6,561 research outputs found
Generalised Jantzen filtration of Lie superalgebras I.
A Jantzen type filtration for generalised Verma modules of Lie superalgebras is introduced. In the case of type I Lie superalgebras, it is shown that the generalised Jantzen filtration for any Kac module is the unique Loewy filtration, and the decomposition numbers of the layers of the filtration are determined by the coefficients of inverse Kazhdan–Lusztig polynomials. Furthermore, the length of the Jantzen filtration for any Kac module is determined explicitly in terms of the degree of atypicality of the highest weight. These results are applied to obtain a detailed description of the submodule lattices of Kac modules
Extra boson mix with Z boson explaining the mass of W boson
We explore the possibility of explaining the W mass with an extra gauge boson
mixing with the Z boson at tree level. Extra boson mixing with Z boson will
change the expression of Z boson mass, thus altering the W boson mass. We
explore two models in this work. We find that in the Derivative Portal Dark
Matter model, there are parameters space which can give the observed W boson
mass. And in the U(1) extension model, the kinetic mixing between extra boson
and B boson can also predict the observed W boson mass. Both model indicate an
extra vector boson with best fit mass around 120 GeV.Comment: 12 pages, 3 figure
Microvascular autologous submandibular gland transplantation in severe cases of keratoconjunctivitis sicca
Dry eye syndrome is a relatively common disease of the tears and ocular surfaces that results in discomfort, visual disturbance, and tear film instability with possible damage to the ocular surfaces. Microvascular submandibular gland (SMG) transfer offers a surgical alternative for a permanent autologous substitution of tears using the basal secretion of a transplanted SMG. Long-term follow-up reveals that this technique is a lasting and effective solution for patients with severe dry eye syndrome. The uncomfortable symptoms were relieved, and the frequency of use of pharmaceutical tear substitutes was reduced. Objective examination showed significant improvement in tear film and some features of ocular surface such as breakup time of tear film and corneal staining. Patients may suffer from obstruction of Wharton's duct or epiphora after surgery. Activation of secretion-related receptors could improve the early hypofunction of the denervated SMG and prevent the duct obstruction. Reduction surgery, partial SMG transplantation, uses of atropine gel or Botulinum toxin A could be the choices of treatment for epiphora.PubMed0153
Testing weakest force with coldest spot
Ultra-cold atom experiment in space with microgravity allows for realization
of dilute atomic-gas Bose-Einstein condensate (BEC) with macroscopically large
occupation number and significantly long condensate lifetime, which allows for
a precise measurement on the shape oscillation frequency by calibrating itself
over numerous oscillation periods. In this paper, we propose to measure the
Newtonian gravitational constant via ultra-cold atom BEC with shape
oscillation, although it is experimentally challenging. We also make a
preliminary perspective on constraining the modified Newtonian potential such
as the power-law potential, Yukawa interaction, and fat graviton. A resolution
of frequency measurement of at most for the occupation
number , just one order above experimentally achievable number
, is feasible to constrain the modified Newtonian potential
with Yukawa interaction greatly beyond the current exclusion limits.Comment: v1, 10 pages, 3 figures; v2, references added, discussion extended
for enlarged parameter space of Yukawa interaction, version accepted by EPJ
Nano-Hertz gravitational waves from collapsing domain walls associated with freeze-in dark matter in light of pulsar timing array observations
Evidence for a stochastic gravitational wave background in the nHz frequency
band is recently reported by four pulsar timing array collaborations NANOGrav,
EPTA, CPTA, and PPTA. It can be interpreted by gravitational waves from
collapsing domain walls in the early universe. We assume such domain walls
arising from the spontaneous breaking of a symmetry in a scalar field
theory, where a tiny -violating potential is required to make domain walls
unstable. We propose that this -violating potential is radiatively induced
by a feeble Yukawa coupling between the scalar field and a fermion field, which
is also responsible for dark matter production via the freeze-in mechanism.
Combining the pulsar timing array data and the observed dark matter relic
density, we find that the model parameters can be narrowed down to small
ranges.Comment: 18 pages, 6 figure
The patterns of bacterial community and relationships between sulfate-reducing bacteria and hydrochemistry in sulfate-polluted groundwater of Baogang rare earth tailings
Hamiltonian type Lie bialgebras
We first prove that, for any generalized Hamiltonian type Lie algebra ,
the first cohomology group is trivial. We then show that
all Lie bialgebra structures on are triangular.Comment: LaTeX, 16 page
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