3D Supergravity from wrapped D3-branes

AdS_3 solutions dual to N = (0,2) SCFTs arise when D3-branes wrap Kahler two-cycles in manifolds with SU(4) holonomy. Here we review known AdS_3 solutions and identify the corresponding three-dimensional gauged supergravities, solutions of which uplift to type IIB supergravity. In particular, we discuss gauged supergravities dual to twisted compactifications on Riemann surfaces of both N=4 SYM and N =1 SCFTs with Sasaki-Einstein duals. We check in each case that c-extremization gives the exact central charge and R symmetry. For completeness, we also study AdS_3 solutions from intersecting D3-branes, generalise recent KK reductions of Detournay & Guica and identify the underlying gauged supergravities. Finally, we discuss examples of null-warped AdS_3 solutions to three-dimensional gauged supergravity, all of which embed in string theory.Comment: v1 48 pages; v2 two references added, to appear in JHE

Hints of 5d Fixed Point Theories from Non-Abelian T-duality

In this paper we investigate the properties of the putative 5d fixed point theory that should be dual, through the holographic correspondence, to the new supersymmetric AdS(6) solution constructed in Lozano et al. This solution is the result of a non-Abelian T-duality transformation on the known supersymmetric AdS(6) solution of massive Type IIA. The analysis of the charge quantization conditions seems to put constraints on the global properties of the background, which, combined with the information extracted from considering probe branes, suggests a 2-node quiver candidate for the dual CFT.Comment: v2, typos corrected, comments added, to appear in JHE

Supersymmetric AdS_6 via T-duality

We present a new supersymmetric AdS_6 solution of type IIB supergravity with SU(2) isometry. Through the AdS/CFT correspondence, this has potentially very interesting implications for 5d fixed point theories. This solution is the result of a non-Abelian T-duality on the known supersymmetric AdS_6 solution of massive IIA. The SU(2) R-symmetry is untouched, leading to sixteen supercharges and preserved supersymmetry.Comment: 4 pages, published versio

Inevitable manifestation of wiggles in the expansion of the late Universe

Using the fact that the comoving angular diameter distance to the last scattering surface is strictly constrained almost model independently, we show that, for any model agreeing with the standard $\Lambda$CDM model on its background dynamics at $z\sim0$ and size of the comoving sound horizon at last scattering, the deviations of the Hubble radius from the one of the standard $\Lambda$CDM model must be a member of the set of admissible wavelets. The family of models characterized by this framework also offers nontrivial oscillatory behaviours in various functions that define the kinematics of the Universe, even when the wavelets themselves are very simple. We also discuss the consequences of attributing these kinematics to, first, dark energy, and second, varying gravitational coupling strength. Utilizing some simplest wavelets, we demonstrate the competence of this framework in describing the baryon acoustic oscillation (BAO) data without any modifications to the agreement with cosmic microwave background measurements. This framework also provides a natural explanation for the bumps found in nonparametric observational reconstructions of the Hubble parameter and dark energy density as compensations of the dips suggested by some BAO data, and questions the physical reality of their existence. We note that utilizing this framework on top of the models that agree with both the cosmic microwave background and local $H_0$ measurements but are held back by BAO data, one may resurrect these models through the wiggly nature of wavelets that can naturally accommodate the BAO data. Finally, we also suggest narrowing the plausible set of admissible wavelets to further improve our framework by imposing conditions from expected kinematics of a viable cosmological model or first principle fundamental physics such as energy conditions.Comment: 16 pages, 4 figures; matches the version published in Physical Review

Consistent reductions from D=11 beyond Sasaki-Einstein

The most general class of warped AdS5 x M6 supersymmetric solutions in D=11 supergravity permit a consistent truncation to D=5 N=2 minimal gauged supergravity. Here we extend this truncation, for a particular subclass of M6 manifolds, to D=5 N=4 gauged supergravity coupled to two vector multiplets. We obtain the reduction ansatz by T-duality of a recently discussed type IIB truncation on a generic Sasaki-Einstein five-fold, which becomes non-trivial in D=11 and displays non-standard features due to the G-structure of the internal M6. Using this truncation, we construct two new classes of warped and unwarped non-supersymmetric AdS5 M-theory backgrounds. We also comment on possible extensions of the reduction ansatz to the general class of M6 geometries.Comment: Seven double column pages; v2: Acknowledgement added, version to be published in Phys. Lett.