7,542 research outputs found
Does gravitational wave propagate in the five dimensional space-time with Kaluza-Klein monopole?
The behavior of small perturbations around the Kaluza-Klein monopole in the
five dimensional space-time is investigated. The fact that the odd parity
gravitational wave does not propagate in the five dimensional space-time with
Kaluza-Klein monopole is found provided that the gravitational wave is constant
in the fifth direction.Comment: 10 @ages, LATE
On Forward J/\psi Production at Fermilab Tevatron
The D0 Collaboration has recently reported the measurement of J/\psi
production at low angle. We show here that the inclusion of color octet
contributions in any framework is able to reproduce this data.Comment: 1 page, Revtex, uses epsfig.sty, 2 postscript figure
Correlations of the elements of the neutrino mass matrix
Assuming Majorana nature of neutrinos, we re-investigate, in the light of the
recent measurement of the reactor mixing angle, the allowed ranges for the
absolute values of the elements of the neutrino mass matrix in the basis where
the charged-lepton mass matrix is diagonal. Apart from the derivation of upper
and lower bounds on the values of the matrix elements, we also study their
correlations. Moreover, we analyse the sensitivity of bounds and correlations
to the global fit results of the neutrino oscillation parameters which are
available in the literature.Comment: 37 pages, 146 figures, minor corrections, 17 additional figures,
version for publication in JHE
Chiral constituent quark model and the coupling strength of eta'
Using the latest data pertaining to \bar u-\bar d asymmetry and the spin
polarization functions, detailed implications of the possible values of the
coupling strength of the singlet Goldstone boson \eta' have been investigated
in the \chiCQM with configuration mixing. Using \Delta u, \Delta_3, \bar u-\bar
d and \bar u/\bar d, the possible ranges of the coupling parameters a, \alpha^
2, \beta^ 2 and \zeta^ 2, representing respectively the probabilities of
fluctuations to pions, K, \eta and \eta^{'}, are shown to be 0.10 \lesssim a
\lesssim 0.14, 0.2\lesssim \alpha \lesssim 0.5, 0.2\lesssim \beta \lesssim 0.7
and 0.10 lesssim |\zeta| \lesssim 0.70. To constrain the coupling strength of
\eta', detailed fits have been obtained for spin polarization functions, quark
distribution functions and baryon octet magnetic moments corresponding to the
following sets of parameters: a=0.1, \alpha=0.4, \beta=0.7, |\zeta|=0.65 (Case
I); a=0.1, \alpha=0.4, \beta=0.6, |\zeta|=0.70 (Case II); a=0.14, \alpha=0.4,
\beta=0.2, \zeta=0 (Case III) and a=0.13, \alpha=\beta=0.45, |\zeta|=0.10 (Case
IV). Case I represents the calculations where a is fixed to be 0.1, in
accordance with earlier calculations, whereas other parameters are treated free
and the Case IV represents our best fit. The fits clearly establish that a
small non-zero value of the coupling of \eta' is preferred over the higher
values of \eta' as well as when \zeta=0, the latter implying the absence of
\eta' from the dynamics of \chiCQM. Our best fit achieves an overall excellent
fit to the data, in particular the fit for \Delta u, \Delta d, \Delta_8 as well
as the magnetic moments \mu_{n}, \mu_{\Sigma^-}, \mu_{\Sigma^+} and \mu_{\Xi^-}
is almost perfect, the \mu_{\Xi^-} being a difficult case for most of the
similar calculations.Comment: 8 RevTeX pages, 2 Tables, Revised version to appear in Int.J.Mod.Phys
Modified Wandzura-Wilczek Relation with the Nachtmann Variable
If one retains M^2/Q^2 terms in the kinematics, the Nachtmann variable \xi
seems to be more appropriate to describe deep inelastic lepton-nucleon
scattering. Up to the first power of M^2/Q^2, a modified Wandzura-Wilczek
relation with respect to \xi was derived. Kinematical correction factors are
given as functions of \xi and Q^2. A comparison of the modified g_2^WW(\xi) and
original g_2^WW(x) with the most recent g_2 data is shown.Comment: 10 pages, 3 figures, revised version with minor correction
Journal Staff
A time-dependent coordinate transformation of a constant coeffcient hyperbolic equation which results in a variable coeffcient problem is considered. By using the energy method, we derive well-posed boundary conditions for the continuous problem. It is shown that the number of boundary conditions depend on the coordinate transformation. By using Summation-by-Parts (SBP) operators for the space discretization and weak boundary conditions, an energy stable finite dieffrence scheme is obtained. We also show how to construct a time-dependent penalty formulation that automatically imposes the right number of boundary conditions. Numerical calculations corroborate the stability and accuracy of the approximations
An Admiralty for Asia: Isaac le Maire and conflicting conceptions about the corporate governance of the VOC
The Dutch East India Company or VOC in 1602 showed many characteristics of modern corporations, including limited liability, freely transferable shares, and well-defined managerial functions. However, we challenge the notion of the VOC as the precursor of modern corporations to argue that the company was a hybrid, combining elements from traditional partnerships with a governance structure modeled on existing public-private partnerships. The company’s charter r
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