14,785 research outputs found
Inductive Algebras for Finite Heisenberg Groups
A characterization of the maximal abelian sub-algebras of matrix algebras
that are normalized by the canonical representation of a finite Heisenberg
group is given. Examples are constructed using a classification result for
finite Heisenberg groups.Comment: 5 page
Instability of Rotationally Tuned Dipolar Bose-Einstein Condensates
The possibility of effectively inverting the sign of the dipole-dipole
interaction, by fast rotation of the dipole polarization, is examined within a
harmonically trapped dipolar Bose-Einstein condensate. Our analysis is based on
the stationary states in the Thomas-Fermi limit, in the corotating frame, as
well as direct numerical simulations in the Thomas-Fermi regime, explicitly
accounting for the rotating polarization. The condensate is found to be
inherently unstable due to the dynamical instability of collective modes. This
ultimately prevents the realization of robust and long-lived rotationally tuned
states. Our findings have major implications for experimentally accessing this
regime.Comment: 9 pages with 5 figure
Upper-Ocean Response to Hurricane Ivan in a 1/25 Degrees Nested Gulf of Mexico HYCOM
[ 1] A 20-layer, 1/25 degrees nested Gulf of Mexico (GoM) Hybrid Coordinate Ocean Model (HYCOM) has been employed to examine the evolving three-dimensional ocean response to Hurricane Ivan during 14 - 16 September 2004. Results from several combinations of numerical experiments with and without assimilation of satellite-altimetry sea-surface height (SSH) are being analyzed and compared for the September 2004 hurricane period. A comparison of simulated zonal and meridional velocities using data assimilation shows improved agreement with profiler observations. The amplitude of the cold wake ( similar to 6 degrees C) produced by these simulations compared reasonably well with the observed changes in SST before and after the storm; however, the region of extreme cooling varied depending on the simulated location of the warm core eddy (WCE) that had detached from the Loop Current ( LC). While the simulated location of the WCE and LC in the assimilation runs agree better with satellite altimetry, the storm-induced SST cooling was 40% - 50% greater than the observed cooling. Overall, similar to 64% of the cooling was due to vertical mixing caused by turbulence generated from strong shear-stress across the base of the mixed layer. Vertical advection (upwelling) caused a significant portion of cooling (23.4%) in those runs that included data assimilation; a three fold increase from the nonassimilative runs (7%). This enhanced upper- ocean cooling was caused primarily by the prestorm thermal stratification; a shallower thermocline ( similar to 40 m) and a stronger upper- thermocline temperature gradient compared with the nonassimilative runs. In all the experiments the air-sea exchange was a small component of the mixed-layer heat budget which overall accounted for similar to 4
RESEARCH ON AYURVEDA DRUGS TOWARDS THE DRUG DEVELOPMENT FOR PLASMODIUM VIVAX MALARIA
Developing countries are more vulnerable to the Vector borne diseases, than developed countries. Incidence of Malaria is steadily increasing and number of deaths as well; is a serious problem in Africa; every five (20%) childhood deaths are due to the effects of the disease and every 30 seconds a child dies from malaria. The problem of Malaria acquired new dimensions such as resistance of vectors to chemical insecticides and drug resistance in strains of Plasmodium Vivax and Plasmodium Falciparum. These are the serious obstacles in the control of Malaria and hence there is a serious need to develop alternate strategies to control Malaria.Central Council for Research in Ayurvedic Sciences is carrying out clinical trial on different Vector Borne Diseases like Malaria, Filariasis etc since seventies. Trial carried out with herbal and herbo-mineral drugs like AYUSH-64, Saptaparnatwak ghanavati, Guduci satva, Spatika Bhasma, Kiratatiktadi compound, Parijatapatra ghanavati etc. on Plasmodium Vivax Malaria. The present paper deals with the details of those drugs and concludes the best drug for control of Malaria
Operator ordering in Two-dimensional N=1 supersymmetry with curved manifold
We investigate an operator ordering problem in two-dimensional N=1
supersymmetric model which consists of n real superfields. There arises an
operator ordering problem when the target space is curved. We have to fix the
ordering in quantum operator properly to obtain the correct supersymmetry
algebra. We demonstrate that the super-Poincar\'{e} algebra fixes the correct
operator ordering. We obtain a supercurrent with correct operator ordering and
a central extension of supersymmetry algebra.Comment: 7 page
Exact Schwarzschild-Like Solution for Yang-Mills Theories
Drawing on the parallel between general relativity and Yang-Mills theory we
obtain an exact Schwarzschild-like solution for SU(2) gauge fields coupled to a
massless scalar field. Pushing the analogy further we speculate that this
classical solution to the Yang-Mills equations shows confinement in the same
way that particles become confined once they pass the event horizon of the
Schwarzschild solution. Two special cases of the solution are considered.Comment: 11 pages LaTe
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