3,599 research outputs found
On the numerical closeness of the effective phenomenological electroweak mixing angle and the \MS parameter
It happens that and are equal with 0.1% accuracy, though
they are split by radiative corrections and a natural estimate for their
difference is 1%. This degeneracy occurs only for value close to
170\GeV, so no deep physical reason can be attributed to it. However, another
puzzle of the Standard Model, the degeneracy of s_\Eff^2 and , is not
independent of the previous one since a good physical reason exists for
s_\Eff^2 and degeneracy. We present explicit formulas which relate
these three angles.Comment: 10 pages, latex, 3 figures included; published on MPLA. A few
numerical estimates are improved; journal-ref is adde
Raising the Higgs mass with Yukawa couplings for isotriplets in vector-like extensions of minimal supersymmetry
Extra vector-like matter with both electroweak-singlet masses and large
Yukawa couplings can significantly raise the lightest Higgs boson mass in
supersymmetry through radiative corrections. I consider models of this type
that involve a large Yukawa coupling between weak isotriplet and isodoublet
chiral supermultiplets. The particle content can be completed to provide
perturbative gauge coupling unification, in several different ways. The impact
on precision electroweak observables is shown to be acceptably small, even if
the new particles are as light as the current experimental bounds of order 100
GeV. I study the corrections to the lightest Higgs boson mass, and discuss the
general features of the collider signatures for the new fermions in these
models.Comment: 30 page
On the classification of scalar evolutionary integrable equations in dimensions
We consider evolutionary equations of the form where
is the nonlocality, and the right hand side is polynomial
in the derivatives of and . The recent paper \cite{FMN} provides a
complete list of integrable third order equations of this kind. Here we extend
the classification to fifth order equations. Besides the known examples of
Kadomtsev-Petviashvili (KP), Veselov-Novikov (VN) and Harry Dym (HD) equations,
as well as fifth order analogues and modifications thereof, our list contains a
number of equations which are apparently new. We conjecture that our examples
exhaust the list of scalar polynomial integrable equations with the nonlocality
. The classification procedure consists of two steps. First, we classify
quasilinear systems which may (potentially) occur as dispersionless limits of
integrable scalar evolutionary equations. After that we reconstruct dispersive
terms based on the requirement of the inheritance of hydrodynamic reductions of
the dispersionless limit by the full dispersive equation
Two-dimensional algebro-geometric difference operators
A generalized inverse problem for a two-dimensional difference operator is
introduced. A new construction of the algebro-geometric difference operators of
two types first considered by I.M.Krichever and S.P.Novikov is proposedComment: 11 pages; added references, enlarged introduction, rewritten abstrac
Algebras with Operator and Campbell--Hausdorff Formula
We introduce some new classes of algebras and estabilish in these algebras
Campbell--Hausdorff like formula. We describe the application of these
constructions to the problem of the connectivity of the Feynman graphs
corresponding to the Green functions in Quantum Fields Theory.Comment: 12 page
Active frequency-dividing filters
The method of synthesis of analog frequency-dividing devices on the basis of wave filters has been offered. Various variants of configurations of such filters are considered. It is shown that frequency-dividing filters synthesized according to the offered method, have the minimal order
The New Fat Higgs: Slimmer and More Attractive
In this paper we increase the MSSM tree level higgs mass bound to a value
that is naturally larger than the LEP-II search constraint by adding to the
superpotential a term, as in the NMSSM, and UV
completing with new strong dynamics {\it before} becomes
non-perturbative. Unlike other models of this type the higgs fields remain
elementary, alleviating the supersymmetric fine-tuning problem while
maintaining unification in a natural way.Comment: 14 pages and 2 figures. Added references and updated argument about
constraints from reheating temperatur
Topological Phenomena in the Real Periodic Sine-Gordon Theory
The set of real finite-gap Sine-Gordon solutions corresponding to a fixed
spectral curve consists of several connected components. A simple explicit
description of these components obtained by the authors recently is used to
study the consequences of this property. In particular this description allows
to calculate the topological charge of solutions (the averaging of the
-derivative of the potential) and to show that the averaging of other
standard conservation laws is the same for all components.Comment: LaTeX, 18 pages, 3 figure
The role of fragmentation in interaction of meteoroids with the Earth's atmosphere
As a rule, when analyzing the mechanism of quasi continuous fragmentation (QCF) it is assumed that fragments separated from the parent meteoroid (PM) are of equal initial mass. In reality, this may not be so. A major difficulty is the lack of observational data on the function of the fragment initial mass distribution and so one must resort to theoretical modeling. A discrete distribution is considered which excluded to a certain extent some mathematical difficulties. The calculation results are given and discussed
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