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609
RS1, custodial isospin and precision tests
 JHEP 0308
"... We study precision electroweak constraints within a RS1 model with gauge fields and fermions in the bulk. The electroweak gauge symmetry is enhanced to SU(2)L ×SU(2)R × U(1)B−L, thereby providing a custodial isospin symmetry sufficient to suppress excessive contributions to the T parameter. We then ..."
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Cited by 60 (1 self)
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We study precision electroweak constraints within a RS1 model with gauge fields and fermions in the bulk. The electroweak gauge symmetry is enhanced to SU(2)L ×SU(2)R × U(1)B−L, thereby providing a custodial isospin symmetry sufficient to suppress excessive contributions to the T parameter. We then construct complete models, complying with all electroweak constraints, for solving the hierarchy problem, without supersymmetry or large hierarchies in the fundamental couplings. Using the AdS/CFT correspondence our models can be interpreted as dual to a strongly coupled conformal Higgs sector with global custodial symmetry, gauge and fermionic matter being fundamental fields external to the CFT. This scenario has interesting collider signals, distinct from other RS models in the literature.
Field Dependent Gauge Couplings in Locally Supersymmetric Effective Quantum Field Theories,” Nucl. Phys. B422
, 1994
"... We investigate the field dependence of the gauge couplings of locally supersymmetric effective quantum field theories. We find that the Weyl rescaling of supergravity gives rise to WessZumino terms that affect the gauge couplings at the oneloop level. These WessZumino terms are crucial in assurin ..."
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Cited by 51 (0 self)
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We investigate the field dependence of the gauge couplings of locally supersymmetric effective quantum field theories. We find that the Weyl rescaling of supergravity gives rise to WessZumino terms that affect the gauge couplings at the oneloop level. These WessZumino terms are crucial in assuring supersymmetric consistency of both perturbative and nonperturbative gauge interactions. At the perturbative level, we distinguish between the holomorphic Wilsonian gauge couplings and the physicallymeasurable momentumdependent effective gauge couplings; the latter are affected by the Konishi and the superWeyl anomalies and their fielddependence is nonholomorphic. At the nonperturbative level, we show how consistency of the scalar potential generated by infraredstrong gauge interactions with the local supersymmetry requires a very specific form of the effective superpotential. We use this superpotential to determine the dependence of the supersymmetric condensates of a strongly interacting gauge theory on its (fielddependent) Wilsonian gauge coupling and the Yukawa couplings of the matter fields. The article concludes with the discussion of the fielddependent nonperturbative phenomena in the context of string unification. 2
The minimal composite Higgs model
 Nucl. Phys. B
"... Composite Higgs models [1] represent an attractive variation of the Technicolor paradigm [2]. In these theories the Standard Model (SM) Higgs doublet is the bound state of a strongly interacting sector with flavor symmetry G. It forms at a scale fπ, the analog of the QCD pion decay constant, as the ..."
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Cited by 43 (0 self)
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Composite Higgs models [1] represent an attractive variation of the Technicolor paradigm [2]. In these theories the Standard Model (SM) Higgs doublet is the bound state of a strongly interacting sector with flavor symmetry G. It forms at a scale fπ, the analog of the QCD pion decay constant, as the Goldstone boson associated with the dynamical breaking of the global symmetry G. The couplings of the SM matter and gauge fields to the strong sector break G explicitly, and induce a oneloop Higgs potential that triggers the electroweak symmetry breaking (EWSB) at the scale v ≤ fπ. In the limit of a large separation ǫ = v/fπ ≪ 1, all the massive bound states of the strong sector decouple, and one is left with the lowenergy spectrum of the Standard Model. This means that all corrections to the electroweak precision observables constrained by LEP and SLD experiments will be suppressed by powers of ǫ. In this talk I will discuss an interesting realization of this old idea which has been recently found in the framework of extradimensional warped models
Theory of preasymptotic effects in weak inclusive decays; hepph/9405246
"... I give an introduction to the theory of preasymptotic effects based on the systematic OPE/HQET expansion in 1/mQ where mQ is the heavy quark mass. The general idea is explained in two most instructive examples, with an emphasis on pedagogical aspects. Some important results of the last year are revi ..."
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Cited by 32 (13 self)
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I give an introduction to the theory of preasymptotic effects based on the systematic OPE/HQET expansion in 1/mQ where mQ is the heavy quark mass. The general idea is explained in two most instructive examples, with an emphasis on pedagogical aspects. Some important results of the last year are reviewed. In discussing the issue of the quarkhadron duality, one of the basic ingredients of the theory, I prove that the operator product expansion per se is an asymptotic expansion. The behavior of the high order terms in this expansion determines the onset of duality and the accuracy of the duality relations. The factorial divergence of the highorder terms in OPE implies a sophisticated analytical structure in the αs plane, with terms of the type exp[ − exp(1/αs)]. Although the weak inclusive decays of heavy flavor hadrons are driven by weak interactions the theory of preasymptotic effects is an important applied branch of QCD. The theory has been gradually crystallizing from the eighties, with a decisive breakthrough achieved recently, in the last two or three years. I will try to summarize what we know and what
Baryon number in warped GUTs: Model building and (dark matter related) phenomenology,” JCAP 0502
, 2005
"... Abstract: In the past year, a new framework for electroweak symmetry breaking (with or without Higgs) involving SU(2)L × SU(2)R × U(1)B−L in higher dimensional warped geometry has been suggested. In this work, we embed this gauge structure into a GUT such as SO(10) or Pati–Salam. We showed recently ..."
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Cited by 27 (0 self)
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Abstract: In the past year, a new framework for electroweak symmetry breaking (with or without Higgs) involving SU(2)L × SU(2)R × U(1)B−L in higher dimensional warped geometry has been suggested. In this work, we embed this gauge structure into a GUT such as SO(10) or Pati–Salam. We showed recently (in hepph/0403143) that in a warped GUT, a stable Kaluza–Klein fermion can arise as a consequence of imposing proton stability. Here, we specify a complete realistic model where this particle is a weakly interacting right–handed neutrino, and present a detailed study of this new dark matter candidate, providing relic density and detection predictions. We discuss phenomenological aspects associated with the existence of other light ( � TeV) KK fermions, whose lightness is a direct consequence of the top quark’s heaviness. The AdS/CFT interpretation of this construction is also reviewed. Most of our qualitative results do not depend on the nature of the breaking of the electroweak sector provided that it happens near the TeV brane.
Flow equation of quantum Einstein gravity in a higherderivative truncation, Phys
 Rev. D
, 2002
"... Motivated by recent evidence indicating that Quantum Einstein Gravity (QEG) might be nonperturbatively renormalizable, the exact renormalization group equation of QEG is evaluated in a truncation of theory space which generalizes the EinsteinHilbert truncation by the inclusion of a higherderivativ ..."
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Cited by 21 (2 self)
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Motivated by recent evidence indicating that Quantum Einstein Gravity (QEG) might be nonperturbatively renormalizable, the exact renormalization group equation of QEG is evaluated in a truncation of theory space which generalizes the EinsteinHilbert truncation by the inclusion of a higherderivative term (R 2). The betafunctions describing the renormalization group flow of the cosmological constant, Newton’s constant, and the R 2coupling are computed explicitly. The fixed point properties of the 3dimensional flow are investigated, and they are confronted with those of the 2dimensional EinsteinHilbert flow. The nonGaussian fixed point predicted by the latter is found to generalize to a fixed point on the enlarged theory space. In order to test the reliability of the R 2truncation near this fixed point we analyze the residual scheme dependence of various universal quantities; it turns out to be very weak. The two truncations are compared in detail, and their numerical predictions are found to agree with a suprisingly high precision. Due to the consistency of the results it appears increasingly unlikely that the nonGaussian fixed
Geometric entropy, area, and strong subadditivity
, 2004
"... The trace over the degrees of freedom located in a subset of the space transforms the vacuum state into a mixed density matrix with non zero entropy. This geometric entropy is believed to be deeply related to the entropy of black holes. Indeed, previous calculations in the context of quantum field t ..."
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Cited by 17 (2 self)
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The trace over the degrees of freedom located in a subset of the space transforms the vacuum state into a mixed density matrix with non zero entropy. This geometric entropy is believed to be deeply related to the entropy of black holes. Indeed, previous calculations in the context of quantum field theory, where the result is actually ultraviolet divergent, have shown that the geometric entropy is proportional to the area for a very special type of subsets. In this work we show that the area law follows in general from simple considerations based on quantum mechanics and relativity. An essential ingredient in our approach is the strong subadditive property of the quantum mechanical entropy. I.
Environmental Dependence of Masses and Coupling Constants
, 709
"... We construct a class of scalar field models coupled to matter that lead to the dependence of masses and coupling constants on the ambient matter density. Such models predict a deviation of couplings measured on the Earth from values determined in lowdensity astrophysical environments, but do not ne ..."
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Cited by 15 (0 self)
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We construct a class of scalar field models coupled to matter that lead to the dependence of masses and coupling constants on the ambient matter density. Such models predict a deviation of couplings measured on the Earth from values determined in lowdensity astrophysical environments, but do not necessarily require the evolution of coupling constants with the redshift in the recent cosmological past. Additional laboratory and astrophysical Perhaps the most astonishing fundamental observation of the last decade was the discovery of dark energy. So far, all cosmological data are consistent with the simplest possibility: dark energy is just a new fundamental constant of nature, which does not evolve over cosmological redshifts. On the other hand, it is intriguing to think about alternative explanations
Resonance scattering phase shift on a nonrest frame lattice, Nucl. Phys. B450
, 1995
"... Many low energy hadrons, such as the rho, can observed as resonances in scattering experiments. A proposal by Lüscher enables one to determine infinite volume elastic scattering phases from the twoparticle energy spectrum measured from finite periodic lattices. In this work, we generalize the forma ..."
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Cited by 15 (0 self)
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Many low energy hadrons, such as the rho, can observed as resonances in scattering experiments. A proposal by Lüscher enables one to determine infinite volume elastic scattering phases from the twoparticle energy spectrum measured from finite periodic lattices. In this work, we generalize the formalism to the case where the total momentum of the particles is nonzero; i.e.,the lattice frame is not the centerofmass frame of the scattering particles. There are several advantages to this procedure including making a wider variety of center of mass energies accessible with a fixed lattice volume, and making the avoided level crossing in a Pwave decay occur with a smaller volume. The formalism is tested with a simple lattice model of two fields with different masses and a 3point coupling in 3 + 1 dimensions. We find remarkable agreement between the restframe and nonrestframe scattering. IUHET 297 1
Modular invariant partition functions in the quantum Hall effect
"... We study the partition function for the lowenergy edge excitations of the incompressible electron fluid. On an annular geometry, these excitations have opposite chiralities on the two edges; thus, the partition function takes the standard form of rational conformal field theories. In particular, it ..."
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Cited by 14 (3 self)
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We study the partition function for the lowenergy edge excitations of the incompressible electron fluid. On an annular geometry, these excitations have opposite chiralities on the two edges; thus, the partition function takes the standard form of rational conformal field theories. In particular, it is invariant under modular transformations of the toroidal geometry made by the angular variable and the compact Euclidean time. The Jain series of plateaus have been described by two types of edge theories: the minimal models of the W1+∞ algebra of quantum areapreserving diffeomorphisms, and their nonminimal version, the theories with ̂ U(1) × ̂ SU(m) 1 affine algebra. We find modular invariant partition functions for the latter models. Moreover, we relate the Wen topological order to the modular transformations and the Verlinde fusion algebra. We find new, nondiagonal modular invariants which describe edge theories with extended symmetry algebra; their Hall conductivities match the experimental values beyond the Jain series.