1,721,032 research outputs found
Gauge Charges from Supergravity
No full textSome recent results in the study of four dimensional supergravity flux compactifications are reviewed, discussing in particular the role of torsion on the compactification manifold in generating gauge charges for the effective four dimensional theories.Some recent results in the study of four dimensional supergravity flux compactifications are reviewed, discussing in particular the role of torsion on the compactification manifold in generating gauge charges for the effective four dimensional theories.Some recent results in the study of four dimensional supergravity flux compactifications are reviewed, discussing in particular the role of torsion on the compactification manifold in generating gauge charges for the effective four dimensional theories.Some recent results in the study of four dimensional supergravity flux compactifications are reviewed, discussing in particular the role of torsion on the compactification manifold in generating gauge charges for the effective four dimensional theories
'Nonchiral' primary superfields in the AdS(d+1) / CFT(d) correspondence
No full textWe consider some long multiplets describing bulk massive excitations of M-theory two-branes and IIB string three-branes which correspond to ‘nonchiral' primary operators of the boundary OSp(8/4) and SU(2,2/4) superconformal field theories. Examples of such multiplets are the ‘radial' modes on the branes, including up to spin 4 excitations, which may be then considered as prototypes of states which are not described by the K-K spectrum of the corresponding supergravity theories on Ad S4 × S7 and Ad S5 × S5, respectivel
Issues on Black Holes in Four Dimensional Supergravity
No full textWe discuss some issues related to spherically symmetric, asymptotically flat black hole solutions in four dimensional supergravity. Particular emphasis will be placed on their properties relative to the electric-magnetic duality symmetry of the theory. We first elaborate on the description of these solutions in terms of an autonomous Hamiltonian system. This will provide us with a useful framework where to study the description of specific classes of solutions in terms of a first order “gradient flow” dynamical system of equations defined by a superpotential W, solution to the Hamilton-Jacobi equation. Regular extremal solutions play a special role in this analysis sice the dynamical system exhibits an asymptotically stable equilibrium point for the scalar fields in correspondence to the horizon (attractor mechanism). We also comment on the relation between this formalism and the three-dimensional description of spherically symmetric black holes as geodesics on suitable pseudo-Riemannian manifolds
Extremal Black Holes in Supergravity and the Bekenstein-Hawking Entropy
No full textAbstract: We review some results on the connection among supergravity central charges, BPS states and Bekenstein-Hawking entropy. In particular, N = 2 super-gravity in four dimensions is studied in detail. For higher N supergravities we just give an account of the general theory specializing the discussion to the N = 8 case when one half of supersymmetry is preserved. We stress the fact that for extremal supergravity black holes the entropy formula is topological, that is the entropy turns out to be a moduli independent quantity and can be written in terms of invariants of the duality group of the supergravity theory
N=1 and N=2 pure supergravities on a manifold with boundary
Full text linkWorking in the geometric approach, we construct the lagrangians of N=1 and N=2 pure supergravity in four dimensions with negative cosmological constant, in the presence of a non trivial boundary of space-time. We find that the supersymmetry invariance of the action requires the addition of topological terms which generalize at the supersymmetric level the Gauss-Bonnet term. Supersymmetry invariance is achieved without requiring Dirichlet boundary conditions on the fields at the boundary, rather we find that the boundary values of the fieldstrengths are dynamically fixed to constant values in terms of the cosmological constant Lambda. From a group-theoretical point of view this means in particular the vanishing of the OSp(N|4)-supercurvatures at the boundar
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