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45
Fourdimensional String Compactifications with DBranes, Orientifolds and Fluxes
"... This review article provides a pedagogical introduction into various classes of chiral string compactifications to four dimensions with Dbranes and fluxes. The main concern is to provide all necessary technical tools to explicitly construct fourdimensional orientifold vacua, with the final aim to ..."
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Cited by 147 (18 self)
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This review article provides a pedagogical introduction into various classes of chiral string compactifications to four dimensions with Dbranes and fluxes. The main concern is to provide all necessary technical tools to explicitly construct fourdimensional orientifold vacua, with the final aim to come as close as possible to the supersymmetric Standard Model. Furthermore, we outline the available methods to derive the resulting fourdimensional effective action. Finally, we summarize recent attempts to address the
Largevolume flux compactifications: Moduli spectrum and D3/D7 soft supersymmetry breaking
 SYSTEMATICS OF MODULI STABILISATION IN CALABIYAU FLUX COMPACTIFICATIONS,” JHEP 0503 (2005) 007 [ARXIV:HEPTH/0502058]. – 42
, 2005
"... We present an explicit calculation of the spectrum of a general class of string models, corresponding to CalabiYau flux compactifications with h1,2> h1,1> 1 with leading perturbative and nonperturbative corrections, in which all geometric moduli are stabilised as in hepth/0502058. The volum ..."
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Cited by 129 (20 self)
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We present an explicit calculation of the spectrum of a general class of string models, corresponding to CalabiYau flux compactifications with h1,2> h1,1> 1 with leading perturbative and nonperturbative corrections, in which all geometric moduli are stabilised as in hepth/0502058. The volume is exponentially large, leading to a range of string scales from the Planck mass to the TeV scale, realising for the first time the large extra dimensions scenario in string theory. We provide a general analysis of the relevance of perturbative and nonperturbative effects and the regime of validity of the effective field theory. We compute the spectrum in the moduli sector finding a hierarchy of masses depending on inverse powers of the volume. We also compute soft supersymmetry breaking terms for particles living on D3 and D7 branes. We find a hierarchy of soft terms corresponding to ‘volume dominated ’ Fterm supersymmetry breaking. Fterms for Kähler moduli dominate both those for dilaton and complex
An open string landscape
 JHEP
, 2005
"... Abstract: The effect of fluxes on open string moduli is studied by analyzing the constraints imposed by supersymmetry on Dbranes in type IIB flux backgrounds. We show that generically the conditions of supersymmetry cannot be maintained when moving along the geometrical moduli space of the brane, s ..."
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Cited by 56 (3 self)
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Abstract: The effect of fluxes on open string moduli is studied by analyzing the constraints imposed by supersymmetry on Dbranes in type IIB flux backgrounds. We show that generically the conditions of supersymmetry cannot be maintained when moving along the geometrical moduli space of the brane, so that open string moduli are lifted. In specific examples, we find that there is a disconnected and discrete set of supersymmetric solutions to the open string equations of motion, which extends the familiar closed string landscape to the open string sector. Permanent addressContents
Jumping Through Loops: On Soft Terms from Large Volume Compactifications
 JHEP
, 2007
"... We subject the phenomenologically successful large volume scenario of hepth/0502058 to a first consistency check in string theory. In particular, we consider whether the expansion of the string effective action is consistent in the presence of Dbranes and Oplanes. Due to the noscale structure at ..."
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Cited by 41 (0 self)
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We subject the phenomenologically successful large volume scenario of hepth/0502058 to a first consistency check in string theory. In particular, we consider whether the expansion of the string effective action is consistent in the presence of Dbranes and Oplanes. Due to the noscale structure at treelevel, the scenario is surprisingly robust. We compute the modification of soft supersymmetry breaking terms, and find only subleading corrections. We also comment that for largevolume limits of toroidal orientifolds and fibered CalabiYau manifolds the corrections can be more important,
String loop corrections to Kähler potentials
 in orientifolds,” JHEP 0511 (2005) 030 [arXiv:hepth/0508043
"... We determine oneloop string corrections to Kähler potentials in type IIB orientifold compactifications with either N = 1 or N = 2 supersymmetry, including Dbrane ..."
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Cited by 27 (4 self)
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We determine oneloop string corrections to Kähler potentials in type IIB orientifold compactifications with either N = 1 or N = 2 supersymmetry, including Dbrane
Hints for OffShell Mirror Symmetry in type II/Ftheory Compactifications
, 2009
"... We perform a Hodge theoretic study of parameter dependent families of Dbranes on compact Calabi–Yau manifolds in type II and Ftheory compactifications. Starting from a geometric GaussManin connection for B type branes we study the integrability and flatness conditions. The B model geometry define ..."
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Cited by 24 (4 self)
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We perform a Hodge theoretic study of parameter dependent families of Dbranes on compact Calabi–Yau manifolds in type II and Ftheory compactifications. Starting from a geometric GaussManin connection for B type branes we study the integrability and flatness conditions. The B model geometry defines an interesting ring structure of operators. For the mirror A model this indicates the existence of an openstring extension of the socalled A model connection, whereas the discovered ring structure should be part of the openstring A model quantum cohomology. We obtain predictions for genuine OoguriVafa invariants for Lagrangian branes on the quintic in P 4 that pass some nontrivial consistency checks. We discuss the lift of the brane compactifications to Ftheory on Calabi–Yau 4folds and the effective couplings in the effective supergravity action as determined by the N = 1 special geometry of the openclosed deformation space.
On the supergravity formulation of mirror symmetry in generalized CalabiYau manifolds
, 2007
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On volume stabilization by quantum corrections
"... We discuss prospects for stabilizing the volume modulus of N = 1 supersymmetric type IIB orientifold compactifications using only perturbative corrections to the Kähler potential. Concretely, we consider the known string loop corrections and treelevel α ′ corrections. They break the noscale struct ..."
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Cited by 17 (3 self)
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We discuss prospects for stabilizing the volume modulus of N = 1 supersymmetric type IIB orientifold compactifications using only perturbative corrections to the Kähler potential. Concretely, we consider the known string loop corrections and treelevel α ′ corrections. They break the noscale structure of the potential, which otherwise prohibits stabilizing the volume modulus. We argue that when combined, these corrections provide enough flexibility to stabilize the volume of the internal space without nonperturbative effects, although we are not able to present a completely explicit example within the limited set of currently available models. Furthermore, a certain amount of In a companion paper [1] we computed oneloop corrections to the Kähler potentials of certain supersymmetric orientifolds of type IIB string theory. Here, we interpret these results in the context of volume stabilization. The two papers can be read independently.
Membrane instantons and de Sitter vacua
 JHEP 0509 (2005) 065, hepth/0506097. 33 D. Tong, NS5branes, Tduality and worldsheet instantons, JHEP 0207:013
, 2002
"... We investigate membrane instanton effects in type IIA strings compactified on rigid CalabiYau manifolds. These effects contribute to the lowenergy effective action of the universal hypermultiplet. In the absence of additional fivebrane instantons, the quaternionic geometry of this hypermultiplet i ..."
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Cited by 11 (3 self)
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We investigate membrane instanton effects in type IIA strings compactified on rigid CalabiYau manifolds. These effects contribute to the lowenergy effective action of the universal hypermultiplet. In the absence of additional fivebrane instantons, the quaternionic geometry of this hypermultiplet is determined by solutions of the threedimensional Toda equation. We construct solutions describing membrane instantons, and find perfect agreement with the string theory prediction. In the context of flux compactifications we discuss how membrane instantons contribute to the scalar potential and the stabilization of moduli. Finally, we demonstrate the existence of metastable de Sitter vacua. 1