22 research outputs found
Matter Coupled F(4) Supergravity and the AdS_6/CFT_5 Correspondence
F(4) supergravity, the gauge theory of the exceptional six-dimensional
Anti-de Sitter superalgebra, is coupled to an arbitrary number of vector
multiplets whose scalar components parametrize the quaternionic manifold
. By gauging the compact subgroup SU(2)_d \otimes
\cG, where SU(2)_d is the diagonal subgroup of (the R-symmetry group of six-dimensional Poincar\'e supergravity) and
\cG is a compact group such that dim\cG = n, we compute the scalar
potential which, besides the gauge coupling constants, also depends in non
trivial way on the parameter m associated to a massive 2-form of
the gravitational multiplet. The potential admits an AdS background for g=3m,
as the pure F(4)-supergravity. We compute the scalar squared masses (which are
all negative) and retrieve the results dictated by AdS_6/CFT_5 correspondence
from the conformal dimensions of boundary operators. The boundary F(4)
superconformal fields are realized in terms of a singleton superfield
(hypermultiplet) in harmonic superspace with flag manifold SU(2)/U(1)=S^2. We
analize the spectrum of short representations in terms of superconformal
primaries and predict general features of the K-K specrum of massive type IIA
supergravity compactified on warped .Comment: 21 pages, latex, minor corrections and reference adde
Supersymmetric N=2 Einstein-Yang-Mills monopoles and covariant attractors
We present two generic classes of supersymmetric solutions of N=2, d=4
supergravity coupled to non-Abelian vector supermultiplets with a gauge group
that includes an SU(2) factor. The first class consists of embeddings of the 't
Hooft-Polyakov monopole and in the examples considered it has a fully regular,
asymptotically flat space-time metric without event horizons. The other class
of solutions consists of regular non-Abelian extreme black holes. There is a
covariant attractor at the horizon of these non-Abelian black holes.Comment: 14 pages, Late
On the construction of variant supergravities in D=11, D=10
We construct with a geometric procedure the supersymmetry transformation laws
and Lagrangian for all the ``variant'' D=11 and D=10 Type IIA supergravities.
We identify into our classification the D=11 and D=10 Type IIA ``variant''
theories first introduced by Hull performing T-duality transformation on both
spacelike and timelike circles. We find in addition a set of D=10 Type IIA
``variant'' supergravities that can not be obtained trivially from eleven
dimensions compactifying on a circle.Comment: 21 pages, Late
Gauging the Heisenberg algebra of special quaternionic manifolds
We show that in N=2 supergravity, with a special quaternionic manifold of
(quaternionic) dimension h_1+1 and in the presence of h_2 vector multiplets, a
h_2+1 dimensional abelian algebra, intersecting the 2h_1+3 dimensional
Heisenberg algebra of quaternionic isometries, can be gauged provided the h_2+1
symplectic charge--vectors V_I, have vanishing symplectic invariant scalar
product V_I X V_J=0. For compactifications on Calabi--Yau three--folds with
Hodge numbers (h_1,h_2) such condition generalizes the half--flatness condition
as used in the recent literature. We also discuss non--abelian extensions of
the above gaugings and their consistency conditions.Comment: 9 pages, LaTe
D=6, N=2, F(4)-Supergravity with supersymmetric de Sitter Background
We show that there exists a supersymmetric de Sitter background for the D=6,
N=2, F(4) supergravity preserving the compact R-symmetry and gauging with
respect to the conventional Anti de Sitter version of the theory. We construct
the gauged matter coupled F(4) de Sitter supergravity explicitly and show that
it contains ghosts in the vector sector.Comment: 19 pages, Late
On the underlying E11 symmetry of the D=11 Free Differential Algebra
We study the reduction of the Free Differential Algebra (FDA) of D=11
supergravity to an ordinary algebra. We show that in flat background and with
vanishing three-form field strength, the corresponding minimal FDA can be
reduced to an Inonu-Wigner contraction of Sezgin's M-Algebra. We also prove
that in flat background but with a non trivial three-form field strength, the
bosonic FDA can be reduced to the lowest levels of E11. This result suggests
that the E11 symmetries, which act on perturbative states as well, are already
encoded in the D=11 FDA and are made explicit when the theory is formulated on
a enlarged group manifold.Comment: 25 pages, LaTeX, typos corrected, final version published in JHE
N=4 supergravity for Type IIB on T^6/Z_2 in presence of fluxes
We report on the construction of four dimensional gauged supergravity models
that can be interpreted as type IIB orientifold compactification in presence of
3-form fluxes and D3--branes. We mainly address our attention to the symplectic
embedding of the U-duality group of the theory and the consequent choice of the
gauge group, whose four dimensional killing vectors are the remnant of the ten
dimensional fluxes. We briefly discuss the structure of the scalar potential
arising from the gauging and the properties of the killing vectors in order to
preserve some amount of supersymmetry.Comment: LaTeX, iopart class, 9 pages, Contribution to the proceedings of the
workshop of the RTN Network "The quantum structure of space-time and the
geometric nature of fundamental interactions",Copenhagen, September 2003 2nd
version, references adde
Scalar potential for the gauged Heisenberg algebra and a non-polynomial antisymmetric tensor theory
We study some issues related to the effective theory of Calabi-Yau
compactifications with fluxes in Type II theories. At first the scalar
potential for a generic electric abelian gauging of the Heisenberg algebra,
underlying all possible gaugings of RR isometries, is presented and shown to
exhibit, in some circumstances, a "dual'' no-scale structure under the
interchange of hypermultiplets and vector multiplets. Subsequently a new
setting of such theories, when all RR scalars are dualized into antisymmetric
tensors, is discussed. This formulation falls in the class of non-polynomial
tensor theories considered long ago by Freedman and Townsend and it may be
relevant for the introduction of both electric and magnetic charges.Comment: 11 pages LaTe
No-scale N=4 supergravity coupled to Yang-Mills: the scalar potential and super-Higgs effect
We derive the scalar potential of the effective theory of type
IIB orientifold with 3-form fluxes turned on in presence of non abelian brane
coordinates. N=4 supergravity predicts a positive semidefinite potential with
vanishing cosmological constant in the vacuum of commuting coordinates, with a
classical moduli space given by three radial moduli and three RR scalars which
complete three copies of the coset (U(1,1+n)/U(1)\otimes U(1+n)), together with
6n D3-branes coordinates, n being the rank of the gauge group G. Implications
for the super Higgs mechanism are also discussed.Comment: misprints correcte
N=4 gauged supergravity and a IIB orientifold with fluxes
We analyze the properties of a spontaneously broken D=4, N=4 supergravity
without cosmological constant, obtained by gauging translational isometries of
its classical scalar manifold. This theory offers a suitable low energy
description of the super-Higgs phases of certain Type-IIB orientifold
compactifications with 3-form fluxes turned on. We study its N=3,2,1,0 phases
and their classical moduli spaces and we show that this theory is an example of
no-scale extended supergravity.Comment: Misprints corrected. Version appeared on NJP 4 (2002)7