Results 1  10
of
53
Magnetic monopoles, duality, and supersymmetry
"... These notes present a pedagogical introduction to magnetic monopoles and exact electromagnetic duality in supersymmetric gauge theories. They are based on lectures given at the 1995 Trieste Summer School in High Energy Physics and Cosmology and at ..."
Abstract

Cited by 54 (1 self)
 Add to MetaCart
(Show Context)
These notes present a pedagogical introduction to magnetic monopoles and exact electromagnetic duality in supersymmetric gauge theories. They are based on lectures given at the 1995 Trieste Summer School in High Energy Physics and Cosmology and at
Heterotic Moduli Stabilization with Fractional ChernSimons Invariants
 MODULI STABILIZATION IN THE HETEROTIC/IIB DISCRETUUM
, 2004
"... We show that fractional flux from Wilson lines can stabilize the moduli of heterotic string compactifications on CalabiYau threefolds. We observe that the Wilson lines used in GUT symmetry breaking naturally induce a fractional flux. When combined with a hiddensector gaugino condensate, this gener ..."
Abstract

Cited by 36 (0 self)
 Add to MetaCart
(Show Context)
We show that fractional flux from Wilson lines can stabilize the moduli of heterotic string compactifications on CalabiYau threefolds. We observe that the Wilson lines used in GUT symmetry breaking naturally induce a fractional flux. When combined with a hiddensector gaugino condensate, this generates a potential for the complex structure moduli, Kähler moduli, and dilaton. This potential has a supersymmetric AdS minimum at moderately weak coupling and large volume. Notably, the necessary ingredients for this construction are often present in realistic models. We explore the type IIA dual phenomenon, which involves Wilson lines in D6branes wrapping a threecycle in a CalabiYau, and comment on the nature of the fractional instantons which change the ChernSimons invariant.
Compactifications of heterotic strings on nonKähler complex manifolds
 II,” Nucl. Phys. B
"... We continue our study of heterotic compactifications on nonKähler complex manifolds with torsion. We give further evidence of the consistency of the sixdimensional manifold presented earlier and discuss the anomaly cancellation and possible supergravity description for a generic nonKähler complex ..."
Abstract

Cited by 30 (11 self)
 Add to MetaCart
(Show Context)
We continue our study of heterotic compactifications on nonKähler complex manifolds with torsion. We give further evidence of the consistency of the sixdimensional manifold presented earlier and discuss the anomaly cancellation and possible supergravity description for a generic nonKähler complex manifold using the newly proposed superpotential. The manifolds studied in our earlier papers had zero Euler characteristics. We construct new examples of nonKähler complex manifolds with torsion in lower dimensions, that have nonzero Euler characteristics. Some of these examples are constructed from consistent backgrounds in Ftheory and therefore are solutions to the string equations of motion. We discuss consistency conditions for compactifications of the heterotic string on smooth nonKähler manifolds and illustrate how some results well known for CalabiYau compactifications, including counting the number of generations, apply to the nonKähler case. We briefly address various issues regarding possible phenomenological
IIA string theory on CalabiYau fourfolds with background fluxes
 Nucl. Phys. B
"... Looking for string vacua with fixed moduli, we study compactifications of type IIA string theory on CalabiYau fourfolds in the presence of generic RamondRamond fields. We explicitly derive the (super)potential induced by RamondRamond fluxes performing a KaluzaKlein reduction of the tendimension ..."
Abstract

Cited by 28 (2 self)
 Add to MetaCart
Looking for string vacua with fixed moduli, we study compactifications of type IIA string theory on CalabiYau fourfolds in the presence of generic RamondRamond fields. We explicitly derive the (super)potential induced by RamondRamond fluxes performing a KaluzaKlein reduction of the tendimensional effective action. This can be conveniently achieved in a formulation of the massive type IIA supergravity where all RamondRamond fields appear in a democratic way. The result agrees with the general formula for the superpotential written in terms of calibrations. We further notice that for generic RamondRamond fluxes all geometric moduli are stabilized and one finds nonsupersymmetric vacua at positive values of the scalar potential. March
Fluxinduced SUSYbreaking soft terms
 Nucl. Phys. B 689
"... We describe the computation of SUSYbreaking terms on a D3brane in a quite general type IIB supergravity background. We apply it to study the SUSYbreaking induced on the D3brane worldvolume by the presence of NSNS and RR 3form fluxes. We provide explicit general formulae for the SUSYbreaking so ..."
Abstract

Cited by 23 (6 self)
 Add to MetaCart
(Show Context)
We describe the computation of SUSYbreaking terms on a D3brane in a quite general type IIB supergravity background. We apply it to study the SUSYbreaking induced on the D3brane worldvolume by the presence of NSNS and RR 3form fluxes. We provide explicit general formulae for the SUSYbreaking soft terms valid for the different types of fluxes, leading to different patterns of soft terms. Imaginary anti selfdual fluxes with G3 a pure (3,0)form lead to soft terms corresponding to dilatondominated SUSYbreaking. More general SUSYbreaking patterns are discussed, arising from more general fluxes, or from distant antiD3branes. The known finiteness properties of dilatondominated soft terms are understood in terms of holography. The above results are interpreted in the context of the 4d effective supergravity theory, where flux components correspond to auxiliary fields of e.g. the 4d dilaton and overall volume modulus. We present semirealistic Type IIB orientifold examples with (meta)stable vacua leading to nonvanishing soft terms of the dilatondomination type. Such models have many of the ingredients of the
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 ..."
Abstract

Cited by 21 (3 self)
 Add to MetaCart
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.
Supersymmetry breaking and α ′ −corrections to flux induced potentials, JHEP 0206
, 2002
"... We obtain the vacuum solutions for Mtheory compactified on eightmanifolds with nonvanishing fourform flux by analyzing the scalar potential appearing in the threedimensional theory. Many of these vacua are not supersymmetric and yet have a vanishing threedimensional cosmological constant. We sh ..."
Abstract

Cited by 20 (3 self)
 Add to MetaCart
(Show Context)
We obtain the vacuum solutions for Mtheory compactified on eightmanifolds with nonvanishing fourform flux by analyzing the scalar potential appearing in the threedimensional theory. Many of these vacua are not supersymmetric and yet have a vanishing threedimensional cosmological constant. We show that in the context of Type IIB compactifications on CalabiYau threefolds with fluxes and external brane sources α ′corrections generate a correction to the supergravity potential proportional to the Euler number of the internal manifold which spoils the noscale structure appearing in the classical potential. This indicates that α ′corrections may indeed lead to a stabilization of the radial modulus appearing in these compactifications. April
ANALYTIC TORSION FOR TWISTED DE RHAM COMPLEXES
, 2008
"... We define analytic torsion τ(X, E, H) ∈ detH • (X, E,H) for the twisted de Rham complex, consisting of differential forms on a compact Riemannian manifold X valued in a flat vector bundle E, with a differential given by ∇ E + H ∧ ·, where ∇ E is a flat connection on E, H is an odddegree closed di ..."
Abstract

Cited by 18 (3 self)
 Add to MetaCart
We define analytic torsion τ(X, E, H) ∈ detH • (X, E,H) for the twisted de Rham complex, consisting of differential forms on a compact Riemannian manifold X valued in a flat vector bundle E, with a differential given by ∇ E + H ∧ ·, where ∇ E is a flat connection on E, H is an odddegree closed differential form on X, and H • (X, E,H) denotes the cohomology of this Z2graded complex. We show that when dimX is odd, τ(X, E,H) is independent of the choice of metrics on X and E and of the representative H in the cohomology class [H]. We also explain the relation to generalized geometry. We establish some basic functorial properties and, when H is a topdegree form, compute the torsion and relate it to a simplicial analogue. We also establish the relationship of an invariant form of the analytic torsion for Tdual circle bundles with 3form fluxes.
Loop groups, KaluzaKlein reduction and Mtheory
 J. High Energy Phys
"... We show that the data of a principal G bundle over a principal circle bundle is equivalent to that of a ̂ LG def = U(1) ⋉ LG bundle over the base of the circle bundle. We apply this to the KaluzaKlein reduction of Mtheory to IIA and show that certain generalized characteristic classes of the loop ..."
Abstract

Cited by 10 (0 self)
 Add to MetaCart
(Show Context)
We show that the data of a principal G bundle over a principal circle bundle is equivalent to that of a ̂ LG def = U(1) ⋉ LG bundle over the base of the circle bundle. We apply this to the KaluzaKlein reduction of Mtheory to IIA and show that certain generalized characteristic classes of the loop group bundle encode the Bianchi identities of the antisymmetric tensor fields of IIA supergravity. We further show that the low dimensional characteristic classes of the central extension of the loop group encode the Bianchi identities of massive IIA, thereby adding support to the conjectures of hepth/0203218. 1. Introduction and Summary It has long been established that IIA supergravity is the dimensional reduction of the unique theory of supergravity in eleven dimensions. We have learned in the last decade, however, that eleven dimensional supergravity is the low energy limit of a still mysterious theory termed Mtheory and that the KaluzaKlein reduction of this theory is the ten dimensional