Resonance at 125 GeV: Higgs or Dilaton/Radion?

We consider the possibility that the new particle that has been observed at 125 GeV is not the Standard Model (SM) Higgs, but instead the dilaton associated with an approximate conformal symmetry that has been spontaneously broken. We focus on dilatons that arise from theories of technicolor, or from theories of the Higgs as a pseudo-Nambu-Goldstone boson (pNGB), that involve strong conformal dynamics in the ultraviolet. In the pNGB case, we are considering a framework where the Higgs particle is significantly heavier than the dilaton and has therefore not yet been observed. In each of the technicolor and pNGB scenarios, we study both the case when the SM fermions and gauge bosons are elementary, and the case when they are composites of the strongly interacting sector. Our analysis incorporates conformal symmetry violating effects, which are necessarily present since the dilaton is not massless, and is directly applicable to a broad class of models that stabilize the weak scale and involve strong conformal dynamics. Since the AdS/CFT correspondence relates the radion in Randall-Sundrum (RS) models to the dilaton, our results also apply to RS models with the SM fields localized on the infrared brane, or in the bulk. We identify the parameters that can be used to distinguish the dilatons associated with the several different classes of theories being considered from each other, and from the SM Higgs. We perform a fit to all the available data from several experiments and highlight the key observations to extract these parameters. We find that at present, both the technicolor and pNGB dilaton scenarios provide a good fit to the data, comparable to the SM Higgs. We indicate the future observations that will help to corroborate or falsify each scenario.Comment: 41 pages, 4 figures. Analysis updated using current theoretical limits on dimensions of CFT operators. References added. Version to appear on JHE

Interactions of a Stabilized Radion and Duality

We determine the couplings of the graviscalar radion in Randall-Sundrum models to Standard Model fields propagating in the bulk of the space, taking into account effects arising from the dynamics of the Goldberger-Wise scalar that stabilizes the size of the extra dimension. The leading corrections to the radion couplings are shown to arise from direct contact interactions between the Goldberger-Wise scalar and the Standard Model fields. We obtain a detailed interpretation of the results in terms of the holographic dual of the radion, the dilaton. In doing so, we determine how the familiar identification of the parameters on the two sides of the AdS/CFT correspondence is modified in the presence of couplings of the bulk Standard Model fields to the Goldberger-Wise scalar. We find that corrections to the form of the dilaton couplings from effects associated with the stabilization of the extra dimension are suppressed by the square of the ratio of the dilaton mass to the Kaluza-Klein scale, in good agreement with results from the CFT side of the correspondence.Comment: 22 pages plus appendices and reference

Meta-Stable Brane Configuration and Gauged Flavor Symmetry

Starting from an N=1 supersymmetric electric gauge theory with the gauge group Sp(N_c) x SO(2N_c') with fundamentals for the first gauge group factor and a bifundamental, we apply Seiberg dual to the symplectic gauge group only and arrive at the N=1 supersymmetric dual magnetic gauge theory with dual matters including the gauge singlets and superpotential. By analyzing the F-term equations of the dual magnetic superpotential, we describe the intersecting brane configuration of type IIA string theory corresponding to the meta-stable nonsupersymmetric vacua of this gauge theory.Comment: 16 pp, 3 figures; stability analysis in page 7 and 8 added and the presentation improved; reduced bytes of figures and to appear in MPL

The GUT Scale and Superpartner Masses from Anomaly Mediated Supersymmetry Breaking

We consider models of anomaly-mediated supersymmetry breaking (AMSB) in which the grand unification (GUT) scale is determined by the vacuum expectation value of a chiral superfield. If the anomaly-mediated contributions to the potential are balanced by gravitational-strength interactions, we find a model-independent prediction for the GUT scale of order $M_{\rm Planck} / (16\pi^2)$. The GUT threshold also affects superpartner masses, and can easily give rise to realistic predictions if the GUT gauge group is asymptotically free. We give an explicit example of a model with these features, in which the doublet-triplet splitting problem is solved. The resulting superpartner spectrum is very different from that of previously considered AMSB models, with gaugino masses typically unifying at the GUT scale.Comment: 17 page

Power Generalized KM-Transformation for Non-Monotone Failure Rate Distribution

Lifetime models with a non-monotone hazard rate $\hspace{0.12cm}$ function have a wide range of applications in engineering and lifetime data analysis. There are different bathtub shaped failure rate models that are available in reliability literature. Kavya and Manoharan (2021) introduced a new transformation called KM-transformation which was found to be more useful in reliability and lifetime data analysis. Power generalization technique would be the best approach to deal with a system whose components are connected in series, in which the distribution of the component is KM-transformation of any lifetime model. In this article, we introduce a new lifetime model, Power Generalized KM-Transformation (PGKM) for Non-Monotone Failure Rate Distribution, which shows monotone and non-monotone behavior for the hazard rate function for different choices of values of parameters. We derive the moments, moment generating function, characteristic function, quantiles, entropy etc of the proposed distribution. Distributions of minimum and maximum are obtained. Estimation of parameters of the distribution is performed via maximum likelihood method. A simulation study is performed to validate the maximum likelihood estimator (MLE). Analysis of three sets of real data are given

Prospects for Mirage Mediation

Mirage mediation reduces the fine-tuning in the minimal supersymmetric standard model by dynamically arranging a cancellation between anomaly-mediated and modulus-mediated supersymmetry breaking. We explore the conditions under which a mirage "messenger scale" is generated near the weak scale and the little hierarchy problem is solved. We do this by explicitly including the dynamics of the SUSY-breaking sector needed to cancel the cosmological constant. The most plausible scenario for generating a low mirage scale does not readily admit an extra-dimensional interpretation. We also review the possibilities for solving the mu/Bmu problem in such theories, a potential hidden source of fine-tuning.Comment: 14 page