9,010 research outputs found
Dynamical Electroweak Symmetry Breaking in SO(5)xU(1) Gauge-Higgs Unification with Top and Bottom Quarks
An SO(5)xU(1) gauge-Higgs unification model in the Randall-Sundrum warped
space with top and bottom quarks is constructed. Additional fermions on the
Planck brane make exotic particles heavy by effectively changing boundary
conditions of bulk fermions from those determined by orbifold conditions. Gauge
couplings of a top quark multiplet trigger electroweak symmetry breaking by the
Hosotani mechanism, simultaneously giving a top quark the observed mass. The
bottom quark mass is generated by combination of brane interactions and the
Hosotani mechanism, where only one ratio of brane masses is relevant when the
scale of brane masses is much larger than the Kaluza-Klein scale (\sim 1.5
TeV). The Higgs mass is predicted to be 49.9 (53.5) GeV for the warp factor
10^{15} (10^{17}). The Wilson line phase turns out \pi/2 and the Higgs
couplings to W and Z vanish so that the LEP2 bound for the Higgs mass is
evaded. In the flat spacetime limit the electroweak symmetry is unbroken.Comment: 35 pages, 2 figures. A few corrections are mad
Renormalizability of Massive Gravity in Three Dimensions
We discuss renormalizability of a recently established, massive gravity
theory with particular higher derivative terms in three space-time dimensions.
It is shown that this massive gravity is certainly renormalizable as well as
unitary, so it gives us a physically interesting toy model of perturbative
quantum gravity in three dimensions.Comment: 13 pages, no figure
Locally Localized Gravity Models in Higher Dimensions
We explore the possibility of generalizing the locally localized gravity
model in five space-time dimensions to arbitrary higher dimensions. In a
space-time with negative cosmological constant, there are essentially two kinds
of higher-dimensional cousins which not only take an analytic form but also are
free from the naked curvature singularity in a whole bulk space-time. One
cousin is a trivial extension of five-dimensional model, while the other one is
in essence in higher dimensions. One interesting observation is that in the
latter model, only anti-de Sitter () brane is physically meaningful
whereas de Sitter () and Minkowski () branes are dismissed.
Moreover, for brane in the latter model, we study the property of
localization of various bulk fields on a single brane. In particular, it is
shown that the presence of the brane cosmological constant enables bulk gauge
field and massless fermions to confine to the brane only by a gravitational
interaction. We find a novel relation between mass of brane gauge field and the
brane cosmological constant.Comment: 20 pages, LaTex 2e, revised version (to appear in Phys. Rev. D
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