312 research outputs found
On iterated translated points for contactomorphisms of R^{2n+1} and R^{2n} x S^1
A point q in a contact manifold is called a translated point for a
contactomorphism \phi, with respect to some fixed contact form, if \phi (q) and
q belong to the same Reeb orbit and the contact form is preserved at q. The
problem of existence of translated points is related to the chord conjecture
and to the problem of leafwise coisotropic intersections. In the case of a
compactly supported contactomorphism of R^{2n+1} or R^{2n} x S^1 contact
isotopic to the identity, existence of translated points follows immediately
from Chekanov's theorem on critical points of quasi-functions and Bhupal's
graph construction. In this article we prove that if \phi is positive then
there are infinitely many non-trivial geometrically distinct iterated
translated points, i.e. translated points of some iteration \phi^k. This result
can be seen as a (partial) contact analogue of the result of Viterbo on
existence of infinitely many iterated fixed points for compactly supported
Hamiltonian symplectomorphisms of R^{2n}, and is obtained with generating
functions techniques in the setting of arXiv:0901.3112.Comment: 10 pages, revised version. I removed the discussion on linear growth
of iterated translated points, because it contained a mistake. To appear in
the International Journal of Mathematic
Determining the CP properties of the Higgs boson
The search and the probe of the fundamental properties of Higgs boson(s) and,
in particular, the determination of their charge conjugation and parity (CP)
quantum numbers, is one of the main tasks of future high-energy colliders. We
demonstrate that the CP properties of a Standard Model-like Higgs particle can
be unambiguously assessed by measuring just the total cross section and the top
polarization in associated Higgs production with top quark pairs in e+e-
collisions.Comment: 4 pages, revtex, uses axodraw (style file included in the submission
Electroweak Symmetry Breaking and Proton Decay in SO(10) SUSY-GUT with TeV W_R
In a recent paper, we proposed a new class of supersymmetric SO(10) models
for neutrino masses where the TeV scale electroweak symmetry is SU(2)_L\times
SU(2)_R\times U(1)_{B-L} making the associated gauge bosons W_R and Z'
accessible at the Large Hadron Collider. We showed that there exists a domain
of Yukawa coupling parameters and symmetry breaking patterns which give an
excellent fit to all fermion masses including neutrinos. In this sequel, we
discuss an alternative Yukawa pattern which also gives good fermion mass fit
and then study the predictions of both models for proton lifetime. Consistency
with current experimental lower limits on proton life time require the squark
masses of first two generations to be larger than ~ 1.2 TeV. We also discuss
how one can have simultaneous breaking of both SU(2)_R\times U(1)_{B-L} and
standard electroweak symmetries via radiative corrections.Comment: 31 pages, 5 figures, 4 tables
Neutrino Mass Hierarchy and neutron-anti-neutron Oscillation from Baryogenesis
It has been recently proposed that the matter-antimatter asymmetry of the
universe may have its origin in "post-sphaleron baryogenesis" (PSB). It is a
TeV scale mechanism that is testable at the LHC and other low energy
experiments. In this paper we present a theory of PSB within a quark-lepton
unified scheme based on the gauge group
that allows a direct connection between the baryon asymmetry and neutrino mass
matrix. The flavor changing neutral current constraints on the model allow
successful baryogenesis only for an inverted mass hierarchy for neutrinos,
which can be tested in the proposed long base line neutrino experiments. The
model also predicts observable neutron--antineutron oscillation accessible to
the next generation of experiments as well as TeV scale colored scalars within
reach of LHC.Comment: 23 pages and seven figures; Fifure 4 replaced; references updated;
typos correcte
Multi-Lepton Collider Signatures of Heavy Dirac and Majorana Neutrinos
We discuss the possibility of observing multi-lepton signals at the Large
Hadron Collider (LHC) from the production and decay of heavy Standard Model
(SM) singlet neutrinos added in extensions of SM to explain the observed light
neutrino masses by seesaw mechanism. In particular, we analyze two `smoking
gun' signals depending on the Dirac or Majorana nature of the heavy neutrino:
(i) for Majorana case, the same-sign di-lepton signal which can be used as a
probe of lepton-number violation, and (ii) for Dirac case, the tri-lepton
signal which conserves lepton number but may violate lepton flavor. Within a
minimal Left-Right symmetric framework in which these additional neutrino
states arise naturally, we find that in both cases, the signals can be
identified with virtually no background beyond a TeV, and the heavy gauge boson
W_R can be discovered in this process. This analysis also provides a direct way
to probe the nature of seesaw physics involving the SM singlets at TeV scale,
and in particular, to distinguish type-I seesaw with purely Majorana heavy
neutrinos from inverse seesaw with pseudo-Dirac counterparts.Comment: 19 pages, 7 figures; typo in eq. 5 fixed; matches published versio
Probing CP properties of the Higgs Boson via e<SUP>+</SUP>e<SUP>-</SUP>→tt̅φ
One of the main endeavors at future high-energy colliders is the search for the Higgs boson(s) and, once found, the probe of the fundamental properties. In particular, the charge conjugation and parity (CP) quantum numbers have to be determined. We show that these are unambiguously accessible at future e+ e- colliders through the measurement of the total cross section and the top polarization in associated Higgs production with top quark pairs
Americans' Views on Health Insurance at the End of a Turbulent Year
The Affordable Care Act's 2018 open enrollment period came at the end of a turbulent year in health care. The Trump administration took several steps to weaken the ACA's insurance marketplaces. Meanwhile, congressional Republicans engaged in a nine-month effort to repeal and replace the law's coverage expansions and roll back Medicaid. Nevertheless, 11.8 million people had selected plans through the marketplaces by the end of January, about 3.7 percent fewer than the prior year. There was an overall increase in enrollment this year in states that run their own marketplaces and a decrease in those states that rely on the federal marketplace.To gauge the perspectives of Americans on the marketplaces, Medicaid, and other health insurance issues, the Commonwealth Fund Affordable Care Act Tracking Survey interviewed a random, nationally representative sample of 2,410 adults ages 19 to 64 between November 2 and December 27, 2017, including 541 people who have marketplace or Medicaid coverage.The findings are compared to prior ACA tracking surveys, the most recent of which was fielded between March and June 2017. The survey research firm SSRS conducted the survey, which has an overall margin of error is +/– 2.7 percentage points at the 95 percent confidence level
Collective treatment of High Energy Thresholds in SUSY - GUTs
Supersymmetric GUTs are the most natural extension of the Standard model
unifying electroweak and strong forces. Despite their indubitable virtues,
among these the gauge coupling unification and the quantization of the electric
charge, one of their shortcomings is the large number of parameters used to
describe the high energy thresholds (HET), which are hard to handle. We present
a new method according to which the effects of the HET, in any GUT model, can
be described by fewer parameters that are randomly produced from the original
set of the parameters of the model. In this way, regions favoured by the
experimental data are easier to locate, avoiding a detailed and time consuming
exploration of the parameter space, which is multidimensional even in the most
economic unifying schemes. To check the efficiency of this method, we directly
apply it to a SUSY SO(10) GUT model in which the doublet-triplet splitting is
realized through the Dimopoulos-Wilczek mechanism. We show that the demand of
gauge coupling unification, in conjunction with precision data, locates regions
of the parameter space in which values of the strong coupling \astrong are
within the experimental limits, along with a suppressed nucleon decay, mediated
by a higgsino driven dimension five operators, yielding lifetimes that are
comfortably above the current experimental bounds. These regions open up for
values of the SUSY breaking parameters m_0, M_1/2 < 1 TeV being therefore
accessible to LHC.Comment: 21 pages, 8 figures, UA-NPPS/BSM-10/02 (added
Contact orderability up to conjugation
We study in this paper the remnants of the contact partial order on the
orbits of the adjoint action of contactomorphism groups on their Lie algebras.
Our main interest is a class of non-compact contact manifolds, called convex at
infinity.Comment: 28 pages, 1 figur
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