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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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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
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.
MODELS OF PARTICLE PHYSICS FROM TYPE IIB STRING THEORY AND FTHEORY: A REVIEW
, 2012
"... We review particle physics model building in type IIB string theory and Ftheory. This is a region in the landscape where in principle many of the key ingredients required for a realistic model of particle physics can be combined successfully. We begin by reviewing moduli stabilisation within this f ..."
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Cited by 33 (4 self)
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We review particle physics model building in type IIB string theory and Ftheory. This is a region in the landscape where in principle many of the key ingredients required for a realistic model of particle physics can be combined successfully. We begin by reviewing moduli stabilisation within this framework and its implications for supersymmetry breaking. We then review model building tools and developments in the weakly coupled type IIB limit, for both local D3branes at singularities and global models of intersecting D7branes. Much of recent model building work has been in the strongly coupled regime of Ftheory due to the presence of exceptional symmetries which allow for the construction of phenomenologically appealing Grand Unified Theories. We review both local and global Ftheory model building starting from the fundamental concepts and tools regarding how the gauge group, matter sector and operators arise, and ranging to detailed phenomenological properties explored in the literature.
Random polynomials and the friendly landscape
"... In hepth/0501082, a field theoretic “toy model ” for the Landscape was proposed. We show that the considerations of that paper carry through to realistic effective Lagrangians, such as those that emerge out of string theory. Extracting the physics of the large number of metastable vacua that ensue ..."
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Cited by 9 (0 self)
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In hepth/0501082, a field theoretic “toy model ” for the Landscape was proposed. We show that the considerations of that paper carry through to realistic effective Lagrangians, such as those that emerge out of string theory. Extracting the physics of the large number of metastable vacua that ensue requires somewhat more sophisticated algebrogeometric techniques, which we review
Explicit de Sitter Flux Vacua for Global String Models with Chiral Matter
"... We address the open question of performing an explicit stabilisation of all closed string moduli (including dilaton, complex structure and Kähler moduli) in fluxed type IIB CalabiYau compactifications with chiral matter. Using toric geometry we construct CalabiYau manifolds with del Pezzo singula ..."
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Cited by 5 (3 self)
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We address the open question of performing an explicit stabilisation of all closed string moduli (including dilaton, complex structure and Kähler moduli) in fluxed type IIB CalabiYau compactifications with chiral matter. Using toric geometry we construct CalabiYau manifolds with del Pezzo singularities. Dbranes located at such singularities can support the Standard Model gauge group and matter content. In order to control complex structure moduli stabilisation we consider CalabiYau manifolds which exhibit a discrete symmetry that reduces the effective number of complex structure moduli. We calculate the corresponding periods in the symplectic basis of invariant threecycles and find explicit flux vacua for concrete examples. We compute the values of the flux superpotential and the string coupling at these vacua. Starting from these explicit complex structure solutions, we obtain AdS and dS minima where the Kähler moduli are stabilised by a mixture of Dterms, nonperturbative and perturbative α ′ corrections as in the LARGE Volume Scenario. In the considered example the visible sector lives at a dP6 singularity which can be higgsed to the phenomenologically interesting class of models at the dP3 singularity. ar X iv
Inflationary de Sitter Solutions
, 706
"... In the framework of superstring compactifications with N = 1 supersymmetry spontaneously broken, (by either geometrical fluxes, branes or else), we show the existence of new inflationary solutions. The timetrajectory of the scale factor of the metric a, the supersymmetry breaking scale m ≡ m(Φ) and ..."
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In the framework of superstring compactifications with N = 1 supersymmetry spontaneously broken, (by either geometrical fluxes, branes or else), we show the existence of new inflationary solutions. The timetrajectory of the scale factor of the metric a, the supersymmetry breaking scale m ≡ m(Φ) and the temperature T are such that a m and a T remain constant. These solutions request the presence of special modulifields: i) The universal “noscalemodulus ” Φ, which appears in all N = 1 effective supergravity theories and defines the supersymmetry breaking scale m(Φ). ii) The modulus Φs, which appears in a very large class of string compactifications and has a Φdependent kinetic term. During the time evolution, a 4 ρs remains constant as well, (ρs being the energy density induced by the motion of Φs). The cosmological term Λ(am), the curvature term k(am, aT) and the radiation term cR = a 4 ρ are dynamically generated in a controllable way by radiative and temperature corrections; they are effectively constant during the time evolution. An instantonic Euclidean solution exists and connects via tunneling the inflationary evolution to another cosmological branch. The latter starts with a big bang and, in the case the transition does not occur, ends with a big crunch. Research partially supported by the EU (under the contracts MRTNCT2004005104, MRTN
An Inflationary Model in String Theory
, 2004
"... We construct a model of inflation in string theory after carefully taking into account moduli stabilization. The setting is a warped compactification of Type IIB string theory in the presence of D3 and antiD3branes. The inflaton is the position of a D3brane in the internal space. By suitably adju ..."
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We construct a model of inflation in string theory after carefully taking into account moduli stabilization. The setting is a warped compactification of Type IIB string theory in the presence of D3 and antiD3branes. The inflaton is the position of a D3brane in the internal space. By suitably adjusting fluxes and the location of symmetrically placed antiD3branes, we show that at a point of enhanced symmetry, the inflaton potential V can have a broad maximum, satisfying the condition V ′′ /V ≪ 1 in Planck units. On starting close to the top of this potential the slowroll conditions can be met. Observational constraints impose significant restrictions. As a first pass we show that these can be satisfied and determine the important scales in the compactification to within an order of magnitude. One robust feature is that the scale of inflation is low, H = O(1010) GeV. Removing the observational constraints makes it much easier to construct a slowroll inflationary model. Generalizations and consequences including the possibility of eternal inflation
DFTT 23/05 Cosmic Billiards with Painted Walls in Non Maximal Supergravities.
, 2005
"... The derivation of smooth cosmic billiard solutions by means of the compensator method, introduced by us sometimes ago, is extended to the case of supergravity with non maximal supersymmetry. Here a new key feature is provided by the nonmaximal split nature of the scalar coset manifold. To deal with ..."
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The derivation of smooth cosmic billiard solutions by means of the compensator method, introduced by us sometimes ago, is extended to the case of supergravity with non maximal supersymmetry. Here a new key feature is provided by the nonmaximal split nature of the scalar coset manifold. To deal with this, one has to consider the theory of Tits Satake projections leading to maximal split projected algebras, where the compensator method can be successfully applied and interesting solutions that display several smooth bounces can be derived. The generic bouncing feature of all exact solutions can thus be checked. From the analysis of the Tits Satake projection emerges a regular scheme applicable to all non maximal supergravity models and in particular a challenging so far unobserved structure, that of the paint group Gpaint. This latter, which is preserved through dimensional reduction, provides a powerful tool to codify solutions of the exact supergravity theories in terms of solutions of their Tits Satake projected partners, which are much simpler and manageable. It appears that the dynamical walls on which the cosmic ball bounces come actually in painted copies rotated into each other by the paint group. So the effective