2,507 research outputs found
Group-theoretic restrictions on generation of CP-violation in multi-Higgs-doublet models
It has been known since decades that imposing a symmetry group G on the
scalar sector of multi-Higgs-doublet models has consequences for CP-violation.
In all examples of two- and three-Higgs-doublet models equipped with
symmetries, one observes the following intriguing property: if G prevents
explicit CP-violation (CPV), at least in the neutral Higgs sector, then it also
prevents spontaneous CPV, and if G allows explicit CPV, then it allows for
spontaneous CPV. One is led to conjecture that this is a general phenomenon. In
this paper, we prove this conjecture for any rephasing symmetry group G and any
number of doublets.Comment: 16 page
A Highly Predictive Ansatz for Leptonic Mixing and CP Violation
We suggest a simple highly predictive ansatz for charged lepton and light
neutrino mass matrices, based on the assumption of universality of Yukawa
couplings. Using as input the charged lepton masses and light neutrino masses,
the six parameters characterizing the leptonic mixing matrix , are
predicted in terms of a single phase , which takes a value around
. Correlations among variuos physical quantities are
obtained, in particular is predicted as a function of
, and , and
restricted to the range .Comment: 9 pages, 4 figure
CP Violation and Flavour Mixings in Orbifold GUTs
We address the flavour problem by incorporating the hypothesis of universal
strength of Yukawa couplings in the framework of a 5D GUT model compactified on
an orbifold. We show that a quantitatively
successful picture of fermion masses and mixings emerges from the interplay
between the bulk suppression factors of geometric origin and the phases of the
Yukawa matrices. We give an explicit example, where we obtain a good fit for
both the CKM and PMNS matrices.Comment: 8 pages, no figures; v2: minor changes, published in Phys Rev D
(Rapid Communication
Leptonic Invariants, Neutrino Mass-Ordering and the Octant of
We point out that leptonic weak-basis invariants are an important tool for
the study of the properties of lepton flavour models. In particular, we show
that appropriately chosen invariants can give a clear indication of whether a
particular lepton flavour model favours normal or inverted hierarchy for
neutrino masses and what is the octant of . These invariants can
be evaluated in any conveniently chosen weak-basis and can also be expressed in
terms of neutrino masses, charged lepton masses, mixing angles and CP violation
phases.Comment: 10 pages, no figure
Non-Factorizable Phases, Yukawa Textures and the Size of sin (2 beta)
We emphasize the crucial r\^ ole played by non-factorizable phases in the
analysis of the Yukawa flavour structure performed in weak bases with Hermitian
mass matrices and with vanishing entries. We show that non-factorizable
phases are important in order to generate a sufficiently large .
A method is suggested to reconstruct the flavour structure of Yukawa couplings
from input experimental data both in this Hermitian basis and in a
non-Hermitian basis with a maximal number of texture zeros. The corresponding
Froggatt--Nielsen patterns are presented in both cases.Comment: 15 pages, 3 figure
Higgs masses of the general 2HDM in the Minkowski-space formalism
We study the masses of the Higgs bosons in the most general two-Higgs-doublet
model in a basis-independent approach. We adapt the recently developed
Minkowski-space formalism to this problem and calculate traces of any power of
the mass-matrix in a compact and reparametrization-invariant form. Our results
can be used to gain insight into the dynamics of the scalar sector of the
general 2HDM.Comment: 14 pages, no figures; v2: reference added, misprints correcte
Minkowski space structure of the Higgs potential in 2HDM: II. Minima, symmetries, and topology
We continue to explore the consequences of the recently discovered Minkowski
space structure of the Higgs potential in the two-Higgs-doublet model. Here, we
focus on the vacuum properties. The search for extrema of the Higgs potential
is reformulated in terms of 3-quadrics in the 3+1-dimensional Minkowski space.
We prove that 2HDM cannot have more than two local minima in the orbit space
and that a twice-degenerate minimum can arise only via spontaneous violation of
a discrete symmetry of the Higgs potential. Investigating topology of the
3-quadrics, we give concise criteria for existence of non-contractible paths in
the Higgs orbit space. We also study explicit symmetries of the Higgs
potential/lagrangian and their spontaneous violation from a wider perspective
than usual.Comment: 27 pages, 5 figure
Rank/Rankl/opg: literature review
The discovery of the receptor activator of nuclear factor-kB (RANK)/RANK Ligand (RANKL)/osteoprotegerin (OPG) pathway contributed to the understanding of how bone formation and resorption were processed and regulated. RANKL and OPG are members of the tumor necrosis factor (TNF) and TNF receptor (TNFr) superfamilies, respectively, and binding to receptor activator of NF-kB (RANK) not only regulate osteoclast formation, activation and survival in normal bone modeling and remodeling, but also in several other pathologic conditions characterized by increased bone turnover. There is accumulating evidence of the potential role of OPG and RANKL in other tissues. Looking beyond the RANK/RANKL/OPG axis, Wingless (Wnt) pathway emerged as the osteoblast differentiation way, and also as a bone mass regulator. Researchers have been discovering new molecules and cytokines interactions. Altogether, data suggest that RANK/RANKL/OPG system could be targeted as a new treatment strategy in bone conditions. FREEDOM is the more recently published clinical trial about a RANKL-specific recombinant fully human monoclonal antibody (denosumab). OPG is also a potential innovative therapeutic option to be investigated.publishersversionpublishe
Atmosphere Control of a House
The project consists of the prototype of a house, whose atmosphere is controlled automatically. Specific Aims of learning: studying the Arduíno board and sensors for collecting information, controlling and executing actions, knowing the language of programming needed, searching for solutions to the challenges using technological resources. With this project, the students got toknow better the functioning of some sensors and how to apply them in other contexts. And they realized the importance of home automation in people's lives
Main consequences of IFRS adoption: analysis of existing literature and suggestions for further research
This study characterizes the results of scientific research on the effect of adopting the International Financial Reporting Standards (IFRS) that have been published in the most prestigious scientific journals in the field of accounting at the international level and it identifies avenues for further research. Based on the analysis of a set of 67 articles published by the accounting journals that make up the Social Sciences Citation Index (SSCI), published between 2000 and 2013, it is concluded that, as a general rule, IFRS adoption has a positive effect on information quality, the capital market, analysts' ability to predict, comparability, and information use. Nevertheless, this effect depends on some factors, such as country's characteristics (namely, the enforcement level) and companies' characteristics. Sharing rules is not, by itself, enough to create a common business language, and management incentives and institutional factors play a major role in framing the characteristics of financial reporting. Finally, some gaps are identified in the literature and avenues for further research are introduced.info:eu-repo/semantics/publishedVersio
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