20,777 research outputs found
Phase transitions in Ising model on a Euclidean network
A one dimensional network on which there are long range bonds at lattice
distances with the probability has been taken
under consideration. We investigate the critical behavior of the Ising model on
such a network where spins interact with these extra neighbours apart from
their nearest neighbours for . It is observed that there is
a finite temperature phase transition in the entire range. For , finite size scaling behaviour of various quantities are consistent with
mean field exponents while for , the exponents depend on
. The results are discussed in the context of earlier observations on
the topology of the underlying network.Comment: 7 pages, revtex4, 7 figures; to appear in Physical Review E, minor
changes mad
Instability of Shear Waves in an Inhomogeneous Strongly Coupled Dusty Plasma
It is demonstrated that low frequency shear modes in a strongly coupled,
inhomogeneous, dusty plasma can grow on account of an instability involving the
dynamical charge fluctuations of the dust grains. The instability is driven by
the gradient of the equilibrium dust charge density and is associated with the
finite charging time of the dust grains. The present calculations, carried out
in the generalized hydrodynamic viscoelastic formalism, also bring out
important modifications in the threshold and growth rate of the instability due
to collective effects associated with coupling to the compressional mode.Comment: 9 pages with 2 figure
Experimental study of nonlinear dust acoustic solitary waves in a dusty plasma
The excitation and propagation of finite amplitude low frequency solitary
waves are investigated in an Argon plasma impregnated with kaolin dust
particles. A nonlinear longitudinal dust acoustic solitary wave is excited by
pulse modulating the discharge voltage with a negative potential. It is found
that the velocity of the solitary wave increases and the width decreases with
the increase of the modulating voltage, but the product of the solitary wave
amplitude and the square of the width remains nearly constant. The experimental
findings are compared with analytic soliton solutions of a model Kortweg-de
Vries equation.Comment: The manuscripts includes six figure
Remark about Non-BPS D-Brane in Type IIA Theory
In this paper we would like to show simple mechanisms how from the action for
non-BPS D-brane we can obtain action describing BPS D(p-1)-brane in Type IIA
theory.Comment: 13 pages, completely rewritten pape
A wave driver theory for vortical waves propagating across junctions with application to those between rigid and compliant walls
A theory is described for propagation of vortical waves across alternate rigid and compliant panels. The structure in the fluid side at the junction of panels is a highly vortical narrow viscous structure which is idealized as a wave driver. The wave driver is modelled as a ‘half source cum half sink’. The incoming wave terminates into this structure and the outgoing wave emanates from it. The model is described by half Fourier–Laplace transforms respectively for the upstream and downstream sides of the junction. The cases below cutoff and above cutoff frequencies are studied. The theory completely reproduces the direct numerical simulation results of Davies & Carpenter (J. Fluid Mech., vol. 335, 1997, p. 361). Particularly, the jumps across the junction in the kinetic energy integral, the vorticity integral and other related quantities as obtained in the work of Davies & Carpenter are completely reproduced. Also, some important new concepts emerge, notable amongst which is the concept of the pseudo group velocity
Emerging trends in the design of pollution control system for metallurgical industries
The paper discusses the emerging trends in the design of pollution control systems for both air as well as water pollution. Recent trends in the design of high efficiency cyclones have been touched upon. In the area of water pollution,the application of bio-technology for mitigation of water pollution have been .stressed
Hidden Translation and Translating Coset in Quantum Computing
We give efficient quantum algorithms for the problems of Hidden Translation
and Hidden Subgroup in a large class of non-abelian solvable groups including
solvable groups of constant exponent and of constant length derived series. Our
algorithms are recursive. For the base case, we solve efficiently Hidden
Translation in , whenever is a fixed prime. For the induction
step, we introduce the problem Translating Coset generalizing both Hidden
Translation and Hidden Subgroup, and prove a powerful self-reducibility result:
Translating Coset in a finite solvable group is reducible to instances of
Translating Coset in and , for appropriate normal subgroups of
. Our self-reducibility framework combined with Kuperberg's subexponential
quantum algorithm for solving Hidden Translation in any abelian group, leads to
subexponential quantum algorithms for Hidden Translation and Hidden Subgroup in
any solvable group.Comment: Journal version: change of title and several minor update
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