IIA Solutions Research Articles

An anisotropic extension of Heintzmann IIa solution with vanishing complexity factor

This work is devoted to the construction of a new static and spherical solution for an anisotropic fluid distribution. The construction is based in the framework of gravitational decoupling through a particular case of the extended minimal geometric deformation called 2-steps GD. In this sense, the differential equations arising from gravitational decoupling are closed using the vanishing complexity factor. The Heintzmann IIa solution is used as seed solution. The solution fulfills the fundamental physical acceptability conditions for a restricted set of compactness parameters.

New AdS2 supergravity duals of 4d SCFTs with defects

We construct new families of AdS2× S2× S2 solutions with 4 supercharges in Type II supergravities. We show that subclasses of these solutions can be interpreted in terms of defect branes embedded in 4d mathcal{N} = 4 SYM, or orbifolds thereof. This is explicitly realised by showing that the solutions asymptote locally to AdS5× S5/ℤn, in Type IIB, or its T-dual background, in Type IIA. The latter is a Gaiotto-Maldacena geometry realised on an intersection of D4 and NS5 branes. We extend the Type IIA solutions to include D6 branes, and interpret them as describing backreacted baryon vertices within 4d mathcal{N} = 2 CFTs living in D4-NS5-D6 intersections. We propose explicit quiver quantum mechanics in which the defect branes play the role of colour branes, with the D4 branes of the D4-NS5-D6 intersection becoming flavour branes. These quivers are used to compute the degeneracies of the ground states of the dual super conformal quantum mechanics, that are shown to agree with the holographic expressions.

Spectrum universality properties of holographic Chern-Simons theories

We give a master formula for the spin-2 spectrum of a class of three-dimensional Chern-Simons theories at large N , with flavour group containing SU(3), that arise as infrared fixed points of the D2-brane worldvolume field theory and have AdS4 duals in massive type IIA supergravity. We use this formula to compute the spin-2 spectrum of the individual theories, discuss its supermultiplet structure and, for an mathcal{N} = 2 theory in this class, the spectrum of protected operators with spin 2. We also show that the trace of the Kaluza-Klein graviton mass matrix on the dual AdS4 solutions enjoys certain universality properties. These are shown to relate the class of AdS4 massive IIA solutions under consideration to a similar class of AdS4 solutions of D = 11 supergravity with the same symmetries. Finally, for the mathcal{N} = 2 AdS4 solution in this class, we study the entire spectrum at lowest Kaluza-Klein level and relate it to an analogue solution in D = 11 supergravity.

AdS5 compactifications with punctures in massive IIA supergravity

We find AdS5 solutions holographically dual to compactifications of six- dimensional mathcal{N} = (1, 0) supersymmetric field theories on Riemann surfaces with punctures. We simplify a previous analysis of supersymmetric AdS5 IIA solutions, and with a suitable Ansatz we find explicit solutions organized in three classes, where an O8-D8 stack, D6-and D4-branes are simultaneously present, localized and partially localized. The D4-branes are smeared over the Riemann surface and this is interpreted as the presence of a uniform distribution of punctures. For the first class we identify the corresponding six-dimensional theory as an E-string theory coupled to a quiver gauge theory. The second class of solutions lacks D6-branes and its central charge scales as n5/2, suggesting a five-dimensional origin for the dual field theory. The last class has elements of the previous two.

Preparation of tanshinone ⅡA loaded nanostructured lipid carrier and its in vitro transdermal permeation characteristics

To prepare tanshinone ⅡA loaded nanostructured lipid carrier (Tan ⅡA-NLC), and study its in vitro transdermal permeation characteristics. The Tan ⅡA-NLC was prepared by high pressure homogenization technology and optimized by Box-Behnken design-response surface method, and it was characterized in terms of morphology, particle size, zeta potention, et al. The transdermal permeation of Tan ⅡA-NLC was evaluated by using Franz diffusion cells. The results showed that, the optimal formulation was as follows: drug/lipid materials ratio 88, GMS/MCT ratio 2, emulsifier concentration 1%, average particle size (182±14) nm, polydispersity index PDI (0.190 6±0.024 5), zeta potential (－27.8± 5.4) mV, encapsulation efficiency EE (86.44%±9.26%) and drug loading DL (0.98%±0.18%), respectively. The in vitro transdermal permeation results showed that as compared with Tan ⅡA solution, Tan ⅡA-NLC had lower transdermal permeation amount after applying drug for 24 h, but its retention in the epidermis was 3.18 times that of solution. These results indicated that the prepared Tan ⅡA-NLC could effectively increase the regention of Tan ⅡA in the epidermis, and had a broad application prospect.

AdS4 solutions of massive IIA from dyonic ISO(7) supergravity

Explicit formulae are given for the consistent truncation of massive type IIA supergravity on the six-sphere to the SU(3)--invariant sector of $D=4$ ${\cal N}=8$ supergravity with dyonic ISO(7) gauging. These formulae are then used to construct AdS$_4$ solutions of massive type IIA via uplift on $S^6$ of the critical points of the $D=4$ supergravity with at least SU(3) symmetry. We find a new ${\cal N}=1$ solution with SU(3) symmetry, a new non-supersymmetric solution with SO(6) symmetry, and recover previously known solutions. We quantise the fluxes, calculate the gravitational free energies of the solutions and discuss the stability of the non-supersymmetric ones. Among these, a (previously known) G$_2$--invariant solution is found to be stable.

Non-abelian T-dualizing the resolved conifold with regular and fractional D3-branes

In this paper we obtain new solutions of Type IIA and massive Type IIA supergravity. These solutions are the result of implementing a non-abelian T-duality along the internal $SU(2)$ isometries of several D3-brane configurations on the resolved conifold, studied by Pando Zayas and Tseytlin. We first study the pure NS resolved conifold solution, then we add fluxes by placing a stack of D3-branes at the tip of the resolved conifold and finally we consider the system of regular and fractional D3-branes at the tip. We present the non-abelian T-duals associated with these backgrounds and study their geometries and fluxes. We briefly comment on some field theory features by studying couplings and the central charge of the dual field theory. We also analyze the supersymmetry of the dual solutions and show that for the system of only D3 branes the duality defines a map between backgrounds with $SU(3)$ and orthogonal $SU(2)$ structures.

Braneworld localisation in hyperbolic spacetime

We present a construction employing a type IIA supergravity and 3-form flux background together with an NS5-brane that localises massless gravity near the 5-brane worldvolume. The nonsingular underlying type IIA solution is a lift to 10D of the vacuum solution of the 6D Salam-Sezgin model and has a hyperbolic ${\cal H}^{(2,2)}\times S^1$ structure in the lifting dimensions. A fully back-reacted solution including the NS5-brane is constructed by recognising the 10D Salam-Sezgin vacuum solution as a "brane resolved through transgression." The background hyperbolic structure plays a key r\^ole in generating a mass gap in the spectrum of the transverse-space wave operator, which gives rise to the localisation of gravity on the 6D NS5-brane worldvolume, or, equally, in a further compactification to 4D. Also key to the successful localisation of gravity is the specific form of the corresponding transverse wavefunction Schr\"odinger problem, which asymptotically involves a $V=-1/(4\rho^2)$ potential, where $\rho$ is the transverse-space radius, and for which the NS5-brane source gives rise to a specific choice of self-adjoint extension for the transverse wave operator. The corresponding boundary condition as $\rho\to0$ ensures the masslessness of gravity in the effective braneworld theory. Above the mass gap, there is a continuum of massive states which give rise to small corrections to Newton's law.

AdS6 solutions of type II supergravity

Abstract Very few AdS6 × M4 supersymmetric solutions are known: one in massive IIA, and two IIB solutions dual to it. The IIA solution is known to be unique; in this paper, we use the pure spinor approach to give a classification for IIB supergravity. We reduce the problem to two PDEs on a two-dimensional space Σ. M4 is then a fibration of S2 over Σ; the metric and fluxes are completely determined in terms of the solution to the PDEs. The results seem likely to accommodate near-horizon limits of (p, q)-fivebrane webs studied in the literature as a source of CFT5’s. We also show that there are no AdS6 solutions in eleven-dimensional supergravity.

$ \mathcal{N} $ =1 SUSY AdS4 vacua in IIB SUGRA on group manifolds

We study N=1 compactification of IIB supergravity to AdS4. The internal manifold must have SU(2)-structure. By putting some restrictions on the SU(2) torsion classes, we can perform an exhaustive scan of all possible solutions on group manifolds. We show that sourceless solutions don't exist and that the presence of O5 and O7 orientifolds is mandatory. We also find a new solution and relate it by T-duality to a known type IIA solution with O6 planes.

New examples of flux vacua

Type IIB toroidal orientifolds are among the earliest examples of flux vacua. By applying T-duality, we construct the first examples of massive IIA flux vacua with Minkowski space-times, along with new examples of type IIA flux vacua. The backgrounds are surprisingly simple with no four-form flux at all. They serve as illustrations of the ingredients needed to build type IIA and massive IIA solutions with scale separation. To check that these backgrounds are actually solutions, we formulate the complete set of type II supergravity equations of motion in a very useful form that treats the R-R fields democratically.

Proapoptotic and TRAIL-sensitizing constituents isolated from Salvia militiorrhiza (Danshen)

Natural compounds isolated from medicinal plants are invaluable resources for drug discovery. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising anticancer agent unique by its cancer cell-specific proapoptotic action, but its potential is heavily curbed by acquired resistance. We herein reported for the first time the identification of cytotoxic and TRAIL-sensitizing components of Salvia miltiorrhiza (Danshen), a traditional medicinal plant effective for treating cardiovascular disorders. Specifically, we found that the ethanol extract and its group 5 fraction of S. miltiorrhiza showed evident cytotoxicity against the human lung adenocarcinoma cell line A549 and ovarian adenocarcinoma cell line TOV-21G in a concentration-dependent manner. Likewise, a dose-dependent cytotoxicity was exerted by the standard solutions of cryptotanshinone, tanshinone I and tanshinone IIA, the major components of the group 5 fraction, where tanshinone IIA were most potent and displayed an IC₅₀ of 2.00 ± 0.36 μM and 2.75 ± 0.23 μM for A549 and TOV-21G, respectively. Induction of apoptosis represents an essential mechanism underlying tanshinone IIA-mediated cytotoxic action, as evidenced by the proteolytic processing of PARP upon tanshinone IIA stimulation and, importantly, a marked rescue of the viability of tanshinone IIA-treated cells when co-treatment with the pan-caspase inhibitor z-VAD-fmk. Noteworthy, stimulation with cryptotanshinone, tanshinone I or tanshinone IIA all effectively potentiated TRAIL to reduce viability and inhibit the colony formation capacity of TRAIL-resistant TOV-21G and SKOV3. Collectively, we revealed the proapoptotic and TRAIL-sensitizing components of S. miltiorrhiza and further implicated the potential of developing these active compounds as monotherapeutic agent or TRAIL-based therapy for cancer chemoprevention or chemotherapy.

Assessing a candidate IIA dual to metastable supersymmetry-breaking

Abstract We analyze the space of linearized non-supersymmetric deformations around a IIA solution found by Cvetič, Gibbons, Lü and Pope (CGLP) in hep-th/0101096. We impose boundary conditions aimed at singling out among those perturbations the ones describing the backreaction of anti-D2 branes on the CGLP background. The corresponding supergravity solution is a would-be dual to a metastable supersymmetry-breaking state. However, it turns out that this candidate bulk solution is inevitably riddled with IR divergences of its flux densities and action, whose physical meaning and implications for models of string cosmology call for further investigation.

GALILEAN TYPE IIA BACKGROUNDS AND A MAP

We study nonrelativistic AdS4×CP3 solutions with dynamical exponent 3 in type IIA string theory, both with and without Romans mass. The compactifications to four dimensions are found to describe Proca fields in anti-de Sitter spacetime. This leads us to conclude that the massive and massless IIA theories should be identified in four dimensions and the Romans' mass should be identified with the "flux" along CP3. From supergravity point of view, it suggests a four-dimensional symmetry that rotates Romans mass into the flux along CP3. We also identify M-theory Galilean (ABJM) background which gives rise to the nonrelativistic type IIA solution.

Parameter spaces of massive IIA solutions

We find a new class of N=2 massive IIA solutions whose internal spaces are S^2 fibrations over S^2 x S^2. These solutions appear naturally as massive deformations of the type IIA reduction of Sasaki-Einstein manifolds in M-theory, including Q^{1,1,1} and Y^{p,k}, and play a role in the AdS4/CFT3 correspondence. We use this example to initiate a systematic study of the parameter space of massive solutions with fluxes. We define and study the natural parameter space of the solutions, which is a certain dense subset of R^3, whose boundaries correspond to orbifold or conifold singularities. On a codimension-one subset of the parameter space, where the Romans mass vanishes, it is possible to perform a lift to M-theory; extending earlier work, we produce a family A^{p,q,r} of Sasaki-Einstein manifolds with cohomogeneity one and SU(2) x SU(2) x U(1) isometry. We also propose a Chern-Simons theory describing the duals of the massless and massive solutions.

New supersymmetric AdS4 type II vacua

AbstractWe review the supersymmetric AdS4 ×wℳ︁6 backgrounds of type IIA/IIB supergravity constructed in [1]. In type IIA the supersymmetry is 𝒩 = 2, and the six‐dimensional internal space is locally an S2 bundle over a four‐dimensional Kähler‐Einstein base; in IIB the internal space is the direct product of a circle and a five‐dimensional squashed Sasaki‐Einstein manifold. These backgrounds do not contain any sources, all fluxes (including the Romans mass in IIA) are generally non‐zero, and the dilaton and warp factor are non‐constant. The IIA solutions include the massive deformations of the IIA reduction of the eleven‐dimensional AdS4 × Yp,q solutions, and had been predicted to exist on the basis of the AdS4/CFT3 correspondence.

Classes of AdS4type IIA/IIB compactifications with SU(3) × SU(3) structure

We introduce an ansatz which allows us to solve the supersymmetry equations for warped = 1 AdS4 type II supergravity compactifications of general SU(3) × SU(3) structure. As a byproduct we obtain a set of necessary conditions which every supersymmetric AdS4 vacuum should obey. The case of AdS4 compactifications of IIB on manifolds of static SU(2) structure is examined in detail. Several examples of solutions are presented. In the limit of four-dimensional Minkowski space, we present examples of supersymmetric IIB warped compactifications with partially localized NS5- and D5-branes. We also present `massive' non-supersymmetric AdS4 × 6 solutions of IIA, where 6 can be any six-dimensional Einstein-Kahler manifold.

No-scale supersymmetry breaking vacua and soft terms with torsion

We analyze the conditions to have no-scale supersymmetry breaking solutions of type IIA and IIB supergravity compactified on manifolds of SU(3)-structure. The supersymmetry is spontaneously broken by the intrinsic torsion of the internal space. For type IIB orientifolds with O9 and O5-planes the mass of the gravitino is governed by the torsion class 1, and the breaking is mediated through F-terms associated to descendants of the original = 2 hypermultiplets. For type IIA orientifolds with O6-planes we find two families of solutions, depending on whether the breaking is mediated exclusively by hypermultiplets or by a mixture of hypermultiplets and vector multiplets, the latter case corresponding to a class of Scherk-Schwarz compactifications not dual to any geometric IIB setup. We compute the geometrically induced μ-terms for D5, D6 and D9-branes on twisted tori, and discuss the patterns of soft-terms which arise for pure moduli mediation in each type of breaking. As for D3 and D7-branes in presence of 3-form fluxes, the effective scalar potential turns out to possess interesting phenomenological properties.

Generalised geometry for M-theory

Generalised geometry studies structures on a d-dimensional manifold with a metric and 2-form gauge field on which there is a natural action of the group SO(d,d). This is generalised to d-dimensional manifolds with a metric and 3-form gauge field on which there is a natural action of the group $E_{d}$. This provides a framework for the discussion of M-theory solutions with flux. A different generalisation is to d-dimensional manifolds with a metric, 2-form gauge field and a set of p-forms for $p$ either odd or even on which there is a natural action of the group $E_{d+1}$. This is useful for type IIA or IIB string solutions with flux. Further generalisations give extended tangent bundles and extended spin bundles relevant for non-geometric backgrounds. Special structures that arise for supersymmetric backgrounds are discussed.

Supergravitypp-wave solutions with 28 and 24 supercharges

We conduct an exhaustive search for solutions of IIA and IIB supergravity with augmented supersymmetry. We find a two-parameter family of IIB solutions preserving 28 supercharges, as well as several other IIA and IIB families of solutions with 24 supercharges. Given the simplicity of the pp-wave solution, the algorithm described here represents a systematic way of classifying all such solutions with augmented supersymmetry. By T-dualizing some of these solutions we obtain exact non-pp wave supergravity solutions (with 8 or 16 supercharges), which can be interpreted as perturbations of the AdS-CFT correspondence with irrelevant operators.