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Proeyen, FayetIliopoulos terms in supergravity and cosmology
"... We clarify the structure of N = 1 supergravity in 1+3 dimensions with constant Fayet–Iliopoulos (FI) terms. The FI terms gξ induce nonvanishing Rcharges for the fermions and the superpotential. Therefore the Dterm inflation model in supergravity with constant FI terms has to be revisited. We pres ..."
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Cited by 59 (3 self)
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We clarify the structure of N = 1 supergravity in 1+3 dimensions with constant Fayet–Iliopoulos (FI) terms. The FI terms gξ induce nonvanishing Rcharges for the fermions and the superpotential. Therefore the Dterm inflation model in supergravity with constant FI terms has to be revisited. We present all corrections of order gξ/M 2 P to the classical supergravity action required by local supersymmetry and provide a gaugeanomalyfree version of the model. We also investigate the case of the socalled anomalous U(1) when a chiral superfield is shifted under U(1). In such a case, in the context of string theory, the FI terms originate from the derivative of the Kähler potential and they are inevitably fielddependent. This raises an issue of stabilization of the relevant field in applications to cosmology. The recently suggested equivalence between the Dterm strings and Dbranes of type II theory shows that braneantibrane systems produce FI terms in the effective 4d theory, with the RamondRamond axion shifting under the U(1) symmetry. This connection gives the possibility to interpret many unknown properties of D− ¯ D systems in the more familiar language of 4d supergravity Dterms, and vice versa. For instance, the shift of the axion field in both cases restricts the possible
The theory of superstring with flux on nonKahler manifolds and the complex MongeAmpere equation, preprint
"... The purpose of this paper is to solve a problem posed by Strominger in constructing smooth models of superstring theory with flux. These are given by nonKähler manifolds with torsion. 1. ..."
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Cited by 57 (12 self)
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The purpose of this paper is to solve a problem posed by Strominger in constructing smooth models of superstring theory with flux. These are given by nonKähler manifolds with torsion. 1.
Heterotic flux compactifications and their moduli
, 2006
"... We study supersymmetric compactification to four dimensions with nonzero Hflux in heterotic string theory. The background metric is generically conformally balanced and can be conformally Kähler if the primitive part of the Hflux vanishes. Analyzing the linearized variational equations, we write ..."
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Cited by 21 (3 self)
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We study supersymmetric compactification to four dimensions with nonzero Hflux in heterotic string theory. The background metric is generically conformally balanced and can be conformally Kähler if the primitive part of the Hflux vanishes. Analyzing the linearized variational equations, we write down necessary conditions for the existence of moduli associated with the metric. In a heterotic model that is dual to a IIB compactification on an orientifold, we find the metric moduli in a fixed Hflux background via duality and check that they satisfy the required conditions. We also discuss expressing the conditions for moduli in a fixed flux background using twisted differential operators.
In the Realm of the Geometric Transitions
"... We complete the duality cycle by constructing the geometric transition duals in the type IIB, type I and heterotic theories. We show that in the type IIB theory the background on the closed string side is a Kähler deformed conifold, as expected, even though the mirror type IIA backgrounds are nonKä ..."
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Cited by 13 (7 self)
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We complete the duality cycle by constructing the geometric transition duals in the type IIB, type I and heterotic theories. We show that in the type IIB theory the background on the closed string side is a Kähler deformed conifold, as expected, even though the mirror type IIA backgrounds are nonKähler (both before and after the transition). On the other hand, the Type I and heterotic backgrounds are nonKähler. Therefore, on the heterotic side these backgrounds give rise to new torsional manifolds that have not been studied before. We show the consistency of these backgrounds by verifying the torsional equation.
Geometric transitions, flops and nonKähler manifolds: I
, 2004
"... We construct a duality cycle which provides a complete supergravity description of geometric transitions in type II theories via a flop in Mtheory. This cycle connects the different supergravity descriptions before and after the geometric transitions. Our construction reproduces many of the known p ..."
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Cited by 11 (6 self)
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We construct a duality cycle which provides a complete supergravity description of geometric transitions in type II theories via a flop in Mtheory. This cycle connects the different supergravity descriptions before and after the geometric transitions. Our construction reproduces many of the known phenomena studied earlier in the literature and allows us to describe some new and interesting aspects in a simple and elegant fashion. A precise supergravity description of new torsional manifolds that appear on the type IIA side with branes and fluxes and the corresponding geometric transition are obtained. A local description of new G2 manifolds that are circle fibrations over nonKähler manifolds
Hitchin Functionals in N = 2 Supergravity
, 2006
"... We consider type II string theory in spacetime backgrounds which admit eight supercharges. Such backgrounds are characterized by the existence of a (generically nonintegrable) generalized SU(3)×SU(3) structure. We demonstrate how the corresponding tendimensional supergravity theories can in part b ..."
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Cited by 8 (0 self)
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We consider type II string theory in spacetime backgrounds which admit eight supercharges. Such backgrounds are characterized by the existence of a (generically nonintegrable) generalized SU(3)×SU(3) structure. We demonstrate how the corresponding tendimensional supergravity theories can in part be rewritten using generalised O(6, 6)covariant fields, in a form that strongly resembles that of fourdimensional N = 2 supergravity, and precisely coincides with such after an appropriate Kaluza–Klein reduction. Specifically we demonstrate that the NS sector admits a special Kähler geometry with Kähler potentials given by the Hitchin functionals. Furthermore we explicitly compute the N = 2 version of the superpotential from the transformation law of the gravitinos, and find its N = 1 counterpart.
MTheory with Framed Corners and Tertiary Index Invariants
 SYMMETRY, INTEGRABILITY AND GEOMETRY: METHODS AND APPLICATIONS
, 2014
"... The study of the partition function in Mtheory involves the use of index theory on a twelvedimensional bounding manifold. In eleven dimensions, viewed as a boundary, this is given by secondary index invariants such as the Atiyah–Patodi–Singer etainvariant, the Chern–Simons invariant, or the Ada ..."
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Cited by 5 (4 self)
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The study of the partition function in Mtheory involves the use of index theory on a twelvedimensional bounding manifold. In eleven dimensions, viewed as a boundary, this is given by secondary index invariants such as the Atiyah–Patodi–Singer etainvariant, the Chern–Simons invariant, or the Adams einvariant. If the elevendimensional manifold itself has a boundary, the resulting tendimensional manifold can be viewed as a codimension two corner. The partition function in this context has been studied by the author in relation to index theory for manifolds with corners, essentially on the product of two intervals. In this paper, we focus on the case of framed manifolds (which are automatically Spin) and provide a formulation of the refined partition function using a tertiary index invariant, namely the finvariant introduced by Laures within elliptic cohomology. We describe the context globally, connecting the various spaces and theories around Mtheory, and providing a physical realization and interpretation of some ingredients appearing in the constructions due to Bunke–Naumann and Bodecker. The formulation leads to a natural interpretation of anomalies using corners and uncovers some resulting constraints in the heterotic corner. The analysis for type IIA leads to a physical identification of various components of etaforms appearing in the formula for the phase of the partition function.