We study the thermodynamics of $AdS_4$ black hole solutions of Einstein-Maxwell theory that are accelerating, rotating, and carry electric and magnetic charges. We focus on the class for which the black hole horizon is a spindle and can be uplifted o
n regular Sasaki-Einstein spaces to give solutions of $D=11$ supergravity that are free from conical singularities. We use holography to calculate the Euclidean on-shell action and to define a set of conserved charges which give rise to a first law. We identify a complex locus of supersymmetric and non-extremal solutions, defined through an analytic continuation of the parameters, upon which we obtain a simple expression for the on-shell action. A Legendre transform of this action combined with a reality constraint then leads to the Bekenstein-Hawking entropy for the class of supersymmetric and extremal black holes.
We construct supersymmetric $AdS_5times Sigma$ solutions of $D=7$ gauged supergravity, where $Sigma$ is a two-dimensional orbifold known as a spindle. These uplift on $S^4$ to solutions of $D=11$ supergravity which have orbifold singularites. We argu
e that the solutions are dual to $d=4$, $mathcal{N}=1$ SCFTs that arise from $N$ M5-branes wrapped on a spindle, embedded as a holomorphic curve inside a Calabi-Yau three-fold. In contrast to the usual topological twist solutions, the superconformal R-symmetry mixes with the isometry of the spindle in the IR, and we verify this via a field theory calculation, as well as reproducing the gravity formula for the central charge.
We construct a continuous one parameter family of $AdS_4times S^1times S^5$ S-fold solutions of type IIB string theory which have nontrivial $SL(2,mathbb{Z})$ monodromy in the $S^1$ direction. The solutions span a subset of a conformal manifold that
contains the known $mathcal{N}=4$ S-fold SCFT in $d=3$, and generically preserve $mathcal{N}=2$ supersymmetry. We also construct RG flows across dimensions, from $AdS_5times S^5$, dual to $mathcal{N}=4$, $d=4$ SYM compactified with a twisted spatial circle, to various $AdS_4times S^1times S^5$ S-fold solutions, dual to $d=3$ SCFTs. We construct additional flows between the $AdS_5$ dual of the Leigh-Strassler SCFT and an $mathcal{N}=2$ S-fold as well as RG flows between various S-folds.
We construct infinite new classes of $AdS_4times S^1times S^5$ solutions of type IIB string theory which have non-trivial $SL(2,mathbb{Z})$ monodromy along the $S^1$ direction. The solutions are supersymmetric and holographically dual, generically, t
o $mathcal{N}=1$ SCFTs in $d=3$. The solutions are first constructed as $AdS_4times mathbb{R}$ solutions in $D=5$ $SO(6)$ gauged supergravity and then uplifted to $D=10$. Unlike the known $AdS_4times mathbb{R}$ S-fold solutions, there is no continuous symmetry associated with the $mathbb{R}$ direction. The solutions all arise as limiting cases of Janus solutions of $d=4$, $mathcal{N}=4$ SYM theory which are supported both by a different value of the coupling constant on either side of the interface, as well as by fermion and boson mass deformations. As special cases, the construction recovers three known S-fold constructions, preserving $mathcal{N}=1,2$ and 4 supersymmetry, as well as a recently constructed $mathcal{N}=1$ $AdS_4times S^1times S^5$ solution (not S-folded). We also present some novel one-sided Janus solutions that are non-singular.
We study solutions in the Plebanski--Demianski family which describe an accelerating, rotating and dyonically charged black hole in $AdS_4$. These are solutions of $D=4$ Einstein-Maxwell theory with a negative cosmological constant and hence minimal
$D=4$ gauged supergravity. It is well known that when the acceleration is non-vanishing the $D=4$ black hole metrics have conical singularities. By uplifting the solutions to $D=11$ supergravity using a regular Sasaki-Einstein $7$-manifold, $SE_7$, we show how the free parameters can be chosen to eliminate the conical singularities. Topologically, the $D=11$ solutions incorporate an $SE_7$ fibration over a two-dimensional weighted projective space, $mathbb{WCP}^1_{[n_-,n_+]}$, also known as a spindle, which is labelled by two integers that determine the conical singularities of the $D=4$ metrics. We also discuss the supersymmetric and extremal limit and show that the near horizon limit gives rise to a new family of regular supersymmetric $AdS_2times Y_9$ solutions of $D=11$ supergravity, which generalise a known family by the addition of a rotation parameter. We calculate the entropy of these black holes and argue that it should be possible to derive this from certain ${cal N}=2$, $d=3$ quiver gauge theories compactified on a spinning spindle with appropriate magnetic flux.
We construct supersymmetric $AdS_3times Sigma$ solutions of minimal gauged supergravity in $D=5$, where $Sigma$ is a two-dimensional orbifold known as a spindle. Remarkably, these uplift on $S^5$, or more generally on any regular Sasaki-Einstein mani
fold, to smooth solutions of type IIB supergravity. The solutions are dual to $d=2$, $mathcal{N}=(0,2)$ SCFTs and we show that the central charge for the gravity solution agrees with a field theory calculation associated with D3-branes wrapped on $Sigma$. Unlike for smooth $Sigma$ the superconformal R-symmetry mixes with the $U(1)$ isometry of the spindle.
We study mass deformations of $mathcal{N}=4$, $d=4$ SYM theory that are spatially modulated in one spatial dimension and preserve some residual supersymmetry. We focus on generalisations of $mathcal{N}=1^*$ theories and show that it is also possible,
for suitably chosen supersymmetric masses, to preserve $d=3$ conformal symmetry associated with a co-dimension one interface. Holographic solutions can be constructed using $D=5$ theories of gravity that arise from consistent truncations of $SO(6)$ gauged supergravity and hence type IIB supergravity. For the mass deformations that preserve $d=3$ superconformal symmetry we construct a rich set of Janus solutions of $mathcal{N}=4$ SYM theory which have the same coupling constant on either side of the interface. Limiting classes of these solutions give rise to RG interface solutions with $mathcal{N}=4$ SYM on one side of the interface and the Leigh-Strassler (LS) SCFT on the other, and also to a Janus solution for the LS theory. Another limiting solution is a new supersymmetric $AdS_4times S^1times S^5$ solution of type IIB supergravity.
We construct gravitational solutions that holographically describe two different $d=4$ SCFTs joined together at a co-dimension one, planar RG interface and preserving $d=3$ superconformal symmetry. The RG interface joins $mathcal{N}=4$ SYM theory on
one side with the $mathcal{N}=1$ Leigh-Strassler SCFT on the other. We construct a family of such solutions, which in general are associated with spatially dependent mass deformations on the $mathcal{N}=4$ SYM side, but there is a particular solution for which these deformations vanish. We also construct a Janus solution with the Leigh-Strassler SCFT on either side of the interface. Gravitational solutions associated with superconformal interfaces involving ABJM theory and two $d=3$ $mathcal{N}=1$ SCFTs with $G_2$ symmetry are also discussed and shown to have similar properties, but they also exhibit some new features.
We study black hole solutions of $D=4$ Einstein-Maxwell theory coupled to a charged scalar field that are holographically dual to a $d=3$ conformal field theory with a non-vanishing chemical potential and constant magnetic field. We numerically const
ruct black hole solutions that are dual to a superfluid phase with a periodic lattice of vortices. For the specific model we investigate, we find that the thermodynamically preferred configuration is given by a triangular lattice and moreover the vortices are associated with the lowest Landau level. We also construct black holes describing a lattice of vortices associated with the next to lowest Landau level and while theses are not thermodynamically preferred they exhibit some interesting features that could be realised for other holographic models.
We continue our study of a general class of $mathcal{N}=2$ supersymmetric $AdS_3times Y_7$ and $AdS_2times Y_9$ solutions of type IIB and $D=11$ supergravity, respectively. The geometry of the internal spaces is part of a general family of GK geometr
ies, $Y_{2n+1}$, $nge 3$, and here we study examples in which $Y_{2n+1}$ fibres over a Kahler base manifold $B_{2k}$, with toric fibres. We show that the flux quantization conditions, and an action function that determines the supersymmetric $R$-symmetry Killing vector of a geometry, may all be written in terms of the master volume of the fibre, together with certain global data associated with the Kahler base. In particular, this allows one to compute the central charge and entropy of the holographically dual $(0,2)$ SCFT and dual superconformal quantum mechanics, respectively, without knowing the explicit form of the $Y_7$ or $Y_9$ geometry. We illustrate with a number of examples, finding agreement with explicit supergravity solutions in cases where these are known, and we also obtain new results. In addition we present, en passant, new formulae for calculating the volumes of Sasaki-Einstein manifolds.
