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We show the bounds on five- and six-dimensional Universal Extra Dimension models from the result of the Higgs boson searches at the Large Hadron Collider and electroweak precision measurement. The latest data released by the ATLAS and the CMS gives the lower bounds on Kaluza-Klein scale which are from 650 GeV to 1350 GeV depending on models from Higgs to diboson/diphoton decay signal. The Higgs production cross section can be enhanced by factor 1.5 in crude estimation, diphoton decay signal is suppressed about 10%. Electroweak precision measurement also gives the lower bounds as from 700 GeV to 1500 GeV.
We review the six dimensional universal extra dimension models compactified on the sphere $S^2$, the orbifold $S^2/Z_2$, and the projective sphere, which are based on the spontaneous compactification mechanism on the sphere. In particular, we spell o
We reconsider the constraints on Universal Extra Dimensions (UED) models arising from precision electroweak data. We take into account the subleading contributions from new physics (expressed in terms of the X,Y ... variables), as well as two loop co
We explore the properties of dark matter in theories with two universal extra dimensions, where the lightest Kaluza-Klein state is a spin-0 neutral particle, representing a six-dimensional photon polarized along the extra dimensions. Annihilation of
The usual universal extra dimensions scenario does not allow for single production of first level Kaluza-Klein (KK) excitations of matter due to the KK number conservation. However, if the matter fields are localized on a fat brane embedded in a high
The minimal Universal Extra Dimension scenario is highly constrained owing to opposing constraints from the observed relic density on the one hand, and the non-observation of new states at the LHC on the other. Simple extensions in five-dimensions ca