77,528 research outputs found
An Improved General E-unification Method
A generalization of Paramodulation is defined and shown to lead to a complete E-Unification method for arbitrary equational theories E. The method is defined in term of transformations on systems, building upon and refining results of Gallier and Snyder
A refined version of general E-unification
Transformation--based systems for general E-unification were first investigated by Gallier and Snyder. Their system extends the well--known rules for syntactic unification by Lazy Paramodulation, thus coping with the equational theory. More recently, Dougherty and Johann improved on this method by giving a restriction of the Lazy Paramodulation inferences. In this paper, we show that their system can be further improved by a stronger restriction on the applicability of Lazy Paramodulation. It turns out that the framework of proof transformations provides an elegant and natural means for proving completeness of the inference system
Reduction of Couplings in Quantum Field Theories with applications in Finite Theories and the MSSM
We apply the method of reduction of couplings in a Finite Unified Theory and
in the MSSM. The method consists on searching for renormalization group
invariant relations among couplings of a renormalizable theory holding to all
orders in perturbation theory. It has a remarkable predictive power since, at
the unification scale, it leads to relations between gauge and Yukawa couplings
in the dimensionless sectors and relations involving the trilinear terms and
the Yukawa couplings, as well as a sum rule among the scalar masses and the
unified gaugino mass in the soft breaking sector. In both the MSSM and the FUT
model we predict the masses of the top and bottom quarks and the light Higgs in
remarkable agreement with the experiment. Furthermore we also predict the
masses of the other Higgses, as well as the supersymmetric spectrum, both being
in very confortable agreement with the LHC bounds on Higgs and supersymmetric
particles.Comment: 18 pages, 4 figures. To appear in the proceedings of LT-10, Varna.
Based on invited talks given at: LT-10, Varna; PACT-2013, Madrid; SQS'2013,
Dubna; CORFU 2013, Corfu, and in several invited seminar
Removing the gauge parameter dependence of the effective potential by a field redefinition
The gauge parameter dependence of the effective potential is determined by
partial differential equations involving also the Higgs boson field expectation
value. Solving these equations by the method of characteristics leads to
complete elimination of the gauge parameter dependence of the effective
potential. The construction is carried out in the case of the standard model of
electroweak unification for the renormalization group improved effective
potential up to the next-leading logarithmic order.Comment: 17 page
Focus Point Supersymmetry: Proton Decay, Flavor and CP Violation, and the Higgs Boson Mass
In focus point supersymmetry, all squarks and sleptons, including those of
the third generation, have multi-TeV masses without sacrificing naturalness. We
examine the implications of this framework for low energy constraints and the
light Higgs boson mass. Undesirable contributions to proton decay and electric
dipole moments, generic in many supersymmetric models, are strongly suppressed.
As a result, the prediction for alpha_s in simple grand unified theories is 3
to 5 standard deviations closer to the experimental value, and the allowed
CP-violating phases are larger by one to two orders of magnitude. In addition,
the very heavy top and bottom squarks of focus point supersymmetry naturally
produce a Higgs boson mass at or above 115 GeV without requiring heavy
gauginos. We conclude with an extended discussion of issues related to the
definition of naturalness and comment on several other prescriptions given in
the literature.Comment: 31 pages, 10 figures, references added, version to appear in Phys.
Rev.
Yukawa Quasi-Unification
We construct concrete supersymmetric grand unified theories based on the
Pati-Salam gauge group SU(4)_c x SU(2)_L x SU(2)_R which naturally lead to a
moderate violation of "asymptotic" Yukawa unification and thus can allow an
acceptable b-quark mass even with universal boundary conditions. We consider
the constrained minimal supersymmetric standard model which emerges from one of
these theories with a deviation from Yukawa unification which is adequate for
mu>0. We show that this model possesses a wide and natural range of parameters
which is consistent with the data on b --> s gamma, the muon anomalous magnetic
moment, the cold dark matter abundance in the universe, and the Higgs boson
masses. The lightest supersymmetric particle can be as light as about 107 GeV.Comment: 27 pages including 10 figures, Revtex, minor corrections, version to
appear in Nucl. Phys.
A note on the RG flow in (N=1, D=4) Supergravity and applications to Z_3 orbifold/orientifold compactification
We apply the standard approach of RG flow for the gauge couplings in N=1 D=4
Supergravity to show how to match its results with the heterotic orbifold
and Type IIB orientifold-based models. Using only supergravity, anomaly
cancellation and the requirement of unification we determine the part of the
K\"ahler potential of the model invariant under the symmetries of the model.
For heterotic orbifolds/type IIB orientifolds, this shows that the lowest order
K\"ahler term of the dilaton has the structure in agreement
with string calculations. The structure of the holomorphic coupling is also
found from arguments of unification and anomaly cancellation under the
conjectured symmetries of the models. A consequence of the
latter is that in the case of the orientifold the holomorphic coupling
necessarily contains a part with coefficient proportional to the one loop beta
function, in agreement with string calculations which do not however assume
this symmetry. This gives circumstantial evidence for the existence of this
symmetry at string level in orientifold. Finally, we comment on the
values of the unification scale and examine the possibility of mirage
unification in which the effective unification scale may be situated far above
the string scale.Comment: 17 pages, LaTe
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