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501
Distributions of flux vacua
 JHEP
"... Abstract: We give results for the distribution and number of flux vacua of various types, supersymmetric and nonsupersymmetric, in IIb string theory compactified on CalabiYau manifolds. We compare this with related problems such as counting attractor points. Contents ..."
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Cited by 165 (16 self)
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Abstract: We give results for the distribution and number of flux vacua of various types, supersymmetric and nonsupersymmetric, in IIb string theory compactified on CalabiYau manifolds. We compare this with related problems such as counting attractor points. Contents
Supersymmetry and Attractors
 Phys. Rev. D
, 1996
"... We find a general principle which allows one to compute the area of the horizon of N=2 extremal black holes as an extremum of the central charge. One considers the ADM mass equal to the central charge as a function of electric and magnetic charges and moduli and extremizes this function in the modul ..."
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Cited by 158 (14 self)
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We find a general principle which allows one to compute the area of the horizon of N=2 extremal black holes as an extremum of the central charge. One considers the ADM mass equal to the central charge as a function of electric and magnetic charges and moduli and extremizes this function in the moduli space (a minimum corresponds to a fixed point of attraction). The extremal value of the square of the central charge provides the area of the horizon, which depends only on electric and magnetic charges. The doubling of unbroken supersymmetry at the fixed point of attraction for N=2 black holes near the horizon is derived via conformal flatness of the BertottiRobinsontype geometry. These results provide an explicit model independent expression for the macroscopic BekensteinHawking entropy of N=2 black holes which is manifestly duality invariant. The presence of hypermultiplets in the solution does not affect the area formula. Various examples of the general formula are displayed. We outline the attractor mechanism in N=4,8 supersymmetries and the relation to the N=2 case. The entropyarea formula in five dimensions, recently discussed in the literature, is also seen to be obtained by extremizing the 5d central charge.
de Sitter string vacua from supersymmetric Dterms
 JHEP
, 2003
"... Abstract: We propose a new mechanism for obtaining de Sitter vacua in type IIB string theory compactified on (orientifolded) CalabiYau manifolds similar to those recently studied by Kachru, Kallosh, Linde and Trivedi (KKLT). dS vacuum appears in KKLT model after uplifting an AdS vacuum by adding an ..."
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Cited by 158 (19 self)
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Abstract: We propose a new mechanism for obtaining de Sitter vacua in type IIB string theory compactified on (orientifolded) CalabiYau manifolds similar to those recently studied by Kachru, Kallosh, Linde and Trivedi (KKLT). dS vacuum appears in KKLT model after uplifting an AdS vacuum by adding an antiD3brane, which explicitly breaks supersymmetry. We accomplish the same goal by adding fluxes of gauge fields within the D7branes, which induce a Dterm potential in the effective 4D action. In this way we obtain dS space as a spontaneously broken vacuum from a purely supersymmetric 4D action. We argue that our approach can be directly extended to heterotic string vacua, with the dilaton potential obtained from a combination of gaugino condensation and the Dterms generated by anomalous U(1) gauge groups. 1
Observational signatures and nongaussianities of general single field inflation
"... We perform a general study of primordial scalar nonGaussianities in single field inflationary models in Einstein gravity. We consider models where the inflaton Lagrangian is an arbitrary function of the scalar field and its first derivative, and the sound speed is arbitrary. We find that under reas ..."
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Cited by 157 (10 self)
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We perform a general study of primordial scalar nonGaussianities in single field inflationary models in Einstein gravity. We consider models where the inflaton Lagrangian is an arbitrary function of the scalar field and its first derivative, and the sound speed is arbitrary. We find that under reasonable assumptions, the nonGaussianity is completely determined by 5 parameters. In special limits of the parameter space, one finds distinctive “shapes ” of the nonGaussianity. In models with a small sound speed, several of these shapes would become potentially observable in the near future. Different limits of our formulae recover various previously known results. Contents
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
Flux–induced Soft Supersymmetry Breaking in Chiral Type IIB Orientifolds with D3/D7–Branes
, 2004
"... We discuss supersymmetry breaking via 3–form fluxes in chiral supersymmetric type IIB orientifold vacua with D3 – and D7–branes. After a general discussion of possible choices of fluxes allowing for stabilizing of a part of the moduli, we determine the resulting effective action including all soft s ..."
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Cited by 79 (8 self)
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We discuss supersymmetry breaking via 3–form fluxes in chiral supersymmetric type IIB orientifold vacua with D3 – and D7–branes. After a general discussion of possible choices of fluxes allowing for stabilizing of a part of the moduli, we determine the resulting effective action including all soft supersymmetry breaking terms. We also extend the computation of our previous work [1] concerning the matter field metrics arising from various open string sectors, in particular focusing on the 1/2 BPS D3/D7–brane configuration. Afterwards, the F–theory lift of our constructions is investigated
Distributions of Nonsupersymmetric Flux Vacua
, 2004
"... We continue the study of the distribution of nonsupersymmetric flux vacua in IIb string theory compactified on CalabiYau manifolds, as in hepth/0404116. We show that the basic structure of this problem is that of finding eigenvectors of the matrix of second derivatives of the superpotential, and t ..."
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Cited by 77 (9 self)
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We continue the study of the distribution of nonsupersymmetric flux vacua in IIb string theory compactified on CalabiYau manifolds, as in hepth/0404116. We show that the basic structure of this problem is that of finding eigenvectors of the matrix of second derivatives of the superpotential, and that many features of the results are determined by features of the generic ensemble of such matrices, the CI ensemble of Altland and Zirnbauer originating in mesoscopic physics. We study some simple examples in detail, exhibiting various factors which can favor low or high scale supersymmetry breaking.
Dynamics of warped compactifications and the shape of the warped landscape
, 2005
"... The dynamics of warped/flux compactifications is studied, including warping effects, providing a firmer footing for investigation of the “landscape.” We present a general formula for the fourdimensional potential of warped compactifications in terms of tendimensional quantities. This allows a syste ..."
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Cited by 77 (2 self)
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The dynamics of warped/flux compactifications is studied, including warping effects, providing a firmer footing for investigation of the “landscape.” We present a general formula for the fourdimensional potential of warped compactifications in terms of tendimensional quantities. This allows a systematic investigation of modulifixing effects and potentials for mobile branes. We provide a necessary criterion, “slopedominance, ” for evading “nogo ” results for de Sitter vacua. We outline the tendimensional derivation of the nonperturbative effects that should accomplish this in KKLT examples, and outline a systematic discussion of their corrections. We show that potentials for mobile branes receive generic contributions inhibiting slowroll inflation. We give a linearized analysis of general scalar perturbations of warped IIB compactifications, revealing new features for both time independent and dependent moduli, and new aspects of the kinetic part of the fourdimensional effective action. The universal Kahler modulus is found not to be a simple scaling of the internal metric, and a prescription is given for defining holomorphic Kahler moduli, including warping effects. In the presence of mobile branes, this
Symmetry breaking and axionic strings in the warped deformed conifold
 JHEP 0409
"... We interpret Dstrings at the bottom of the warped deformed conifold as axionic strings in the dual cascading SU(N + M) × SU(N) gauge theory. The axion is a massless pseudoscalar glueball which we find in the supergravity fluctuation spectrum and interpret as the Goldstone boson of spontaneously b ..."
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Cited by 73 (10 self)
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We interpret Dstrings at the bottom of the warped deformed conifold as axionic strings in the dual cascading SU(N + M) × SU(N) gauge theory. The axion is a massless pseudoscalar glueball which we find in the supergravity fluctuation spectrum and interpret as the Goldstone boson of spontaneously broken U(1) baryon number symmetry. The existence of this massless glueball, anticipated in hepth/0101013, supports the idea that the cascading gauge theory is on the baryonic branch, i.e. the U(1)B global symmetry is broken by expectation values of baryonic operators. We also find a massless scalar glueball, which is a superpartner of the pseudoscalar. This scalar mode is a mixture of an NSNS 2form and a metric perturbation of the warped deformed conifold of a type first considered in hepth/0012034.