R-symmetry gauged 6D (1,0) supergravities free from all local anomalies, with gauge groups $G\times G_R$ where $G_R$ is the R-symmetry group and $G$ is semisimple with rank greater than one, and which have no hypermultiplet singlets, are extremely rare. There are three such models known in which the gauge symmetry group is $G_1\times G_2 \times U(1)_R$ where the first two factors are $ \left(E_6/{\mathbb{Z}_3}\right) \times E_7$, $ G_2 \times E_7 $ and $F_4 \times Sp(9)$. These are models with single tensor multiplet, and hyperfermions in the $(1,912)$, $(14,56)$ and $(52,18)$ dimensional representations of $G_1\times G_2$, respectively. So far it is not known if these models follow from string theory. We highlight key properties of these theories, and examine constraints which may arise from the consistency of the quantization of anomaly coefficients formulated in their strongest form by Monnier and Moore. Assuming that the gauged models accommodate dyonic string excitations, we find that these constraints are satisfied only by the model with the $F_4 \times Sp(9)\times U(1)_R$ symmetry. We also discuss aspects of dyonic strings and potential caveats they may pose in applying the stated consistency conditions to the $R$-symmetry gauged models.
It is shown that the Scherk-Schwarz reduction of M-theory in the Berman-Perry duality invariant formalism to 6 and 5 dimensions reproduces the known structures of gauged supergravities that are normally associated to non-geometric compactifications. The local symmetries defined by the generalised Lie derivative reduce to gauge transformations that exactly match those given by the embedding tensor of gauged supergravity.
We give a general review of extended supergravities and their gauging using the duality-covariant embedding tensor formalism. Although the focus is on four-dimensional theories, an overview of the gauging procedure and the related tensor hierarchy in the higher-dimensional models is given. The relation of gauged supergravities to flux compactifications is discussed and examples are worked out in detail.
We consider the reduction of the duality invariant approach to M-theory by a U-duality group valued Scherk-Schwarz twist. The result is to produce potentials for gauged supergravities that are normally associated with non-geometric compactifications. The local symmetry reduces to gauge transformations with the gaugings exactly matching those of the embedding tensor approach to gauged supergravity. Importantly, this approach now includes a nontrivial dependence of the fields on the extra coordinates of the extended space.
Supergravities with gauged R-symmetry and Minkowski vacua allow for spontaneous supersymmetry breaking and, as such, provide a framework for building supergravity models of phenomenological relevance. In this letter we initiate the study of double-copy constructions for these supergravities. We argue that, on general grounds, we expect their scattering amplitudes to be described by a double copy of the type: (Higgsed gauge theory) x (gauge theory with broken SUSY). We present a simple realization in which the resulting supergravity has U(1)_R gauge symmetry, spontaneously-broken N=2 supersymme…
Which theories have a higher dimensional origin in String/M-theory is a non trivial question and it is still far from being understood in the constrained scenario of maximal supergravities. After 35 years of progress in this direction we have found supporting evidence in favor of the idea that every electric maximal supergravity in 4 dimensions can be uplifted to M-theory. We will review the current understanding of this problem with special emphasis in the uplifting of non compact supergravities and their relation with Exceptional Generalised Geometry.
We study dimensional reductions of M-theory/type II strings down to 6D in the presence of fluxes and spacetime filling branes and orientifold planes of different types. We classify all inequivalent orientifold projections giving rise to $\mathcal{N}=(1,1)$ supergravities in 6D and work out the embedding tensor/fluxes dictionary for each of those. Finally we analyze the set of vacua for the different classes of reductions and find an abundance of "no-scale" type Minkowski vacua, as well as a few novel examples of (A)dS extrema.
We discuss duality orbits and symplectic deformations of D=4 gauged supergravity theories, with focus on N$\ge$2. We provide a general constructive framework for computing symplectic deformations starting from a reference gauging, and apply it to many interesting examples. We prove that no continuous deformations are allowed for Fayet-Iliopoulos gaugings of the N=2 STU model and in particular that any $ω$ deformation is classically trivial. We further show that although in the N=6 truncation of SO(8) maximal supergravity the $ω$ parameter can be dualized away, in the 'twin' N=2 truncation $ω$ …
We study the general deformations of maximal eight-dimensional supergravity by using the embedding tensor approach. The scalar potential induced by these gaugings is determined. Subsequently, by combining duality covariance arguments and algebraic geometry techniques, we find the complete set of critical points of the scalar potential. Remarkably, up to SO(2) X SO(3) rotations there turns out to be a unique theory admitting extrema. The gauge group of the theory is CSO(2,0,1).
We provide the M-theory uplift of de Sitter vacua of SO(5,3) and SO(4,4) gaugings of maximal supergravity in 4 dimensions. We find new non-compact backgrounds that are squashed hyperboloids with non-trivial flux for the 3-form potential. The uplift requires a new non-linear ansatz for the 11-dimensional metric and for the 3-form potential that reduces to the known one leading to the 7-sphere solution in the case of the SO(8) gauging.
Dipartimento di Fisica e Astronomia “Galileo Galilei”, Università di Padova（帕多瓦大学伽利略·伽利莱物理与天文系）；INFN, Sezione di Padova（意大利国家核物理研究所帕多瓦分部）；Université Libre de Bruxelles (ULB)（布鲁塞尔自由大学）；International Solvay Institutes（国际索尔维研究所）
We perform a systematic search for static solutions in different sectors of 5d $N=8$ supergravities with compact and non-compact gauged R-symmetry groups, finding new and listing already known backgrounds. Due to the variety of possible gauge groups and resulting scalar potentials, the maximally symmetric vacua we encounter in these theories can be Minkowski, de Sitter, or anti-de Sitter. There exist BPS and non-BPS near-horizon geometries and full solutions with all these three types of asymptotics, corresponding to black holes, branes, strings, rings, and other black objects with more exotic…
We establish the precise correspondence between Type-IIA flux compactifications preserving an exact or spontaneously broken N=4 supersymmetry in four dimensions, and gaugings of their effective N=4 supergravities. We exhibit the explicit map between fluxes and Bianchi identities in the higher-dimensional theory and generalized structure constants and Jacobi identities in the reduced theory, also detailing the origin of gauge groups embedded at angles in the duality group. We present AdS4 solutions of the massive Type-IIA theory with spontaneous breaking to N=1, at small string coupling and lar…
We construct an exact time-dependent charged dilaton C-metric in four-dimensional ${\cal N}=4$ gauged supergravity. The scalar field drives the time evolution by transferring energy to the black holes, thereby causing their masses to increase and their acceleration to decrease. The values of the electric/magnetic and scalar charges determine three regions of potential time evolution. This solution holographically describes a strongly-coupled three-dimensional conformal field theory on the background of an evolving black hole. We also find new static charged dilaton C-metrics, which arise in fo…
We study N=2 vacua in spontaneously broken N=4 electrically gauged supergravities in four space-time dimensions. We argue that the classification of all such solutions amounts to solving a system of purely algebraic equations. We then explicitly construct a special class of consistent N=2 solutions and study their properties. In particular we find that the spectrum assembles in N=2 massless or BPS supermultiplets. We show that (modulo U(1) factors) arbitrary unbroken gauge groups can be realized provided that the number of N=4 vector multiplets is large enough. Below the scale of partial super…
This thesis analyses gauged supergravities in various dimensions and their possible origin from compactifications of string theory. In the effective description the fluxes appear in the theory as deformation parameters generating a potential for the scalar fields. Physics after compactification is only sensitive to the orbits of the global symmetry group, in that gaugings lying in the same orbit are related by duality transformations. Given a certain gauged supergravity containing non-geometric fluxes, we discuss in dimension seven and higher whether there exists a duality transformation that …
We investigate reductions of M-theory beyond twisted tori by allowing the presence of KK6 monopoles (KKO6-planes) compatible with N=4 supersymmetry in four dimensions. The presence of KKO6-planes proves crucial to achieve full moduli stabilisation as they generate new universal moduli powers in the scalar potential. The resulting gauged supergravities turn out to be compatible with a weak G2 holonomy at N=1 as well as at some non-supersymmetric AdS4 vacua. The M-theory flux vacua we present here cannot be obtained from ordinary type IIA orientifold reductions including background fluxes, D6-br…
We first derive a class of six-dimensional (1,0) gauged supergravities arising from threefold compactifications of F-theory with background fluxes. The derivation proceeds via the M-theory dual reduction on an SU(3)-structure manifold with four-form G_4-flux. We then show that vacuum solutions of these six-dimensional theories describes four-dimensional flat space times a compact two-dimensional internal space with additional localized sources. This induces a spontaneous compactification to four space-time dimensions and breaks the supersymmetry from N=2 to N=1, which allows the reduced theory…
In an ungauged supergravity theory, the presence of a \emph{scalar potential} is allowed only for the minimal $\N=1$ case. In extended supergravities, a non-trivial scalar potential can be introduced without explicitly breaking supersymmetry only through the so-called \emph{gauging procedure}. The latter consists in promoting a suitable global symmetry group to local symmetry to be gauged by the vector fields of the theory. Gauged supergravities provide a valuable approach to the study of superstring flux-compactifications and the construction of phenomenologically viable, string-inspired mode…
We study supersymmetric $AdS_4$ black holes in matter-coupled $N=3$ and $N=4$ gauged supergravities in four dimensions. In $N=3$ theory, we consider $N=3$ gauged supergravity coupled to three vector multiplets and $SO(3)\times SO(3)$ gauge group. The resulting gauged supergravity admits two $N=3$ supersymmetric $AdS_4$ vacua with $SO(3)\times SO(3)$ and $SO(3)$ symmetries. We find an $AdS_2\times H^2$ solution with $SO(2)\times SO(2)$ symmetry and an analytic solution interpolating between this geometry and the $SO(3)\times SO(3)$ symmetric $AdS_4$ vacuum. For $N=4$ gauged supergravity coupled…
We study $AdS_3$ supersymmetric vacua in N=4 and N=8, three dimensional gauged supergravities, with scalar manifolds $(\frac{SO(4,4)}{SO(4)\times SO(4)})^2$ and $\frac{SO(8,8)}{SO(8)\times SO(8)}$, non-semisimple Chern-Simons gaugings $SO(4)\ltimes {\bf R}^6$ and $(SO(4)\ltimes {\bf R}^6)^2$, respectively. These are in turn equivalent to SO(4) and $SO(4)\times SO(4)$ Yang-Mills theories coupled to supergravity. For the N=4 case, we study renormalization group flows between UV and IR $AdS_3$ vacua with the same amount of supersymmetry: in one case, with (3,1) supersymmetry, we can find an analy…
We construct and analyze BPS black hole solutions in gauged N=2, D=4 supergravity with charged hypermultiplets. A class of solutions can be found through spontaneous symmetry breaking in vacua that preserve maximal supersymmetry. The resulting black holes do not carry any hair for the scalars. We demonstrate this with explicit examples of both asymptotically flat and anti-de Sitter black holes. Next, we analyze the BPS conditions for asymptotically flat black holes with scalar hair and spherical or axial symmetry. We find solutions only in cases when the metric contains ripples and the vector …
This thesis is focused on supersymmetric objects in gauged supergravities and their interpretation in string theory. Three particular theories are considered and analyzed: matter-coupled $d=4, 5$ abelian gauged supergravities with 8 supercharges and minimal $d=7$ gauged supergravity with 16 supercharges. Respectively in the $d=4$ and $d=5$ cases, the BPS first-order flows of static extremal black holes and black strings are studied using the Hamilton-Jacobi formalism. The attractor mechanism is formulated for the case of couplings to hypermultiplets and two exact BPS black hole solutions are d…
In this paper we obtain the complete classification of the inequivalent classes of M2-brane symplectic torus bundles with monodromy in $SL(2,Z)$ and their precise U-duality relations among them. There are eight inequivalent classes of bundles whose monodromy groups, at low energies, are in correspondence with the gauging groups of the eight type II gauged supergravities in nine dimensions. Four of those have been previously found and they correspond to the 'type IIB side'. In this paper we provide the explicit realization of the remaining four classes associated to the 'type IIA side'. The pre…
在最近构造了最大（N=16）规范超引力的基础上，我们导出了D=3，N=8的规范超引力作为相应的标量流形SO（8，n）/（SO（8）× SO（n））的非规范理论的变形.作为特例，我们恢复了N=（4，4）的SO（4）= SO（3）_L x SO（3）_R理论，它再现了D=6，N=（2，0）超引力在AdS_3 x S^3上紧化的对称性和无质量谱.
