373 research outputs found
Action for IIB Supergravity in 10 dimensions
We review the construction of a manifestly covariant, supersymmetric and
SL(2R) invariant action for IIB supergravity in D=10.Comment: 9 pages, LaTeX, Talk given at "Quantum Aspects of Gauge Theories,
Supersymmetry and Unification", Greece, September 199
Open-Closed String Duality from Orbifolded Conifolds
We study large N dualities for a class of theories realized on
type IIB D5 branes wrapping 2-cycles of local Calabi-Yau threefolds which is
obtained from resolving orbifolded conifolds or as effective field theories on
D4 branes in type IIA brane configurations. The field theory is supersymmetric Yang-Mills gauge theory. Strong coupling
effects are analyzed in the deformed geometry. We propose open-closed string
duality via a geometric transition in toric geometry. The T-dual type IIA
picture and M-theory lifting are also considered.Comment: arXiv admin note: text overlap with arXiv:hep-th/0105066 by other
author
Flux compactifications in string theory: a comprehensive review
We present a pedagogical overview of flux compactifications in string theory,
from the basic ideas to the most recent developments. We concentrate on closed
string fluxes in type II theories. We start by reviewing the supersymmetric
flux configurations with maximally symmetric four-dimensional spaces. We then
discuss the no-go theorems (and their evasion) for compactifications with
fluxes. We analyze the resulting four-dimensional effective theories, as well
as some of its perturbative and non-perturbative corrections, focusing on
moduli stabilization. Finally, we briefly review statistical studies of flux
backgrounds.Comment: 85 pages, 2 figures. v2, v3: minor changes, references adde
Flux moduli stabilisation, Supergravity algebras and no-go theorems
We perform a complete classification of the flux-induced 12d algebras
compatible with the set of N=1 type II orientifold models that are T-duality
invariant, and allowed by the symmetries of the T^6/(Z_2 x Z_2) isotropic
orbifold. The classification is performed in a type IIB frame, where only H_3
and Q fluxes are present. We then study no-go theorems, formulated in a type
IIA frame, on the existence of Minkowski/de Sitter (Mkw/dS) vacua. By deriving
a dictionary between the sources of potential energy for the three moduli (S, T
and U) in types IIA and IIB, we are able to combine algebra results and no-go
theorems. The outcome is a systematic procedure for identifying
phenomenologically viable models where Mkw/dS vacua may exist. We present a
complete table of the allowed algebras and the viability of their resulting
scalar potential, and we point at the models which stand any chance of
producing a fully stable vacuum.Comment: Version published in JHE
On the sigma-model structure of type IIA supergravity action in doubled field approach
In this letter we describe how to string together the doubled field approach
by Cremmer, Julia, Lu and Pope with Pasti-Sorokin-Tonin technique to construct
the sigma-model-like action for type IIA supergravity. The relation of the
results with that of obtained in the context of searching for
Superstring/M-theory hidden symmetry group is discussed.Comment: 9 pp, LATEX; published in JETP Let
Twistor Approach to String Compactifications: a Review
We review a progress in obtaining the complete non-perturbative effective
action of type II string theory compactified on a Calabi-Yau manifold. This
problem is equivalent to understanding quantum corrections to the metric on the
hypermultiplet moduli space. We show how all these corrections, which include
D-brane and NS5-brane instantons, are incorporated in the framework of the
twistor approach, which provides a powerful mathematical description of
hyperkahler and quaternion-Kahler manifolds. We also present new insights on
S-duality, quantum mirror symmetry, connections to integrable models and
topological strings.Comment: 99 pages; minor corrections; journal versio
Some Cubic Couplings in Type IIB Supergravity on and Three-point Functions in SYM_4 at Large N
All cubic couplings in type IIB supergravity on that
involve two scalar fields that are mixtures of the five form field
strength on and the trace of the graviton on are derived by using
the covariant equations of motion and the quadratic action for type IIB
supergravity on . All corresponding three-point functions in
SYM are calculated in the supergravity approximation. It is pointed out
that the scalars correspond not to the chiral primary operators in the
SYM but rather to a proper extension of the operators.Comment: Latex, 24p, misprints are correcte
Exceptional Flux Compactifications
We consider type II (non-)geometric flux backgrounds in the absence of brane
sources, and construct their explicit embedding into maximal gauged D=4
supergravity. This enables one to investigate the critical points, mass spectra
and gauge groups of such backgrounds. We focus on a class of type IIA geometric
vacua and find a novel, non-supersymmetric and stable AdS vacuum in maximal
supergravity with a non-semisimple gauge group. Our construction relies on a
non-trivial mapping between SL(2) x SO(6,6) fluxes, SU(8) mass spectra and
gaugings of E7(7) subgroups.Comment: 51 pages, 2 figures and 4 tables. v3: change of SO(6,6) spinorial
conventions, published versio
Diagrammar and metamorphosis of coset symmetries in dimensionally reduced type IIB supergravity
Studying the reduction of type IIB supergravity from ten to three space-time
dimensions we describe the metamorphosis of Dynkin diagram for gravity line
"caterpillar" into a type IIB supergravity "dragonfly" that is triggered by
inclusion of scalars and antisymmetric tensor fields. The final diagram
corresponds to type IIB string theory E8 global symmetry group which is the
subgroup of the conjectured E11 hidden symmetry group. Application of the
results for getting the type IIA/IIB T-duality rules and for searching for type
IIB vacua solutions is considered.Comment: 9 pp, 7 figs, LATEX; to be published in JETP Let
- …