182 research outputs found
Soft Supersymmetry Breaking from Coset Space Dimensional Reduction
The Coset Space Dimensional Reduction scheme is briefly reviewed. Then a
ten-dimensional supersymmetric gauge theory is reduced over symmetric and
non-symmetric six-dimensional coset spaces. In general a four-dimensional
non-supersymmetric gauge theory is obtained in case the used coset space is
symmetric, while a softly broken supersymmetric gauge theory is obtained if the
used coset space is non-symmetric. In the process of exhibiting the above
properties we also present two attractive models, worth exploiting further,
which lead to interesting GUTs with three families in four dimensions.Comment: 16 pages, Contribution to SUSY01 Dubna Russia, CORFU2001 Corfu
Greece, SQS01 Karpacz Poland and I Summer School in Modern Mathematical
Physics Sokobanja Yugoslavi
Dimensional Reduction of ten-dimensional Supersymmetric Gauge Theories in the N=1, D=4 Superfield Formalism
A ten-dimensional supersymmetric gauge theory is written in terms of N=1, D=4
superfields. The theory is dimensionally reduced over six-dimensional coset
spaces. We find that the resulting four-dimensional theory is either a softly
broken N=1 supersymmetric gauge theory or a non-supersymmetric gauge theory
depending on whether the coset spaces used in the reduction are non-symmetric
or symmetric. In both cases examples susceptible to yield realistic models are
presented.Comment: 24 page
Confronting Finite Unified Theories with Low-Energy Phenomenology
Finite Unified Theories (FUTs) are N=1 supersymmetric Grand Unified
Theories that can be made all-loop finite. The requirement of all-loop
finiteness leads to a severe reduction of the free parameters of the theory
and, in turn, to a large number of predictions. FUTs are investigated in the
context of low-energy phenomenology observables. We present a detailed scanning
of the all-loop finite SU(5) FUTs, where we include the theoretical
uncertainties at the unification scale and we apply several phenomenological
constraints. Taking into account the restrictions from the top and bottom quark
masses, we can discriminate between different models. Including further
low-energy constraints such as B physics observables, the bound on the lightest
Higgs boson mass and the cold dark matter density, we determine the predictions
of the allowed parameter space for the Higgs boson sector and the
supersymmetric particle spectrum of the selected model.Comment: 25 pages, 8 figures. Discussion on models and on cold dark matter
constraint extended, references added. Version to appear in JHE
Finite Unified Theories confronted with low-energy phenomenology
Finite Unified Theories (FUTs) are N=1 supersymmetric Grand Unified Theories
that can be made all-loop finite. The requirement of all-loop finiteness leads
to a severe reduction of the free parameters of the theory and, in turn, to a
large number of predictions. Here SU(5) FUTs are investigated in the context of
low-energy phenomenology observables. We present a detailed scanning of these
FUTs, including theoretical uncertainties at the unification scale and applying
all phenomenological constraints. Taking into account the restrictions from the
top and bottom quark masses, we can discriminate between different models.
Including further low-energy constraints such as physics observables, the
bound on the lightest Higgs boson mass and the cold dark matter density, we
determine the predictions of the allowed parameter space for the Higgs boson
sector and the supersymmetric particle spectrum of the model.Comment: Submitted for the SUSY07 proceedings, 4 pages, LaTeX, 3 eps figures.
v2 one ref adde
Finite Unified Models
We present phenomenologically viable unified models which are finite
to all orders before the spontaneous symmetry breaking. In the case of two
models with three families the top quark mass is predicted to be 178.8 GeV.Comment: 13 pages, latex fil
Finite Theories after the discovery of a Higgs-like boson at the LHC
Finite Unified Theories (FUTs) are N = 1 supersymmetric Grand Unified
Theories (GUTs) which can be made finite to all-loop orders, based on the
principle of reduction of couplings, and therefore are provided with a large
predictive power. Confronting the predictions of SU(5) FUTs with the top and
bottom quark masses and other low-energy experimental constraints a light
Higgs-boson mass in the range M_h ~ 121-126 GeV was predicted, in striking
agreement with the recent discovery of a Higgs-like state around ~ 125.7 GeV at
ATLAS and CMS. Furthermore the favoured model, a finiteness constrained version
of the MSSM, naturally predicts a relatively heavy spectrum with coloured
supersymmetric particles above ~ 1.5 TeV, consistent with the non-observation
of those particles at the LHC. Restricting further the best FUT's parameter
space according to the discovery of a Higgs-like state and B-physics
observables we find predictions for the rest of the Higgs masses and the
s-spectrum.Comment: 17 pages, 4 figures. arXiv admin note: substantial text overlap with
arXiv:0712.363
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