Perturbing gauge/gravity duals by a Romans mass

We show how to produce algorithmically gravity solutions in massive IIA (as infinitesimal first order perturbations in the Romans mass parameter) dual to assigned conformal field theories. We illustrate the procedure on a family of Chern--Simons--matter conformal field theories that we recently obtained from the N=6 theory by waiving the condition that the levels sum up to zero.Comment: 30 page

Generalized Kaehler Potentials from Supergravity

We consider supersymmetric N=2 solutions with non-vanishing NS three-form. Building on worldsheet results, we reduce the problem to a single generalized Monge-Ampere equation on the generalized Kaehler potential K recently interpreted geometrically by Lindstrom, Rocek, Von Unge and Zabzine. One input in the procedure is a holomorphic function w that can be thought of as the effective superpotential for a D3 brane probe. The procedure is hence likely to be useful for finding gravity duals to field theories with non-vanishing abelian superpotential, such as Leigh-Strassler theories. We indeed show that a purely NS precursor of the Lunin-Maldacena dual to the beta-deformed N=4 super-Yang-Mills falls in our class.Comment: "38 pages. v3: improved exposition and minor mistakes corrected in sec. 4

The general (2,2) gauged sigma model with three--form flux

We find the conditions under which a Riemannian manifold equipped with a closed three-form and a vector field define an on--shell N=(2,2) supersymmetric gauged sigma model. The conditions are that the manifold admits a twisted generalized Kaehler structure, that the vector field preserves this structure, and that a so--called generalized moment map exists for it. By a theorem in generalized complex geometry, these conditions imply that the quotient is again a twisted generalized Kaehler manifold; this is in perfect agreement with expectations from the renormalization group flow. This method can produce new N=(2,2) models with NS flux, extending the usual Kaehler quotient construction based on Kaehler gauged sigma models.Comment: 24 pages. v2: typos fixed, other minor correction

Localized O6-plane solutions with Romans mass

Orientifold solutions have an unphysical region around their source; for the O6, the singularity is resolved in M-theory by the Atiyah-Hitchin metric. Massive IIA, however, does not admit an eleven-dimensional lift, and one wonders what happens to the O6 there. In this paper, we find evidence for the existence of localized (unsmeared) O6 solutions in presence of Romans mass, in the context of four-dimensional compactifications. As a first step, we show that for generic supersymmetric compactifications, the Bianchi identity for the F_4 RR field follows from constancy of F_0. Using this, we find a procedure to deform any O6-D6 Minkowski compactification at first order in F_0. For a single O6, some of the symmetries of the massless solution are broken, but what is left is still enough to obtain a system of ODEs with as many variables as equations. Numerical analysis indicates that Romans mass makes the unphysical region disappear.Comment: 38 pages, 1 figur

The gauge dual of Romans mass

We deform the recently proposed holographic duality between the ABJM N=6 Chern-Simons-matter theory and type IIA string theory in AdS4xCP3. We add a non-zero Romans mass F_0, whose dual we identify as the sum of the Chern-Simons levels for the two gauge groups. One can naturally identify four different theories, with different amounts of supersymmetry and of flavor symmetry.Comment: 26 pages. v4: Corrected the sign for the probe brane potentia

A Note on Supersymmetric Type II Solutions of Lifshitz Type

We discuss a class of supersymmetric type II non-relativistic solutions with exact or asymptotic scale invariance. As already emerged from previous investigations, we find a clear correspondence between anisotropic d-dimensional vacua and relativistic solutions in (d + 1)-dimensions. We will show that supersymmetric four-dimensional Poincare' invariant backgrounds in type IIB can descend to analogous solutions with anisotropic scaling in t and (x, y). This result can be applied to scale invariant theories, domain walls interpolating between four-dimensional Lifshitz vacua and more general solutions with only asymptotic or approximate scaling behaviour.Comment: Added subsection on hyperscaling violation example