6,292 research outputs found
SU(N) Wigner-Racah algebra for the matrix of second moments of embedded Gaussian unitary ensemble of random matrices
Recently Pluhar and Weidenmueller [Ann. Phys. (N.Y.) Vol 297, 344 (2002)]
showed that the eigenvectors of the matrix of second moments of embedded
Gaussian unitary ensemble of random matrices generated by k-body interactions
(EGUE(k)) for m fermions in N single particle states are SU(N) Wigner
coefficients and derived also an expression for the eigenvalues. Going beyond
this work, we will show that the eigenvalues of this matrix are square of a
SU(N) Racah coefficient and thus the matrix of second moments of EGUE(k) is
solved completely by SU(N) Wigner-Racah algebra.Comment: 16 page
Comparison of mass limiting two-phase flow in a straight tube and in a nozzle
Mass-limiting and near mass-limiting two-phase flow in straight tube and nozzle of refrigerant flow loop syste
Angular-planar CMB power spectrum
Gaussianity and statistical isotropy of the Universe are modern cosmology's
minimal set of hypotheses. In this work we introduce a new statistical test to
detect observational deviations from this minimal set. By defining the
temperature correlation function over the whole celestial sphere, we are able
to independently quantify both angular and planar dependence (modulations) of
the CMB temperature power spectrum over different slices of this sphere. Given
that planar dependence leads to further modulations of the usual angular power
spectrum , this test can potentially reveal richer structures in the
morphology of the primordial temperature field. We have also constructed an
unbiased estimator for this angular-planar power spectrum which naturally
generalizes the estimator for the usual 's. With the help of a chi-square
analysis, we have used this estimator to search for observational deviations of
statistical isotropy in WMAP's 5 year release data set (ILC5), where we found
only slight anomalies on the angular scales and . Since this
angular-planar statistic is model-independent, it is ideal to employ in
searches of statistical anisotropy (e.g., contaminations from the galactic
plane) and to characterize non-Gaussianities.Comment: Replaced to match the published version. Journal-ref: Phys.Rev. D80
063525 (2009
Noncommuting spherical coordinates
Restricting the states of a charged particle to the lowest Landau level
introduces a noncommutativity between Cartesian coordinate operators. This idea
is extended to the motion of a charged particle on a sphere in the presence of
a magnetic monopole. Restricting the dynamics to the lowest energy level
results in noncommutativity for angular variables and to a definition of a
noncommuting spherical product. The values of the commutators of various
angular variables are not arbitrary but are restricted by the discrete
magnitude of the magnetic monopole charge. An algebra, isomorphic to angular
momentum, appears. This algebra is used to define a spherical star product.
Solutions are obtained for dynamics in the presence of additional angular
dependent potentials.Comment: 5 pages, RevTex4 fil
Polarized entangled Bose-Einstein condensation
We consider a mixture of two distinct species of atoms of pseudospin-1/2 with
both intraspecies and Interspecies spin-exchange interactions, and find all the
ground stats in a general case of the parameters in the effective Hamiltonian.
In general, corresponding to the two species and two pseudo-spin states, there
are four orbital wave functions into which the atoms condense. We find that in
certain parameter regimes, the ground state is the so-called polarized
entangled Bose-Einstein condensation, i.e. in addition to condensation of
interspecies singlet pairs, there are unpaired atoms with spins polarized in
the same direction. The interspecies entanglement and polarization
significantly affect the generalized Gross-Pitaevskii equations governing the
four orbital wave functions into which the atoms condense, as an interesting
interplay between spin and orbital degrees of freedom.Comment: 14 pages, received by PRA on 27 October 201
Thermodynamic depressions within cavities and cavitation inception in liquid hydrogen and liquid nitrogen Final report, 15 Jul. 1964 - 15 Dec. 1967
Thermodynamic depressions within cavities and cavitation inception in liquid hydrogen and nitrogen in transparent plastic venturi tube
Cavitation inception in liquid nitrogen and liquid hydrogen flowing in a venturi Interim report, 15 Jul. 1964 - 15 Jul. 1967
Cavitation characteristics of liquid hydrogen, and liquid nitrogen flow in plastic ventur
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