D-dimensional Randall-Sundrum models from Brans-Dicke theory and Kaluza-Klein modes

We investigate the spectroscopy of scalar and vector Kaluza-Klein modes that arise in a deformed Randall-Sundrum model that is constructed from Brans-Dicke theory. The non-minimal coupling in the Brans Dicke theory translates into a deformation of the Randall-Sundrum geometry that depends on the Brans-Dicke parameter $\omega$. We find that the $\omega$ parameter has a non-trivial effect in the spectroscopy of scalar and vector Kaluza-Klein modes. Our results suggest the interpretation of $\omega$ as a fine-tuning parameter.Comment: 16 pages, 5 figures. Fig. 5 was corrected. We added new physical discussion

Higher order dilaton gravity: brane equations of motion in the covariant formulation

Dilaton gravity with general brane localized interactions is investigated. Models with corrections up to arbitrary order in field derivatives are considered. Effective gravitational equations of motion at the brane are derived in the covariant approach. Dependence of such brane equations on the bulk quantities is discussed. It is shown that the number of the bulk independent brane equations of motion depends strongly on the symmetries assumed for the model and for the background. Examples with two and four derivatives of the fields are presented in more detail.Comment: 32 pages, references added, discussion extended, typos corrected, version to be publishe

Holographic methods and gauge-Higgs unification in flat extra dimensions

I review the holographic techniques used to efficiently study models with Gauge-Higgs Unification (GHU) in one extra dimension. The general features of GHU models in flat extra dimensions are then reviewed, emphasizing the aspects related to electroweak symmetry breaking. Two potentially realistic models, based on SU(3) and SO(5) electroweak gauge groups, respectively, are constructed.Comment: Invited contribution to the New Journal of Physics Focus Issue on 'Extra Space Dimensions', 43 pages; v2: minor corrections and improvements; v3: matches journal versio