103,619 research outputs found
On the CR transversality of holomorphic maps into hyperquadrics
Let be a smooth Levi-nondegenerate hypersurface of signature
in with , and write for the standard
hyperquadric of the same signature in with .
Let be a holomorphic map sending into . Assume does
not send a neighborhood of in into . We show
that is necessarily CR transversal to at any point. Equivalently,
we show that is a local CR embedding from into .Comment: To appear in Abel Symposia, dedicated to Professor Yum-Tong Siu on
the occasion of his 70th birthda
Pion Form Factor in the Factorization Formalism
Based on the light-cone (LC) framework and the factorization formalism,
the transverse momentum effects and the different helicity components'
contributions to the pion form factor are recalculated. In
particular, the contribution to the pion form factor from the higher helicity
components (), which come from the spin-space Wigner
rotation, are analyzed in the soft and hard energy regions respectively. Our
results show that the right power behavior of the hard contribution from the
higher helicity components can only be obtained by fully keeping the
dependence in the hard amplitude, and that the dependence in LC wave
function affects the hard and soft contributions substantially. As an example,
we employ a model LC wave function to calculate the pion form factor and then
compare the numerical predictions with the experimental data. It is shown that
the soft contribution is less important at the intermediate energy region.Comment: 21 pages, 4 figure
Thermodynamic properties of interstitial elements in the refractory metals Semiannual report, 1 Dec. 1967 - 31 May 1968
Thermodynamic behavior of interstitial elements in Mo, W, Nb, and T
Correlation effects in the ground state of trapped atomic Bose gases
We study the effects of many-body correlations in trapped ultracold atomic
Bose gases. We calculate the ground state of the gas using a ground-state
auxiliary-field quantum Monte Carlo (QMC) method [Phys. Rev. E 70, 056702
(2004)]. We examine the properties of the gas, such as the energetics,
condensate fraction, real-space density, and momentum distribution, as a
function of the number of particles and the scattering length. We find that the
mean-field Gross-Pitaevskii (GP) approach gives qualitatively incorrect result
of the kinetic energy as a function of the scattering length. We present
detailed QMC data for the various quantities, and discuss the behavior of GP,
modified GP, and the Bogoliubov method under a local density approximation.Comment: 11 pages, 12 figures, as typeset using REVTEX4. Submitted to Phys.
Rev.
Transverse momentum dependence in the perturbative calculation of pion form factor
By reanalysing transverse momentum dependence in the perturbative calculation
of pion form factor an improved expression of pion form factor which takes into
account the transverse momentum dependenc in hard scattering amplitude and
intrinsic transverse momentum dependence associated with pion wave functions is
given to leading order, which is available for momentum transfers of the order
of a few GeV as well as for . Our scheme can be extended to
evaluate the contributions to the pion form factor beyond leading order.Comment: 13 pages in LaTeX, plus 3 Postscript figure
- …