286 research outputs found
D-string fluid in conifold: II. Matrix model for D-droplets on S^{3} and S^{2}
Motivated by similarities between Fractional Quantum Hall (FQH) systems and
aspects of topological string theory on conifold, we continue in the present
paper our previous study (hep-th/0604001, hep-th/0601020) concerning FQH
droplets on conifold. Here we focus our attention on the conifold sub-varieties
\textbf{\}and\textbf{\} and study the non
commutative quantum dynamics of D1 branes wrapped on a circle. We give a matrix
model proposal for FQH droplets of point like particles on
\textbf{\}and\textbf{\} with filling fraction
. We show that the ground state of droplets on carries an isospin and gives remarkably
rise to droplets on with Cartan-Weyl charge .Comment: 25 pages, one figur
't Hooft lines of ADE-type and Topological Quivers
We investigate 4D Chern-Simons theory with ADE gauge symmetries in the
presence of interacting Wilson and 't Hooft line defects. We analyse the
intrinsic properties of these lines' coupling and explicate the building of
oscillator-type Lax matrices verifying the RLL integrability equation. We
propose gauge quiver diagrams Q encoding the topological data
carried by the Lax operators and give several examples where Darboux
coordinates are interpreted in terms of topological bi-fundamental matter. We
exploit this graphical description to give new results
regarding solutions in representations beyond the fundamentals of , and , and to classify the Lax operators
for simply laced symmetries in a unified E CS theory. For quick access, a
summary list of the leading topological quivers Q is given in
the conclusion section [Figures 29.(a-e), 30.(a-d) and 31.(a-d)].Comment: LaTeX, 74 pages, 32 figure
On Flavor Symmetry in Lattice Quantum Chromodynamics
Using a well established method to engineer non abelian symmetries in
superstring compactifications, we study the link between the point splitting
method of Creutz et al of refs [1,2] for implementing flavor symmetry in
lattice QCD; and singularity theory in complex algebraic geometry. We show
amongst others that Creutz flavors for naive fermions are intimately related
with toric singularities of a class of complex Kahler manifolds that are
explicitly built here. In the case of naive fermions of QCD, Creutz
flavors are shown to live at the poles of real 2-spheres and carry quantum
charges of the fundamental of . We show moreover that the two
Creutz flavors in Karsten-Wilczek model, with Dirac operator in reciprocal
space of the form , are related with the small resolution of conifold
singularity that live at . Other related features are also
studied.Comment: LaTex, 40 pages, 8 figure
Les facteurs prédictifs de morbimortalité chez les patients sous ballon de contre pulsion intra-aortique en chirurgie cardiaque
Le ballon de contre pulsion intra-aortique (BCPIA) est fréquemment utilisé en chirurgie cardiaque, comme moyen d'assistance circulatoire en cas de bas débit cardiaque. Il est d'intérêt clinique de déterminer les facteurs pronostiques chez les patients porteurs d'un BCPIA en chirurgie cardiaque, et qui restent un sujet rarement élucidé dans la littérature. L'objectif de notre travail est de déterminer les facteurs prédictifs de morbimortalitéchez les patients sous ballon de contre pulsion intraortique en périopératoire d'une chirurgie cardiaque. Il s'agit d'une étude rétrospective portant sur l'ensemble des patients opérés en chirurgie cardiaque sous circulation extracorporelle, et ayant bénéficiés de la mise en place d'un ballon de contre pulsion intra-aortique en périopératoire, au service de chirurgie cardiovasculaire de l'Hôpital Militaire Mohamed V de Rabat, entrele mois de janvier 2005 et le mois d'aout 20014. Soixante dix patients ont été inclus dans notre étude. En analyse univariée l'âge, la dyspnée de stade III et IV, l'insuffisance cardiaque, la présence d'un infarctus du myocarde, d'une coronaropathie mono et bitronculaire, les anomalies du doppler de trons supra-aortique et du membre inférieur, le caractère urgent de la chirurgie, la durée de la circulation extracorporelle, l'instabilité hémodynamique postopératoire, le saignement et l'insuffisance rénale postopératoire étaient statistiquement associés à une mortalité postopératoire élevée. La dyskinésie préopératoire et la sortie de circulation extracorporelle sous drogues étaient associées à une morbidité globale élevée. En analyse multi variée, seule l'âge, constituait un facteur de risque indépendant de mortalité dans notre série avec un Odds Ratio (OR): 1,89 ; un Intervalle de Confiance (IC) 95% de (1,52-4,97) et un p =0,045. Au terme de notre étude, le taux de mortalité était de 48,57% et de morbidité globale était de 87,1%. Il nous parait donc nécessaire pour diminuer l'incidence de cette morbimortalité dans notre population, d'agir sur les facteurs que nous jugeons modifiables tels l'amélioration de la fonction cardiaque préopératoire, l'optimisation de la fonction rénale, la réduction de la durée de CEC et le contrôle du saignement
Quadrupole Pairing Interaction and Signature Inversion
The signature inversion in the \pi h11/2 \otimes \nu h11/2 rotational bands
of odd-odd Cs and La isotopes and the \pi h11/2 \otimes \nu i13/2 bands of
odd-odd Tb, Ho and Tm nuclei is investigated using pairing and deformation self
consistent mean field calculations. The model can rather satisfactorily account
for the anomalous signature splitting, provided that spin assignments in som of
the bands are revised. Our calculations show that signature inversioncan appear
already at axially symmetric shapes. It is found that this is due to the
contribution of the \lambda\mu=22 component of the quadrupole pairing
interaction to the mean field potential.Comment: 17 pages, 14 figures, Nuclear Physics A in prin
On Black Attractors in 8D and Heterotic/Type IIA Duality
Motivated by the study of black attractors in 8D supergravity with 16
supersymmetries, we use the field theory approach and 8D supersymmetry with non
trivial central charges to shed light on the exact duality between heterotic
string on T^2 and type IIA on real connected and compact surfaces {\Sigma}2. We
investigate the two constraints that should be obeyed by {\Sigma}2 and give
their solutions in terms of intersecting 2-cycles as well their classification
using Dynkin diagrams of affine Kac-Moody algebras. It is shown as well that
the moduli space of these dual theories is given by
SO(1,1)x((SO(2,r+2))/(SO(2)xSO(r+2))) where r stands for the rank of the gauge
symmetry G_{r} of the 10D heterotic string on T^2. The remarkable cases
r=-2,-1,0 as well as other features are also investigated.Comment: LaTex, 18 pages, 2 figures, To appear in JHE
Toric Calabi-Yau supermanifolds and mirror symmetry
We study mirror symmetry of supermanifolds constructed as fermionic
extensions of compact toric varieties. We mainly discuss the case where the
linear sigma A-model contains as many fermionic fields as there are U(1)
factors in the gauge group. In the mirror super-Landau-Ginzburg B-model, focus
is on the bosonic structure obtained after integrating out all the fermions.
Our key observation is that there is a relation between the super-Calabi-Yau
conditions of the A-model and quasi-homogeneity of the B-model, and that the
degree of the associated superpotential in the B-model is given in terms of the
determinant of the fermion charge matrix of the A-model.Comment: 20 pages, v2: references adde
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