Related papers: Limits on extra dimensions in orbifold compactific…
The effects of extra dimensions on gauge coupling unification is studied. We start with a comparison between power law running of the gauge couplings in models with extra dimensions and logarithmic running that happens in many realistic…
In this talk I summarize several recent results concerning the four-dimensional effective supergravity obtained using a Calabi-Yau compactification of the $E_8\times E_8$ heterotic string from M-theory. A simple macroscopic study is…
Models with universal extra dimensions predict that each Standard Model particle is accompanied by a tower of Kaluza-Klein resonances. Canonical searches for the production and cascade decays of first Kaluza-Klein modes through missing…
In this paper we discuss the issues of supersymmetry breaking and moduli stabilization within the context of E_8 x E_8 heterotic orbifold constructions and, in particular, we focus on the class of "mini-landscape" models. In the…
In recent years it has been realized that in string/$M$ theories compactified to four dimensions which satisfy cosmological constraints, it is possible to make some generic predictions for particle physics and dark matter: a non-thermal…
Over the past three decades, considerable effort has been devoted to studying the rich and diverse phenomenologies of heterotic strings exhibiting spacetime supersymmetry. Unfortunately, during this same period, there has been relatively…
Production of exotic states at LHC is considered in the large radius compactification scenario. We envisage a five dimensional theory for a scalar field in five dimensional flat spacetime. It is compactified on a circle, $S^1$, with radius,…
We study the unitarity bounds of the scattering amplitudes in the extra dimensional gauge theory where the gauge symmetry is broken by the boundary condition. The estimation of the amplitude of the diagram including four massive gauge…
A five dimensional N=1 supersymmetric theory compactified on the orbifold $S^1/\mathbb{Z}_2$ is constructed. Gauge fields and $SU(2)_L$ singlets propagate in the bulk ($U$-states) while $SU(2)_L$ doublets are localized at an orbifold fixed…
In minimal theories with extra spatial dimensions at scales mu_0 much lower than the conventional GUT scale, unification can give too-large predictions for alpha_3(M_Z) given alpha_1(M_Z) and alpha_2(M_Z) as empirical input. We…
We study the implications of extra dimensions of size $R\sim 1/TeV$ on electroweak and flavor physics due to the presence of Kaluza-Klein excitations of the SM gauge-bosons. We consider several scenarios with the SM fermions either living…
We recently constructed type-IIB compactifications to four dimensions depending on a single additional coordinate, where a five-form flux $\Phi$ on an internal torus leads to a constant string coupling. Supersymmetry is fully broken when…
Possible experimental manifestations of the contribution of heavy Kaluza-Klein particles, within a simple scalar model in six dimensions with spherical compactification, are studied. The approach is based on the assumption that the inverse…
We study the radiative spontaneous electroweak symmetry breaking in the extra dimensions scenarios of the standard model extension proposed by Antoniadis {\it et al}, Dienes {\it et al.} and Pomarol {\it et al.}. In the framework of…
We discuss the collider signals of large extra dimensions in which gravity as well as the SM particles propagate into the extra dimensions. These signals arise either from the production of Kaluza-Klein excitations of the SM particles and…
We argue that supersymmetry breaking by gaugino condensation in the strongly coupled heterotic string can be described by an analogue of Scherk-Schwarz compactification on the eleventh dimension in M-theory. The M-theory scale is identified…
In this paper I will further investigate the spectrum of quantum gravity or string theories at large number of dimensions. We will see that volumes of certain orbifolds shrink at large D. It follows that the mass spectra of the leading…
We consider the Kaluza-Klein scenario in which gravity propagates in the $4+n$ dimensional bulk of spacetime and the Standard Model particles are confined to a 3-brane. We calculate the gauge boson self-energy corrections arising from the…
We derive type IIB vacua which are very promising to put string theory to experimental test. These are Calabi-Yau compactifications with a 4D fibration over a 2D base. The moduli are fixed in such a way to obtain a very anisotropic…
We study total and partial supersymmetry breaking by freely acting orbifolds, or equivalently by Scherk-Schwarz compactifications, in type I string theory. In particular, we describe a four-dimensional chiral compactification with…