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1.
Starting from the previously constructed effective supergravity theory below the scale of U(1) breaking in orbifold compactifications of the weakly coupled heterotic string, we study the effective theory below the scale of supersymmetry breaking by gaugino and matter condensation in a hidden sector. Questions we address include vacuum stability and the masses of the various moduli fields, including those associated with flat directions at the U(1) breaking scale, and of their fermionic superpartners. The issue of soft supersymmetry-breaking masses in the observable sector presents a particularly serious challenge for this class of models.  相似文献   

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In this article we study the most general compactifications of eleven-dimensional supergravity to four-dimensional anti-de Sitter space, using a seven-dimensional internal compact manifold whose local isometry group contains the exceptional group, G2. We find that the only such compactifications are the well known ones involving the round seven-sphere. We discuss the implications of this result for conjectured relationship between the eleven-dimensional theory and gauged N = 8 supergravity.  相似文献   

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The scale invariant gravity theory coupled to conformally invariant matter is investigated. We show that in the non‐supersymmetric case the conformally coupled scalars belong to an manifold, while in the supersymmetric case the scalar manifold becomes isomorphic to the Kählerian space =. In both cases when the underlying scale symmetry is preserved the vacuum corresponds to de Sitter space. Once the scale symmetry is broken by quantum effects, a transition to flat space becomes possible. We argue that the scale violating terms are induced by anomalies related to a symmetry. The anomaly is resolved via the gauging of a Peccei‐Quinn axion shift symmetry. The theory describes an inflationary transition from de Sitter to flat Minkowski space, very similar to the Starobinsky inflationary model. The extension to metastable de Sitter superstring vacua is also investigated. The scalar manifold is extended to a much richer manifold, but it contains always as a sub‐manifold. In superstrings the metastability is induced by axions that cure the anomalies in chiral (or even ) supersymmetric vacua via a Green‐Schwarz/Peccei‐Quinn mechanism generalized to four dimensions. We present some typical superstring models and discuss the possible stabilization of the no‐scale modulus.  相似文献   

5.
Decomposition theorems for certain representations of Kac-Moody algebras which are needed for the construction of modular invariant unitary conformal models are proved. It is shown that allc<1 modular invariant models can then be recovered from gauged free fermionic models, including the exceptional cases.This work was supported in part by the Director, Office of Energy Research, Office of High Energy and Nuclear Physics, Division of High Energy Physics of the U.S. Department of Energy under Contract DE-AC03-76SF00098 and in part by the National Science Foundation under grant PHY85-15857Supported by the Swiss National Science FoundationSupported in part by the American-Israeli Binational Science Foundation and the Israeli Academy of Sciences  相似文献   

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A complete classification of thephysical modular invariant partition functions for the WZNW models is known for very few affine algebras and levels, the most significant being all levels ofSU(2), and level 1 of all simple algebras. In this paper we solve the classification problem forSU(3) modular invariant partition functions, all levels. Our approach will also be applicable to other affine Lie algebras, and we include some preliminary work in that direction, including a sketch of a new proof forSU(2).  相似文献   

8.
We give two results concerning the construction of modular invariant partition functions for conformal field theories constructed by tensoring together other conformal field theories. First we show how the possible modular invariants for the tensor product theory are constrained if the allowed modular invariants of the individual conformal field theory factors have been classified. We illustrate the use of these constraints for theories of the type SU(2)KASU(2)KB, finding all consistent theories for KA, KB odd. Second we show how known diagonal modular invariants can be used to construct some inherently asymmetric ones where the holomorphic and antiholomorphic theories do not share the same chiral algebra. Some explicit examples are given.  相似文献   

9.
There has been much interest recently in the problem of anomalies in field theory. This is a consequence of recent work on the regularization of stress tensors, and of renewed interest in the axial vector anomaly. In this paper, I shall present a derivation of both the trace anomaly and the axial vector anomaly for the spin-32 Majorana field using a zeta function regularization procedure. This result is also of interest in supergravity and extended supergravity.  相似文献   

10.
We construct on S7 an SU(4) invariant solution of d = 11 supergravity in which the metric on the seven-sphere, regarded as a U(1) bundle overCP3, is distorted by stretching the U(1) fibers, and the four-index field strength FMNPQ is non-zero in the S7 directions. This solution presumably corresponds to the SU(4) invariant extremum of the de Wit-Nicolai potential.  相似文献   

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The elimination of unphysical degrees of freedom from a quantized massless Rarita-Schwinger field interacting with a (quantized or classical) gravitational field is analyzed on the one-loop level. It is shown that, beside the ordinary Faddeev-Popov ghosts, an extra ghost is needed to remove the effects of unphysical modes. The new ghost only couples to the S-matrix if the gauge-fixing of the Rarita-Schwinger field involves the gravitational field, but it is necessary in the partition function for other gauge choices.  相似文献   

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Supersymmetric cascades, involving charginos and neutralinos at various stages, contribute in a significant way to Higgs production at the LHC. We explore the nature of such cascades, completely relaxing the universality of the gaugino masses. It is found that the deviation from the scenario with universal gaugino masses would be reflected in the relative production rates for the lightest neutral Higgs and the charged Higgses.  相似文献   

16.
We study phenomenological features in an extended gauge mediation SUSY breaking model that has non-universal gaugino masses and CP phases. We show that large CP phases in soft SUSY breaking parameters can be consistent with the constraints coming from the electric dipole moment (EDM) of an electron, a neutron, and also a mercury atom. Masses of the superpartners are not necessarily required to be larger than 1 TeV but allowed to be O(100) GeV. We also investigate the mass spectrum of Higgs scalars and their couplings to gauge bosons in that case. Compatibility of this model with the present experimental data on the Higgs sector is discussed.  相似文献   

17.
The compatibility of Euclidean supergravity with curvature satisfying (a) self-duality and (b) a double duality Ansatz are investigated. The Minkowskian version of (b) is also considered.  相似文献   

18.
The supergravity group is found to be the direct product of general covariance groups in complex conjugated left and right handed superspaces. The ordinary space-time coordinate and the axial gravitational superfield are the real and imaginary part of the complex coordinate, respectively.  相似文献   

19.
We consider the BRS identities for N = 1 supergravity in a covariant gauge. It is shown that, as in the axial gauge, the anti-symmetric part of the vierbein does contribute to the BRS identities, even though one can choose a gauge in which it does not propagate.  相似文献   

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