M-theory moduli spaces and torsion-free structures

Motivated by the description of $\mathcal{N}=1$ M-theory compactifications to four-dimensions given by Exceptional Generalized Geometry, we propose a way to geometrize the M-theory fluxes by appropriately relating the compactification space to a higher-dimensional manifold equipped with a torsion-free structure. As a non-trivial example of this proposal, we construct a bijection from the set of $Spin(7)$-structures on an eight-dimensional $S^{1}$-bundle to the set of $G_{2}$-structures on the base space, fully characterizing the $G_{2}$-torsion clases when the total space is equipped with a torsion-free $Spin(7)$-structure. Finally, we elaborate on how the higher-dimensional manifold and its moduli space of torsion-free structures can be used to obtain information about the moduli space of M-theory compactifications.Comment: 24 pages. Typos fixed. Minor clarifications adde

NS-NS fluxes in Hitchin's generalized geometry

The standard notion of NS-NS 3-form flux is lifted to Hitchin's generalized geometry. This generalized flux is given in terms of an integral of a modified Nijenhuis operator over a generalized 3-cycle. Explicitly evaluating the generalized flux in a number of familiar examples, we show that it can compute three-form flux, geometric flux and non-geometric Q-flux. Finally, a generalized connection that acts on generalized vectors is described and we show how the flux arises from it.Comment: 21 pages, 1 figure; v3: minor change

Decomposition of some pointed Hopf algebras given by the canonical Nakayama automorphism

Every finite dimensional Hopf algebra is a Frobenius algebra, with Frobenius homomorphism given by an integral. The Nakayama automorphism determined by it yields a decomposition with degrees in a cyclic group. For a family of pointed Hopf algebras, we determine necessary and sufficient conditions for this decomposition to be strongly graded.Comment: 8 page

AdS Vacua, Attractor Mechanism and Generalized Geometries

We consider flux vacua attractor equations in type IIA string theory compactified on generalized geometries with orientifold projections. The four-dimensional N=1 superpotential in this compactification can be written as the sum of the Ramond-Ramond superpotential and a term described by (non)geometric flux charges. We exhibit a simple model in which supersymmetric AdS and Minkowski solutions are classified by means of discriminants of the two superpotentials. We further study various configurations without Ramond-Ramond flux charges. In this case we find supersymmetric AdS vacua both in the case of compactifications on generalized geometries with SU(3) x SU(3) structures and on manifolds with an SU(3)-structure without nongeometric flux charges. In the latter case, we have to introduce correction terms into the prepotential in order to realize consistent vacua.Comment: 35 pages, accepted version in JHE

New families of interpolating type IIB backgrounds

We construct new families of interpolating two-parameter solutions of type IIB supergravity. These correspond to D3-D5 systems on non-compact six-dimensional manifolds which are T^2 fibrations over Eguchi-Hanson and multi-center Taub-NUT spaces, respectively. One end of the interpolation corresponds to a solution with only D5 branes and vanishing NS three-form flux. A topology changing transition occurs at the other end, where the internal space becomes a direct product of the four-dimensional surface and the two-torus and the complexified NS-RR three-form flux becomes imaginary self-dual. Depending on the choice of the connections on the torus fibre, the interpolating family has either N=2 or N=1 supersymmetry. In the N=2 case it can be shown that the solutions are regular.Comment: 20 page

SHARE OF LABOUR COMPENSATION AND AGGREGATE DEMAND – DISCUSSIONS TOWARDS A GROWTH STRATEGY

Economic growth strategies of developing countries have focused in the last decades on expanding their exports. In that scheme, wage compression seems necessary in order to compensate the observed slow productivity pace achieving, therefore, “competitiveness”. The core of this discussion is, undoubtedly, how the national product is appropriated through wages and surplus, i.e. the factorial income distribution. From that viewpoint, this paper discusses the long-term impoverishment of Argentinean workers through two key aspects of the economic process: on one hand, the way in which labour force is allocated, by analysing the relationship between real wage and productivity. On the other, how income is used in the acquisition of consumer goods and capital formation. In order to fully comprehend those trends, this paper recourses to an international comparison with two types of countries: the developed ones (United States of America, France and Japan) and the largest Latin American economies (Brazil and Mexico). As these processes take place in the long run, this paper’s analysis period will start from the 1950s.

Extended geometry and gauged maximal supergravity

We consider generalized diffeomorphisms on an extended mega-space associated to the U-duality group of gauged maximal supergravity in four dimensions, E_7. Through the bein for the extended metric we derive dynamical (field-dependent) fluxes taking values in the representations allowed by supersymmetry, and obtain their quadratic constraints from gauge consistency conditions. A covariant generalized Ricci tensor is introduced, defined in terms of a connection for the generalized diffeomorphisms. We show that for any torsionless and metric-compatible generalized connection, the Ricci scalar reproduces the scalar potential of gauged maximal supergravity. We comment on how these results extend to other groups and dimensions.Comment: 41 pages. v2,v3: minor changes and references adde

Heterotic type IIA duality with fluxes - towards the complete story

In this paper we study the heterotic type IIA duality when fluxes are turned on. We show that many of the known fluxes are dual to each other and claim that certain fluxes on the heterotic side require that the type IIA picture is lifted to M or even F-theory compactifications with geometric fluxes.Comment: 31 pages, references adde