39,201 research outputs found
Relationships between geographic and inertial coordinates of position
Relationships between geographic and inertial coordinates of positio
Gluon Correlators in the Kogan-Kovner Model
The Lorentz-invariant gluon correlation functions, corresponding to scalar
and pseudo-scalar glueballs, are calculated for Kogan's and Kovner's
variational ansatz for the pure SU(N) Yang-Mills wavefunctional.
One expects that only one dynamical mass scale should be present in QCD; the
ansatz generates the expected scale for both glueballs, as well as an
additional scale for the scalar glueball. The additional mass scale must
therefore vanish, or be close to the expected one. This is shown to constrain
the nature of the phase transition in the Kogan-Kovner ansatz.Comment: 9 pages, no figure
The Determination of the `Diffusion Coefficients' and the Stellar Wind Velocities for X-Ray Binaries
The distribution of neutron stars (NS's) is determined by stationary solution
of the Fokker-Planck equation. In this work using the observed period changes
for four systems: Vela X-1, GX 301-2, Her X-1 and Cen X-3 we determined D, the
'diffusion coefficient',-parameter from the Fokker-Planck equation. Using
strong dependence of D on the velocity for Vela X-1 and GX 301-2, systems
accreting from a stellar wind, we determined the stellar wind velocity. For
different assumptions for a turbulent velocity we obtained . It is in good agreement with the stellar wind velocity determined by
other methods. We also determined the specific characteristic time scales for
the 'diffusion processes' in X-ray pulsars. It is of order of 200 sec for
wind-fed pulsars and 1000-10000 sec for the disk accreting systems.Comment: 8 pages, Latex, no figures, accepted for publication to Astronomical
and Astrophysical Transactions (1995). Admin note 20Feb2000: original
(broken) version now paper.tex.orig in source; fixed version with two bad
equations set in verbatim used for PS, paper.tex in sourc
Riemannian submersions from almost contact metric manifolds
In this paper we obtain the structure equation of a contact-complex
Riemannian submersion and give some applications of this equation in the study
of almost cosymplectic manifolds with Kaehler fibres.Comment: Abh. Math. Semin. Univ. Hamb., to appea
A new class of sum rules for products of Bessel functions
In this paper we derive a new class of sum rules for products of the Bessel
functions of first kind. Using standard algebraic manipulations we extend some
of the well known properties of . Some physical applications of the
results are also discussed. A comparison with the Newberger[J. Math. Phys.
\textbf{23} (1982) 1278] sum rules is performed on a typical example.Comment: Published in Journal of Mathematical Physics, 9 pages, no picture
Curved planar quantum wires with Dirichlet and Neumann boundary conditions
We investigate the discrete spectrum of the Hamiltonian describing a quantum
particle living in the two-dimensional curved strip. We impose the Dirichlet
and Neumann boundary conditions on opposite sides of the strip. The existence
of the discrete eigenvalue below the essential spectrum threshold depends on
the sign of the total bending angle for the asymptotically straight strips.Comment: 7 page
Scalar Casimir effect between two concentric D-dimensional spheres
The Casimir energy for a massless scalar field between the closely spaced two
concentric D-dimensional (for D>3) spheres is calculated by using the mode
summation with contour integration in the complex plane of eigenfrequencies and
the generalized Abel-Plana formula for evenly spaced eigenfrequency at large
argument. The sign of the Casimir energy between closely spaced two concentric
D-dimensional spheres for a massless scalar field satisfying the Dirichlet
boundary conditions is strictly negative. The Casimir energy between D-1
dimensional surfaces close to each other is regarded as interesting both by
itself and as the key to describing of stability of the attractive Casimir
force. PACS number(s): 03.70.+k, 11.10.Kk, 11.10.Gh, 03.65.GeComment: 14 pages. arXiv admin note: substantial text overlap with
arXiv:1207.418
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