Related papers: Improved Bounds on Universal Extra Dimensions
Experimental limits on the violation of four-dimensional Lorentz invariance imply that noncommutativity among ordinary spacetime dimensions must be small. Noncommutativity among extra, compactified spatial dimensions, however, is far less…
The electroweak symmetry may be broken by a composite Higgs which arises naturally as a bound state of the top quark if the standard model gauge fields and fermions propagate in extra dimenions. The top quark mass and the Higgs mass can be…
We reconsider cosmological constraints on extra dimension theories from the excess production of Kaluza-Klein gravitons. We point out that, if the normalcy temperature is above 1 GeV, then graviton states produced at this temperature will…
We study the unitarity of the standard model (SM) in higher dimensions. We show that the essential features of SM unitarity remain after compactification, and place bounds on the highest Kaluza-Klein (KK) level N_KK and the Higgs mass m_H…
In Kaluza-Klein theories of low-scale quantum gravity, gravitons and isosinglet neutrinos may propagate in a higher-dimensional space with large compact dimensions, whereas all particles of the Standard Model are confined on a…
Recently there have been discussions about which complex metrics should be allowable in quantum gravity. These discussions assumed that the matter fields were real valued. We make the observation that for compactified solutions it makes…
The exclusive weak decay of $\Lambda_b \to \Lambda \gamma$ and $\Lambda_b \to \Lambda l^{+} l^{-}$ are investigated in the Applequist-Cheng-Dobrescu model, which is an extension of the standard model in presence of universal extra…
We consider a model where sterile neutrinos can propagate in a large compactified extra dimension (a) giving rise to Kaluza-Klein (KK) modes and the Standard Model left-handed neutrinos are confined to a 4-dimensional spacetime brane. The…
Effects of Kaluza-Klein excitations associated with extra dimensions with large radius compactifications on the Fermi constant are explored. It is shown that the current precision determinations of the Fermi constant, of the fine structure…
We reevaluate the thermal relic density of the Kaluza-Klein (KK) dark matter in universal extra dimension models. In particular, we consider the effect of the resonance caused by second KK particles on the density. We find that the…
We explicitly show that split-universal extra dimension (split-UED), a recently suggested extension of universal extra dimension (UED) model, can nicely explain recent anomalies in cosmic-ray positrons and electrons observed by PAMELA and…
In this work we discuss our consistent implementation of the minimal model of Universal Extra Dimensions in CalcHEP. We pay special attention to the gauge invariance issues that arise due to the incorporation of 5D quantum corrections.…
We study the power law running of gauge, Yukawa and quartic scalar couplings in the universal extra dimension scenario where the extra dimension is accessed by all the standard model fields. After compactifying on an $S_1 /Z_2$ orbifold, we…
In this letter, we present LHC limits on the minimal universal extra dimension (MUED) model from LHC Run 1 data and current limits from searches of the ongoing Run 2. Typical collider signals of the Kaluza-Klein (KK) states mimic generic…
Astrophysical bounds severely limit the possibility of observing collider signals of gravity with less than 3 flat extra dimensions. However, small distortions of the compactified space can lift the masses of the lightest graviton…
We calculate the production of massive Kaluza-Klein(KK) modes via nucleon-nucleon gravi-bremsstrahlung in the early universe. Overproduction of these states would result in early matter domination and therefore a low age for the universe so…
Dark matter kinetic decoupling involves elastic scattering of dark matter off of leptons and quarks in the early universe, the same process relevant for direct detection and for the capture rate of dark matter in celestial bodies; the…
Kaluza-Klein fields characterizing, from a four-dimensional viewpoint, the presence of compact universal extra dimensions would alter low-energy observables through effects determined by some compactification scale, $R^{-1}$, since the…
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…
The Generalized Uncertainty Principle (GUP) implies the existence of a physical minimum length scale $l_m$. In this scenario, black holes must have a radius larger than $l_m$. They are hotter and evaporate faster than in standard Hawking…