1,965 research outputs found
Key features of the TMD soft-factor structure
We show that the geometry of the Wilson lines, entering the operator
definition of the transverse-momentum dependent parton distributions and that
of the soft factor, follows from the kinematics of the underlying physical
process in conjunction with the gauge invariance of the QCD Lagrangian. We
demonstrate our method in terms of concrete examples and determine the paths of
the associated Wilson lines. The validation of the factorization theorem in our
approach is postponed to future work.Comment: 10 pages, 2 figures. Invited contribution presented by the first
author at the Lightcone 2013+ Conference, Skiathos, Greece, 20-24 May, 2013.
Matches version to appear in Few Body System
Stable autosolitons in dispersive media with saturable gain and absorption
We introduce the simplest one-dimensional model of a dispersive optical
medium with saturable dissipative nonlinearity and filtering (dispersive loss)
which gives rise to stable solitary pulses (autosolitons). In the particular
case when the dispersive loss is absent, the same model may also be interpreted
as describing a stationary field in a planar optical waveguide with uniformly
distributed saturable gain and absorption. In a certain region of the model's
parameter space, two coexisting solitary-pulse solutions are found numerically,
one of which may be stable. Solving the corresponding linearized eigenvalue
problem, we identify stability borders for the solitary pulses in their
parametric plane. Beyond one of the borders, the symmetric pulse is destroyed
by asymmetric perturbations, and at the other border it undergoes a Hopf
bifurcation, which may turn it into a breather.Comment: A latex text file and four ps files with figures. Physics Letters A,
in pres
Discretized rotation has infinitely many periodic orbits
For a fixed k in (-2,2), the discretized rotation on Z^2 is defined by
(x,y)->(y,-[x+ky]). We prove that this dynamics has infinitely many periodic
orbits.Comment: Revised after referee reports, and added a quantitative statemen
Delayed feedback control of self-mobile cavity solitons in a wide-aperture laser with a saturable absorber
We investigate the spatiotemporal dynamics of cavity solitons in a broad area
vertical-cavity surface-emitting laser with saturable absorption subjected to
time-delayed optical feedback. Using a combination of analytical, numerical and
path continuation methods we analyze the bifurcation structure of stationary
and moving cavity solitons and identify two different types of traveling
localized solutions, corresponding to slow and fast motion. We show that the
delay impacts both stationary and moving solutions either causing drifting and
wiggling dynamics of initially stationary cavity solitons or leading to
stabilization of intrinsically moving solutions. Finally, we demonstrate that
the fast cavity solitons can be associated with a lateral mode-locking regime
in a broad-area laser with a single longitudinal mode
A relativistic action-at-a-distance description of gravitational interactions?
It is shown that certain aspects of gravitation may be described using a
relativistic action-at-a-distance formulation. The equations of motion of the
model presented are invariant under Lorentz transformations and agree with the
equations of Einstein's theory of General Relativity, at the first
Post-Newtonian approximation, for any number of interacting point masses
Zeta Nonlocal Scalar Fields
We consider some nonlocal and nonpolynomial scalar field models originated
from p-adic string theory. Infinite number of spacetime derivatives is
determined by the operator valued Riemann zeta function through d'Alembertian
in its argument. Construction of the corresponding Lagrangians L starts
with the exact Lagrangian for effective field of p-adic tachyon
string, which is generalized replacing p by arbitrary natural number n and then
taken a sum of over all n. The corresponding new objects we
call zeta scalar strings. Some basic classical field properties of these fields
are obtained and presented in this paper. In particular, some solutions of the
equations of motion and their tachyon spectra are studied. Field theory with
Riemann zeta function dynamics is interesting in its own right as well.Comment: 13 pages, submitted to Theoretical and Mathematical Physic
On p-Adic Sector of Adelic String
We consider construction of Lagrangians which are candidates for p-adic
sector of an adelic open scalar string. Such Lagrangians have their origin in
Lagrangian for a single p-adic string and contain the Riemann zeta function
with the d'Alembertian in its argument. In particular, we present a new
Lagrangian obtained by an additive approach which takes into account all p-adic
Lagrangians. The very attractive feature of this new Lagrangian is that it is
an analytic function of the d'Alembertian. Investigation of the field theory
with Riemann zeta function is interesting in itself as well.Comment: 10 pages. Presented at the 2nd Conf. on SFT and Related Topics,
Moscow, April 2009. Submitted to Theor. Math. Phy
Radiometric force in dusty plasmas
A radiofrequency glow discharge plasma, which is polluted with a certain
number of dusty grains, is studied. In addition to various dusty plasma
phenomena, several specific colloidal effects should be considered. We focus on
radiometric forces, which are caused by inhomogeneous temperature distribution.
Aside from thermophoresis, the role of temperature distribution in dusty
plasmas is an open question. It is shown that inhomogeneous heating of the
grain by ion flows results in a new photophoresis like force, which is specific
for dusty discharges. This radiometric force can be observable under conditions
of recent microgravity experiments.Comment: 4 pages, amsmat
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