63 research outputs found
A test of the instanton vacuum chiral quark model with axial anomaly low-energy theorems
The QCD + QED axial anomaly low-energy theorems are applied to estimate the
accuracy of an instanton vacuum - based chiral quark model. The low-energy
theorems give an exact relation between the matrix elements of the gluon and
photon parts of the QCD + QED axial anomaly operator equation. The matrix
elements between vacuum and two photon states and between vacuum and two gluon
states are calculated for arbitrary N_f. It is shown that this model does
satisfy the low-energy theorems with an accuracy of . We estimate
also the contribution of the nonperturbative conversion of gluons into photons
to the decay and compare with experimental data.Comment: uudecode, gzip, latex, 11 pages, the text and the list of references
was slightly change
Optimization of Bell's Inequality Violation For Continuous Variable Systems
Two mode squeezed vacuum states allow Bell's inequality violation (BIQV) for
all non-vanishing squeezing parameter . Maximal violation occurs at
when the parity of either component averages to zero. For a
given entangled {\it two spin} system BIQV is optimized via orientations of the
operators entering the Bell operator (cf. S. L. Braunstein, A. Mann and M.
Revzen: Phys. Rev. Lett. {\bf68}, 3259 (1992)). We show that for finite
in continuous variable systems (and in general whenever the dimensionality of
the subsystems is greater than 2) additional parameters are present for
optimizing BIQV. Thus the expectation value of the Bell operator depends, in
addition to the orientation parameters, on configuration parameters.
Optimization of these configurational parameters leads to a unique maximal BIQV
that depends only on The configurational parameter variation is used
to show that BIQV relation to entanglement is, even for pure state, not
monotonic.Comment: An example added; shows that the amount of Bell's inequality
violation as a measure of entanglement is doubtfu
CPT theorem in a (5+1) Galilean space-time
We extend the 5-dimensional Galilean space-time to a (5+1) Galilean
space-time in order to define a parity transformation in a covariant manner.
This allows us to discuss the discrete symmetries in the Galilean space-time,
which is embedded in the (5+1) Minkowski space-time. We discuss the Dirac-type
field, for which we give the 8\times 8 gamma matrices explicitly. We
demonstrate that the CPT theorem holds in the (5+1) Galilean space-time.Comment: 11 pages, 0 figur
Noncommutative Geometry and Symplectic Field Theory
In this work we study representations of the Poincare group defined over
symplectic manifolds, deriving the Klein-Gordon and the Dirac equation in phase
space. The formalism is associated with relativistic Wigner functions; the
Noether theorem is derived in phase space and an interacting field, including a
gauge field, approach is discussed.Comment: To appear in Physics Letters
The deformation of the interacting nucleon in the Skyrme model
Changes in the nucleon shape are investigated by letting the nucleon deform
under the strong interactions with another nucleon. The parameters of the axial
deformations are obtained by minimizing the static energy of the two nucleon
system at each internucleon distance . It is shown that the intrinsic
quadrupole moment of the interacting proton, , is about at
distances near fm.Comment: 11 pages, uudecode, gzip, tar, latex, 3 eps figures, accepted for the
publication by Phys.Lett.
Chiral-Odd Structure Function h_1^D(x) and Tensor Charge of the Deuteron
The chiral-odd structure function h_{1}^D(x) and the tensor charge of the
deuteron are studied within the Bethe-Salpeter formalism for the deuteron
amplitude. Utilizing a simple model for the nucleon structure function, h_1^N,
h_1^D(x) is calculated and the nuclear effects are analyzed.Comment: 10 pages, plus 3 Postscript figure
Weak-field approximation of effective gravitational theory with local Galilean invariance
We examine the weak-field approximation of locally Galilean invariant
gravitational theories with general covariance in a -dimensional
Galilean framework. The additional degrees of freedom allow us to obtain
Poisson, diffusion, and Schr\"odinger equations for the fluctuation field. An
advantage of this approach over the usual -dimensional General
Relativity is that it allows us to choose an ansatz for the fluctuation field
that can accommodate the field equations of the Lagrangian approach to MOdified
Newtonian Dynamics (MOND) known as AQUAdratic Lagrangian (AQUAL). We
investigate a wave solution for the Schr\"odinger equations.Comment: 15 page
Generalized Statistics and High Tc Superconductivity
Introducing the generalized, non-extensive statistics proposed by
Tsallis[1988], into the standard s-wave pairing BCS theory of superconductivity
in 2D yields a reasonable description of many of the main properties of high
temperature superconductors, provided some allowance is made for non-phonon
mediated interactions.Comment: 14 pages, 5 figure
Non-linear Liouville and Shr\"odinger equations in phase space
Unitary representations of the Galilei group are studied in phase space, in
order to describe classical and quantum systems. Conditions to write in general
form the generator of time translation and Lagrangians in phase space are then
established. In the classical case, Galilean invariance provides conditions for
writing the Liouville operator and Lagrangian for non-linear systems. We
analyze, as an example, a generalized kinetic equation where the collision term
is local and non-linear. The quantum counter-part of such unitary
representations are developed by using the Moyal (or star) product. Then a
non-linear Schr\"odinger equation in phase space is derived and analyzed. In
this case, an association with the Wigner formalism is established, which
provides a physical interpretation for the formalism
Electromagnetic isoscalar rho-pi-gamma exchange current and the anomalous action
Using modern data, we first refit constants needed to complete an anomalous
pi-rho-omega-a_1 Lagrangian obtained within the approach of hidden local
symmetries. Then we derive from this Lagrangian electromagnetic isoscalar
rho-pi-gamma and rho-a_1-gamma currents needed in calculations of the deuteron
electromagnetic form factors at large momentum transfers.Comment: 16 pages, 1 figure, Latex, feynman, submitted to Nucl. Phys.
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