2,490,466 research outputs found
Non-Resonant Effects in Implementation of Quantum Shor Algorithm
We simulate Shor's algorithm on an Ising spin quantum computer. The influence
of non-resonant effects is analyzed in detail. It is shown that our ``''-method successfully suppresses non-resonant effects even for relatively
large values of the Rabi frequency.Comment: 11 pages, 13 figure
Distinct turbulence saturation regimes in stellarators
In the complex 3D magnetic fields of stellarators, ion-temperature-gradient
turbulence is shown to have two distinct saturation regimes, as revealed by
petascale numerical simulations, and explained by a simple turbulence theory.
The first regime is marked by strong zonal flows, and matches previous
observations in tokamaks. The newly observed second regime, in contrast,
exhibits small- scale quasi-two-dimensional turbulence, negligible zonal flows,
and, surprisingly, a weaker heat flux scaling. Our findings suggest that key
details of the magnetic geometry control turbulence in stellarators.Comment: Erratum added to en
Asymptotic expansion of the solution of the steady Stokes equation with variable viscosity in a two-dimensional tube structure
The Stokes equation with the varying viscosity is considered in a thin tube
structure, i.e. in a connected union of thin rectangles with heights of order
and with bases of order 1 with smoothened boundary. An
asymptotic expansion of the solution is constructed: it contains some
Poiseuille type flows in the channels (rectangles) with some boundary layers
correctors in the neighborhoods of the bifurcations of the channels. The
estimates for the difference of the exact solution and its asymptotic
approximation are proved.Comment: 22 pages, 20 figure
Synchrotron and Compton Components and their Variability in BL Lac Objects
BL Lacertae objects are extreme extragalactic sources characterized by the
emission of strong and rapidly variable nonthermal radiation over the entire
electromagnetic spectrum. Synchrotron emission followed by inverse Compton
scattering in a relativistic beaming scenario is generally thought to be the
mechanism powering these objects. ...Comment: 4 pages, TeX plus 3 figures. Proceedings of the conference "X-ray
Astronomy 1999", September 6-10,1999, Bologn
Asymptotic behavior of Structures made of Plates
The aim of this work is to study the asymptotic behavior of a structure made
of plates of thickness when . This study is carried on
within the frame of linear elasticity by using the unfolding method. It is
based on several decompositions of the structure displacements and on the
passing to the limit in fixed domains. We begin with studying the displacements
of a plate. We show that any displacement is the sum of an elementary
displacement concerning the normal lines on the middle surface of the plate and
a residual displacement linked to these normal lines deformations. An
elementary displacement is linear with respect to the variable 3. It is
written where U is a displacement of the mid-surface of
the plate. We show a priori estimates and convergence results when . We characterize the limits of the unfolded displacements of a plate as well
as the limits of the unfolded of the strained tensor. Then we extend these
results to the structures made of plates. We show that any displacement of a
structure is the sum of an elementary displacement of each plate and of a
residual displacement. The elementary displacements of the structure (e.d.p.s.)
coincide with elementary rods displacements in the junctions. Any e.d.p.s. is
given by two functions belonging to where S is the skeleton of the
structure (the plates mid-surfaces set). One of these functions : U is the
skeleton displacement. We show that U is the sum of an extensional displacement
and of an inextensional one. The first one characterizes the membrane
displacements and the second one is a rigid displacement in the direction of
the plates and it characterizes the plates flexion. Eventually we pass to the
limit as in the linearized elasticity system, on the one hand we
obtain a variational problem that is satisfied by the limit extensional
displacement, and on the other hand, a variational problem satisfied by the
limit of inextensional displacements
Vortex-Bright Soliton Dipoles: Bifurcations, Symmetry Breaking and Soliton Tunneling in a Vortex-Induced Double Well
The emergence of vortex-bright soliton dipoles in two-component Bose-Einstein
condensates through bifurcations from suitable eigenstates of the underlying
linear system is examined. These dipoles can have their bright solitary
structures be in phase (symmetric) or out of phase (anti-symmetric). The
dynamical robustness of each of these two possibilities is considered and the
out-of-phase case is found to exhibit an intriguing symmetry-breaking
instability that can in turn lead to tunneling of the bright wavefunction
between the two vortex "wells". We interpret this phenomenon by virtue of a
vortex-induced double well system, whose spontaneous symmetry breaking leads to
asymmetric vortex-bright dipoles, in addition to the symmetric and
anti-symmetric ones. The theoretical prediction of these states is corroborated
by detailed numerical computations.Comment: 14 pages, 8 figure
On the ternary complex analysis and its applications
Previouly a possible extension of the complex number, together with its
connected trigonometry was introduced. In this paper we focuss on the simplest
case of ternary complex numbers. Then, some types of holomorphicity adapted to
the ternary complex numbers and the corresponding results upon integration of
differential forms are given. Several physical applications are given, and in
particuler one type of holomorphic function gives rise to a new form of
stationary magnetic field. The movement of a monopole type object in this field
is then studied and shown to be integrable. The monopole scattering in the
ternary field is finally studied.Comment: LaTeX 28 page
On prefilters for digital FIR filter design
A new family of digital prefilter structures is introduced, based on the Dolph-Chebyshev function. These prefilters can be combined with appropriately designed "equalizer" filters based on equiripple methods, leading to efficient FIR digital filter designs. Design examples are included, demonstrating the simplicity of the resulting designs, as compared to conventional equiripple designs
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