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Supergravity Inspired Warped Compactifications and Effective Cosmological Constants
, 1999
"... We propose a supergravity derivation of the Randall–Sundrum action as an effective description of the dynamics of a brane coupled to the bulk through gravity only. The cosmological constants in the bulk and on the brane, which appear at the classical level when solving the supergravity equations of ..."
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We propose a supergravity derivation of the Randall–Sundrum action as an effective description of the dynamics of a brane coupled to the bulk through gravity only. The cosmological constants in the bulk and on the brane, which appear at the classical level when solving the supergravity equations of motion, are related to physical quantities like the brane electric charge and thus inherit some of their physical properties. The most appealing property is their quantization: in d ⊥ extra dimensions, Λ brane goes like 1/N and Λ bulk like N 2/(d⊥−2). This supergravity origin also explains the apparent finetuning required in the Randall–Sundrum scenario. In our approach, the cosmological constants are derived parameters and cannot be chosen arbitrarily; instead they are determined by the underlying supersymmetric Lagrangian. D3branes of type IIB The coexistence of two hierarchical scales in particle physics is probably the most challenging puzzle to solve before hoping to construct a quantum theory of gravity. When the Schwarzchild radius (R Sch = 2GNm/c 2) of a system of mass m becomes of the same order as its
Gravitational Radius Stabilization in Supersymmetric Warped Compactification
, 2005
"... We examine the possibility of the extra dimensional radius stabilization with only the gravity multiplet in the bulk and some couplings at orbifold fixed points in a supersymmetric RandallSundrum model. Unfortunately, we find that the radius cannot be stabilized in all the cases we consider. Depend ..."
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We examine the possibility of the extra dimensional radius stabilization with only the gravity multiplet in the bulk and some couplings at orbifold fixed points in a supersymmetric RandallSundrum model. Unfortunately, we find that the radius cannot be stabilized in all the cases we consider. Depending on parameters in the model, the fifth dimension collapses or its radius goes to infinity. While the former case is theoretically disastrous, the latter implies that the socalled “RS II” model is automatically realized in our setup. Although the radius is not stabilized, there is nothing wrong with the resultant RS II model, because it is not only phenomenologically viable but also free from the gauge hierarchy problem thanks to its supersymmetric extension.
NSFITP0177 N = 3 Warped Compactifications
"... Orientifolds with threeform flux provide some of the simplest string examples of warped compactification. In this paper we show that some models of this type have the unusual feature of D = 4, N = 3 spacetime supersymmetry. We discuss their construction and low energy physics. Although the local fo ..."
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Orientifolds with threeform flux provide some of the simplest string examples of warped compactification. In this paper we show that some models of this type have the unusual feature of D = 4, N = 3 spacetime supersymmetry. We discuss their construction and low energy physics. Although the local
MITCTP4010 Decaying Hidden Dark Matter in Warped Compactification
, 902
"... The recent ATIC and PAMELA experiments have observed an excess of electrons and positrons, but not antiprotons, in the high energy cosmic rays. To explain this result, we construct a decaying hidden dark matter model in string theory compactification that incorporates the following two ingredients, ..."
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, the hidden dark matter scenario in warped compactification and the phenomenological proposal of hidden light particles that decay to the Standard Model. In this model, on higher dimensional warped branes, various warped KaluzaKlein particles and the zeromode of gauge field play roles of the hidden dark
BraneWorld Cosmology in Higher Derivative Gravity or Warped Compactification
 in the Nexttoleading Order of AdS/CFT Correspondence”, JHEP 07 (2000) 049, [http://arXiv.org/abs/hepth/0006232
"... The general model of higher derivative (HD) gravity is considered. The search of braneworld cosmology in such theory is presented when bulk is d5 AdS and boundary is spherical, hyperbolic or flat (single) brane. It is found the wide range of theory parameters where such cosmology may be realized. S ..."
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Cited by 25 (2 self)
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The general model of higher derivative (HD) gravity is considered. The search of braneworld cosmology in such theory is presented when bulk is d5 AdS and boundary is spherical, hyperbolic or flat (single) brane. It is found the wide range of theory parameters where such cosmology may be realized. Special attention is paid to the version of HD theory representing SG dual of N = 2 Sp(N) SCFT (in nexttoleading order of large N expansion). In particular, it is shown that inflationary brane Universe does not occur for SG dual while hyperbolic brane occurs (which was not possible in leading order). The quantum effects of CFT living on the brane (via the corresponding conformal anomaly induced effective action) may qualitatively change the results of classical analysis. There appears inflationary (or hyperbolic) brane Universe induced by only quantum effects. In AdS/CFT correspondence (nexttoleading order) the addition of such CFT effective action (in some energy region) is naturally explained in terms of holographic renormalization group. It results in the possibility of quantum creation of inflationary brane Universe (with small rate) even for SG dual.
Hierarchies from Fluxes in String Compactifications
, 2002
"... Warped compactifications with significant warping provide one of the few known mechanisms for naturally generating large hierarchies of physical scales. We demonstrate that this mechanism is realizable in string theory, and give examples involving orientifold compactifications of IIB string theory a ..."
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Cited by 713 (33 self)
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Warped compactifications with significant warping provide one of the few known mechanisms for naturally generating large hierarchies of physical scales. We demonstrate that this mechanism is realizable in string theory, and give examples involving orientifold compactifications of IIB string theory
Lectures on warped compactifications and stringy brane constructions,” arXiv:hepth/0009247
 Rev. D
, 2002
"... In these lectures, two different aspects of brane world scenarios in 5d gravity or string theory are discussed. In the first two lectures, work on how warped compactifications of 5d gravity theories can change the guise of the gauge hierarchy problem and the cosmological constant problem is reviewed ..."
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Cited by 8 (0 self)
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In these lectures, two different aspects of brane world scenarios in 5d gravity or string theory are discussed. In the first two lectures, work on how warped compactifications of 5d gravity theories can change the guise of the gauge hierarchy problem and the cosmological constant problem
hepth/0112079 de Sitter Spacetimes from Warped Compactifications of IIB String Theory
, 2002
"... We continue our study of codimension two solutions of warped spacetime varying compactifications of string theory. In this letter we discuss a nonsupersymmetric solution of the classical type IIB string theory with de Sitter gravity on a codimension two uncompactified part of spacetime. A nonzero ..."
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Cited by 13 (0 self)
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We continue our study of codimension two solutions of warped spacetime varying compactifications of string theory. In this letter we discuss a nonsupersymmetric solution of the classical type IIB string theory with de Sitter gravity on a codimension two uncompactified part of spacetime. A non
hepth/0201187 Relating the Cosmological Constant and Supersymmetry Breaking in Warped Compactifications of IIB String Theory
, 2002
"... It has been suggested that the observed value of the cosmological constant is related to the supersymmetry breaking scale Msusy through the formula Λ ∼ M 4 p(Msusy/Mp) 8. We point out that this relation naturally arises in the codimension two solutions of warped spacetime varying compactifications o ..."
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It has been suggested that the observed value of the cosmological constant is related to the supersymmetry breaking scale Msusy through the formula Λ ∼ M 4 p(Msusy/Mp) 8. We point out that this relation naturally arises in the codimension two solutions of warped spacetime varying compactifications
Results 21  30
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3,674