non-abelian orbifold construction.