Flat deformations of type IIB S-folds
Adolfo Guarino (Departamento de Física, Universidad de Oviedo, Avda. Federico García Lorca 18, Oviedo, 33007, Spain, Instituto Universitario de Ciencias y Tecnologías Espaciales de Asturias (ICTEA), Calle de la Independencia 13, Oviedo, 33004, Spain); Colin Sterckx (Departamento de Física, Universidad de Oviedo, Avda. Federico García Lorca 18, Oviedo, 33007, Spain, Université Libre de Bruxelles (ULB) and International Solvay Institutes, Service de Physique Théorique et Mathématique, Campus de la Plaine, CP 231, Brussels, B-1050, Belgium)
Type IIB S-folds of the form AdS4 × S1 × S5 have been shown to contain axion-like deformations parameterising flat directions in the 4D scalar potential and corresponding to marginal deformations of the dual S-fold CFT’s. In this note we present a group-theoretical characterisation of such flat deformations and provide a 5D interpretation thereof in terms of $$ \mathfrak{s}(6) $$ -valued duality twists inducing a class of Cremmer-Scherk-Schwarz flat gaugings in a reduction from 5D to 4D. In this manner we establish the existence of two flat deformations for the $$ \mathcal{N} $$ = 4 and SO(4) symmetric S-fold causing a symmetry breaking down to its U(1)2 Cartan subgroup. The result is a new two-parameter family of non-supersymmetric S-folds which are perturbatively stable at the lower-dimensional supergravity level, thus providing the first examples of such type IIB backgrounds.