2,594 research outputs found
AdS 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 supergravity with dyonic ISO(7) gauging. These formulae are then used to
construct AdS solutions of massive type IIA via uplift on of the
critical points of the supergravity with at least SU(3) symmetry. We find
a new 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--invariant solution is found to be stable.Comment: 30 pages; v2: a few typos corrected and reference added; v3: A few
clarifications and reference added. Version published in JHEP03(2016)07
Dyonic ISO(7) supergravity and the duality hierarchy
Motivated by its well defined higher dimensional origin, a detailed study of
supergravity with a dyonically gauged gauge group is performed. We write down
the Lagrangian and describe the tensor and duality hierarchies, focusing on an
interesting subsector with closed field equations and supersymmetry
transformations. We then truncate the theory to some smaller
sectors with and supersymmetry and SU(3),
and SO(4) bosonic symmetry. Canonical and superpotential
formulations for these sectors are given, and their vacuum structure and
spectra is analysed. Unlike the purely electric ISO(7) gauging, the dyonic
gauging displays a rich structure of vacua, all of them AdS. We recover all
previously known ones and find a new vacuum with SU(3) symmetry
and various non-supersymmetric vacua, all of them stable within the full
theory.Comment: 52 pages, 4 tables. v2: Section 2.4 on critical points added. v3:
Version published in JHE
Universal Kaluza-Klein reductions of type IIB to N=4 supergravity in five dimensions
We construct explicit consistent Kaluza-Klein reductions of type IIB
supergravity on HK_4 x S^1, where HK_4 is an arbitrary four-dimensional
hyper-Kaehler manifold, and on SE5, an arbitrary five-dimensional
Sasaki-Einstein manifold. In the former case we obtain the bosonic action of
D=5 N=4 (ungauged) supergravity coupled to two vector multiplets. For the SE_5
case we extend a known reduction, which leads to minimal D=5 N=2 gauged
supergravity, to also include a multiplet of massive fields, containing the
breathing mode of the SE_5. We show that the resulting D=5 action is also
consistent with N=4 gauged supergravity coupled to two vector multiplets. This
theory has a supersymmetric AdS_5 vacuum, which uplifts to the class of
supersymmetric AdS_5 x SE_5 solutions, that spontaneously breaks N=4 to N=2,
and also a non-supersymmetric AdS_5 vacuum which uplifts to a class of
solutions first found by Romans.Comment: 1+34 pages. v2: Minor typos corrected, three references added.
Version to be published in JHE
IIB Supergravity and the E6(6) covariant vector-tensor hierarchy
IIB supergravity is reformulated with a manifest local USp(8) invariance that
makes the embedding of five-dimensional maximal supergravities transparent. In
this formulation the ten-dimensional theory exhibits all the 27 one-form fields
and 22 of the 27 two-form fields that are required by the vector-tensor
hierarchy of the five-dimensional theory. The missing 5 two-form fields must
transform in the same representation as a descendant of the ten-dimensional
`dual graviton'. The invariant E6(6) symmetric tensor that appears in the
vector-tensor hierarchy is reproduced. Generalized vielbeine are derived from
the supersymmetry transformations of the vector fields, as well as consistent
expressions for the USp(8) covariant fermion fields. Implications are discussed
for the consistency of the truncation of IIB supergravity compactified on the
five-sphere to maximal gauged supergravity in five space-time dimensions with
an SO(6) gauge group.Comment: 48 pages, added an extra affiliatio
Symmetry and holonomy in M Theory
In this PhD Thesis, supersymmetry and its formulation in the context of D=11
supergravity is discussed from several perspectives. The role of generalized
holonomy as a classification tool of supersymmetric supergravity solutions is
reviewed, with particular emphasis on how successive supercovariant derivatives
of the generalized curvature may be needed to properly define the generalized
holonomy algebra. The generalized curvature is also shown to contain the
supergravity equations of motion, even in the non-vanishing gravitino case. The
underlying gauge symmetry of D=11 supergravity is discussed and argued to
become manifest when its three-form field A_3 is expressed through a set of
one-form gauge fields, associated with the generators of a suitable family of
enlarged supersymmetry algebras. This family is related to osp(1|32) through
expansion, a method to obtain new Lie (super)algebras of increasing dimensions
from given ones. The analysis of the underlying gauge symmetry of D=11
supergravity leads naturally to enlarged supersymmetry algebras and superspaces
making, thus, natural to consider actions for objects moving in such spaces. In
particular, a string moving in tensorial space is discussed, describing the
excitations of a state preserving 30 out of 32 supersymmetries (hence composed
of two preons, hypothetical constituents of M Theory preserving 31
supersymmetries). A G-frame method is also discussed to study hypothetical
preonic solutions of supergravity.Comment: PhD Thesis (Advisor: J.A. de Azcarraga). 16+201 page
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