Related papers: Hierarchies without Symmetries from Extra Dimensio…
We provide a thorough exposition of recent results on the quantum stabilization of cosmic strings. Stabilization occurs through the coupling to a heavy fermion doublet in a reduced version of the standard model. The study combines the…
We propose an extra-dimensional mechanism that adequately suppresses the rate of proton decay mediated by the X-bosons in grand unified theories. The X-bosons and their Kaluza-Klein modes are localized in the extra spatial dimensions due to…
A non anomalous horizontal $U(1)_H$ gauge symmetry can be responsible for the fermion mass hierarchies of the minimal supersymmetric standard model. Imposing the consistency conditions for the absence of gauge anomalies yields the following…
Pseudo-Hermitian (including $\mathcal{PT}$-symmetric) field theories support phenomenology that cannot be replicated in standard Hermitian theories. We describe a concrete example in which the vortex solutions that are realised in a…
We consider variation of coupling strengths and mass ratios in and beyond the Standard Model, in the light of various mechanisms of mass generation. In four-dimensional unified models, variations in charged particle thresholds, light quark…
We explore the possibility of modeling electroweak physics in a warped extra dimension with a soft wall. The infrared boundary is replaced with a smoothly varying dilaton field that provides a dynamical spacetime cutoff. We analyze gravity,…
It has been recently argued that realistic models with warped extra dimensions can have Kaluza-Klein particles accessible at the Large Hadron Collider if a custodial symmetry, SU(2)_V \times P_{LR}, is used to protect the T parameter and…
We give a pedagogical introduction to the physics of large extra dimensions. We focus our discussion on minimal extensions of the Standard Model in which gauge fields may propagate in a single, compact extra dimension while the fermions are…
Warped extra dimensions allow a novel way of solving the hierarchy problem, with all fundamental mass parameters of the theory naturally of the order of the Planck scale. The observable value of the Higgs vacuum expectation value is…
We describe higher-dimensional theories whose low-energy 4D descriptions contain larger gauge or global symmetry groups. As an example, we construct a Higgsless SU(2) x U(1) model of electroweak symmetry breaking. The 5D SU(2) gauge…
We point out a dramatic new experimental signature for a class of theories with extra dimensions, where quarks and leptons are localized at slightly separated parallel ``walls'' whereas gauge and Higgs fields live in the bulk of the extra…
The version of the warp model that we proposed to explain the mass scale hierarchy has been extended by the introduction of one or more singularities in the metric. We restricted ourselves to a real massless scalar field supposed to…
If nature is described by string theory, and if the compactification radius is large (as suggested by the unification of couplings), then the theory is in a regime best described by the low energy limit of $M$-theory. We discuss some…
We propose a new higher-dimensional mechanism for solving the Hierarchy Problem. The Weak scale is generated from a large scale of order the Planck scale through an exponential hierarchy. However, this exponential arises not from gauge…
All the boundary conditions compatible with the reduction of a five dimensional spinor field of bulk mass $M$ in a compactified warped space to a four dimensional brane are derived from the hermiticity conditions of the relevant operator.…
Consequences of a non-trivial scalar field background for an effective 4D theory were studied in the context of one compact extra dimension. The periodic background that appears within the (1+4)-dimensional $\phi^4$ theory was found and the…
We develop a 5d model for ElectroWeak physics based on a non compact warped extra dimension of finite length, known as the soft wall scenario, where all the dynamical degrees of freedom propagate in the 5d bulk. We solve the equations of…
Previous studies have shown how the three generations of the Standard Model fermions can arise from a single generation in more than four dimensions, and how off-diagonal neutral couplings arise for gauge-boson Kaluza-Klein recurrences.…
In supersymmetric models with scalar sequestering, superconformal strong dynamics in the hidden sector suppresses the low-energy couplings of mass dimension two, compared to the squares of the dimension one parameters. Taking into account…
The extended technicolor theory is a candidate of the physics beyond the standard model. To explain the mass hierarchy of the quarks and leptons, the extended technicolor gauge symmetry must hierarchically break to the technicolor gauge…