7,973 research outputs found
New constraints on R-parity violation from proton stability
We derive stringent upper bounds on all the -type
combinations from the consideration of proton stability, where
are baryon-number-violating trilinear couplings and
are lepton-number-violating bilinear mass parameters in a R-parity-violating
supersymmetric theory.Comment: 4 pages, Latex, uses axodraw.sty (in the revised version all
combinations of the form have been constrained, using
one-loop graphs) To appear in Phys. Lett.
Neutrino mass generation in the SO(4) model
Generation of neutrino mass in SO(4) model is proposed here. The algebraic
structure of SO(4) is same as to that of . It is
shown that the spontaneous symmetry breaking results three massive as well as
three massless gauge bosons. The standard model theory according to which there
exist three massive gauge bosons and a massless one is emerged from this model.
In the framework of a small Dirac neutrino mass is
derived. It is also shown that such mass term may vanish with a special choice.
The Majorana mass term is not considered here and thus in this model the
neutrino mass does not follow seesaw structure.Comment: 7 pages, no figur
Modified Higgs couplings and unitarity violation
Prompted by the recent observation of a Higgs-like particle at the CERN Large
Hadron Collider (LHC), we investigate a quantitative correlation between
possible departures of the gauge and Yukawa couplings of this particle from
their Standard Model expectations and the scale of unitarity violation in the
processes and .Comment: 6 pages, 6 eps figures, Arrayeq.sty attached; v2: minor updates,
version published: PRD 87 (2013) 011702(R), Rapid Communicatio
On certain Toeplitz operators and associated completely positive maps
We study Toeplitz operators with respect to a commuting -tuple of bounded
operators which satisfies some additional conditions coming from complex
geometry. Then we consider a particular such tuple on a function space. The
algebra of Toeplitz operators with respect to that particular tuple becomes
naturally homeomorphic to of a certain compact subset of . Dual Toeplitz operators are characterized. En route, we prove an
extension type theorem which is not only important for studying Toeplitz
operators, but also has an independent interest because dilation theorems do
not hold in general for .Comment: 25 pages. arXiv admin note: text overlap with arXiv:1706.0346
Analysing climate action plans of selected UK cities for their SDG alignment
In UK, the Climate change Act of 2008 has placed a binding target of reducing the net carbon emission in 2050 by at least 80% compared to the 1990 baseline. With a high share of urban population, the contribution of cities and urban areas towards climate change mitigation and adaptation becomes crucial. UK being a signatory to the Sustainable Development Goals (SDG) in 2016, there is a new emphasis on the sustainability of cities as well. In this paper, a preliminary analysis of climate action initiatives of three UK cities (Bristol, Leicester and Milton Keynes) and their alignment with the SDG is presented. We used a text mining approach to analyse the climate action plans and then use this to map the alignment with the SDGs. We find that climate action plans have not focused on the sustainable development goals or the SDGs and their focus remains limited mainly to mitigation activities through promotion of renewable energies at homes and in buildings and actions on transport. However, climate action plans could influence a significant number of SDGs and an integrated approach could be beneficial for the cities and their residents
Clusters of bound particles in the derivative delta-function Bose gas
In this paper we discuss a novel procedure for constructing clusters of bound
particles in the case of a quantum integrable derivative delta-function Bose
gas in one dimension. It is shown that clusters of bound particles can be
constructed for this Bose gas for some special values of the coupling constant,
by taking the quasi-momenta associated with the corresponding Bethe state to be
equidistant points on a single circle in the complex momentum plane. We also
establish a connection between these special values of the coupling constant
and some fractions belonging to the Farey sequences in number theory. This
connection leads to a classification of the clusters of bound particles
associated with the derivative delta-function Bose gas and allows us to study
various properties of these clusters like their size and their stability under
the variation of the coupling constant.Comment: 33 pages, 1 figure, minor typos correcte
Construction of some special subsequences within a Farey sequence
Recently it has been found that some special subsequences within a Farey
sequence play a crucial role in determining the ranges of coupling constant for
which quantum soliton states can exist for an integrable derivative nonlinear
Schrodinger model. In this article, we find a novel mapping which connects two
such subsequences belonging to Farey sequences of different orders. By using
this mapping, we construct an algorithm to generate all of these special
subsequences within a Farey sequence. We also derive the continued fraction
expansions for all the elements belonging to a subsequence and observe a close
connection amongst the corresponding expansion coefficients.Comment: latex, 8 page
Parameter estimates for fractional autoregressive spatial processes
A binomial-type operator on a stationary Gaussian process is introduced in
order to model long memory in the spatial context. Consistent estimators of
model parameters are demonstrated. In particular, it is shown that
, where
denotes the long memory parameter.Comment: Published at http://dx.doi.org/10.1214/009053605000000589 in the
Annals of Statistics (http://www.imstat.org/aos/) by the Institute of
Mathematical Statistics (http://www.imstat.org
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