Related papers: The radiatively corrected Kaluza-Klein masses in a…
The five-dimensional loop quantum Kaluza-Klein cosmology is constructed based on the symmetric reduction of the connection formulation of the full theory. Through semiclassical analysis, the effective scalar constraint for the cosmological…
We review briefly the main features of the Large Extra Dimensions scenario in the framework of weakly coupled Type I string theory. Kaluza-Klein (KK) excitations of the graviton are expected, whereas no KK modes for the gauge bosons arise…
The first higher derivative term of the photon sector of Lorentz-violating QED, with operator of mass dimension $d=5$, is radiatively induced from the fermion sector, in which contains a derivative term with the dimensionless coefficient…
Photon mass and Cartan contortion bounds recently obtained from tiny Lorentz violation observations in cosmology are used to find a limit of ${\lambda}\le 10^{-4}{\alpha}$ for the massive photon-torsion dimensionless coupling. Here…
A new physical origin for electroweak symmetry breaking is proposed, involving compact spatial dimensions of scale 1/R \approx 1 TeV. The higher dimensional theory is supersymmetric, and hence requires the top-quark Yukawa coupling to be…
Recently it has been pointed out that the characteristic quantum-gravity scale could be as low as the weak scale in theories with gravity propagating in higher dimensions. The observed smallness of Newton's constant is a consequence of the…
Electroweak Sudakov logarithms at high energy, of the form alpha/sin^2 theta_W^n log^m s/M_{Z,W}^2, are summed using effective theory (EFT) methods. The exponentiation of Sudakov logarithms and factorization is discussed in the EFT…
We study constraints on models with a flat "Universal'' Extra Dimension in which all Standard Model fields propagate in the bulk. A significantly improved constraint on the compactification scale is obtained from the extended set of…
We consider Kaluza-Klein models with background matter in the form of a multicomponent perfect fluid. This matter provides spherical compactification of the internal space with an arbitrary number of dimensions. The gravitating source has…
This document reviews the general approach to correcting the process e+e-->X->ffbar for radiative effects, where X represents an exchanged gauge boson arising from some new physics. The validity of current methods is discussed in the…
We explore the weak-field phenomenology of a compact star spacetime modified by quantum gravitational corrections derived from the effective field theoretical (EFT) approach by Calmet et al. [1]. These corrections, encoded in non-local…
The influence of dispersion on the differential scattering cross section in the vicinity of the first diffraction minimum is revisited for collision energies between 200 and 450 MeV. Transient nuclear excitations in the giant resonance…
In this brief review we discuss the viability of a multidimensional geometrical theory with one compactified dimension. We discuss the case of a Kaluza Klein fifth dimensional theory, addressing the problem by an overview of the…
We entertain the idea that a suitable background of cold (very low momentum) pseudoscalar particles or condensate, may trigger a background that effectively generates Lorentz-invariance violation. This aether-like background induces a…
We present an exact black hole solution surrounded by massive vector fields predicted by Kaluza-Klein (KK) gravity. KK gravity in four dimensions (4D) is of particular interest, as it predicts a tower of particle states, including gravitons…
With one extra dimension, current high precision electroweak data constrain the masses of the first Kaluza-Klein excitations of the Standard Model gauge fields to lie above $\simeq 4$ TeV. States with masses not much larger than this should…
It has been recently observed that small violations of Lorentz invariance, of a type which may arise in quantum gravity, could explain both the observations of cosmic rays above the GZK cutoff and the observations of 20-TeV gamma rays from…
We examine the radiative corrections to an extension of the standard model containing a Lorentz-violating axial vector parameter. At second order in this parameter, the photon self-energy is known to contain terms that violate gauge…
The group of coordinate transformations for 5D noncompact Kaluza-Klein theory is broader than the 4D group for Einstein's general relativity. Therefore, a 4D quantity can take on different forms depending on the choice for the 5D…
We derive new improved constraints on the compactification scale of minimal 5-dimensional (5D) extensions of the Standard Model (SM) from electroweak and LEP2 data and estimate the reach of an e^+e^- linear collider such as TESLA. Our…