51,581 research outputs found
Some Exact Solutions for Maximally Symmetric Topological Defects in Anti de Sitter Space
We obtain exact analytical solutions for a class of SO() Higgs field
theories in a non-dynamic background -dimensional anti de Sitter space.
These finite transverse energy solutions are maximally symmetric
-dimensional topological defects where . The radius of curvature
of anti de Sitter space provides an extra length scale that allows us to study
the equations of motion in a limit where the masses of the Higgs field and the
massive vector bosons are both vanishing. We call this the double BPS limit. In
anti de Sitter space, the equations of motion depend on both and . The
exact analytical solutions are expressed in terms of standard special
functions. The known exact analytical solutions are for kink-like defects
(), vortex-like defects (), and the
'tHooft-Polyakov monopole (). A bonus is that the double BPS limit
automatically gives a maximally symmetric classical glueball type solution. In
certain cases where we did not find an analytic solution, we present numerical
solutions to the equations of motion. The asymptotically exponentially
increasing volume with distance of anti de Sitter space imposes different
constraints than those found in the study of defects in Minkowski space.Comment: 45 pages, 19 figures. In version 2: added two paragraphs about how
our double BPS limit automatically gives a solution to the Yang-Mills
equation, and related it to Yang-Mills solutions in AdS_4 that appeared on
the same day in eprint 1708.0636
On asymptotic behavior of work distributions for driven Brownian motion
We propose a simple conjecture for the functional form of the asymptotic
behavior of work distributions for driven overdamped Brownian motion of a
particle in confining potentials. This conjecture is motivated by the fact that
these functional forms are independent of the velocity of the driving for all
potentials and protocols, where explicit analytical solutions for the work
distributions have been derived in the literature. To test the conjecture, we
use Brownian dynamics simulations and a recent theory developed by Engel and
Nickelsen (EN theory), which is based on the contraction principle of large
deviation theory. Our tests suggest that the conjecture is valid for potentials
with a confinement equal to or weaker than the parabolic one, both for
equilibrium and for nonequilibrium distributions of the initial particle
position. In addition we obtain a new analytical solution for the asymptotic
behavior of the work distribution for the V-potential by application of the EN
theory, and we extend this theory to nonequilibrated initial particle
positions
Antiperiodic XXZ chains with arbitrary spins: Complete eigenstate construction by functional equations in separation of variables
Generic inhomogeneous integrable XXZ chains with arbitrary spins are studied
by means of the quantum separation of variables (SOV) method. Within this
framework, a complete description of the spectrum (eigenvalues and eigenstates)
of the antiperiodic transfer matrix is derived in terms of discrete systems of
equations involving the inhomogeneity parameters of the model. We show here
that one can reformulate this discrete SOV characterization of the spectrum in
terms of functional T-Q equations of Baxter's type, hence proving the
completeness of the solutions to the associated systems of Bethe-type
equations. More precisely, we consider here two such reformulations. The first
one is given in terms of Q-solutions, in the form of trigonometric polynomials
of a given degree , of a one-parameter family of T-Q functional equations
with an extra inhomogeneous term. The second one is given in terms of
Q-solutions, again in the form of trigonometric polynomials of degree but
with double period, of Baxter's usual (i.e. without extra term) T-Q functional
equation. In both cases, we prove the precise equivalence of the discrete SOV
characterization of the transfer matrix spectrum with the characterization
following from the consideration of the particular class of Q-solutions of the
functional T-Q equation: to each transfer matrix eigenvalue corresponds exactly
one such Q-solution and vice versa, and this Q-solution can be used to
construct the corresponding eigenstate.Comment: 38 page
Surface properties of fluids of charged platelike colloids
Surface properties of mixtures of charged platelike colloids and salt in
contact with a charged planar wall are studied within density functional
theory. The particles are modeled by hard cuboids with their edges constrained
to be parallel to the Cartesian axes corresponding to the Zwanzig model and the
charges of the particles are concentrated in their centers. The density
functional applied is an extension of a recently introduced functional for
charged platelike colloids. Analytically and numerically calculated bulk and
surface phase diagrams exhibit first-order wetting for sufficiently small
macroion charges and isotropic bulk order as well as first-order drying for
sufficiently large macroion charges and nematic bulk order. The asymptotic
wetting and drying behavior is investigated by means of effective interface
potentials which turn out to be asymptotically the same as for a suitable
neutral system governed by isotropic nonretarded dispersion forces. Wetting and
drying points as well as predrying lines and the corresponding critical points
have been located numerically. A crossover from monotonic to non-monotonic
electrostatic potential profiles upon varying the surface charge density has
been observed. Due to the presence of both the Coulomb interactions and the
hard-core repulsions, the surface potential and the surface charge do not
vanish simultaneously, i.e., the point of zero charge and the isoelectric point
of the surface do not coincide.Comment: 14 pages, submitte
Quantitative Properties on the Steady States to A Schr\"odinger-Poisson-Slater System
A relatively complete picture on the steady states of the following
Schrdinger-Poisson-Slater (SPS) system \begin{cases} -\Delta
Q+Q=VQ-C_{S}Q^{2}, & Q>0\text{ in }\mathbb{R}^{3}\\ Q(x)\to0, & \mbox{as
}x\to\infty,\\ -\Delta V=Q^{2}, & \text{in }\mathbb{R}^{3}\\ V(x)\to0 &
\mbox{as }x\to\infty. \end{cases}
is given in this paper: existence, uniqueness, regularity and asymptotic
behavior at infinity, where is a constant. To the author's knowledge,
this is the first uniqueness result on SPS system
Acausality in Gowdy spacetimes
We present a parametrization of and Gowdy cosmological
models which allows us to study both types of topologies simultaneously. We
show that there exists a coordinate system in which the general solution of the
linear polarized special case (with both topologies) has exactly the same
functional dependence. This unified parametrization is used to investigate the
existence of Cauchy horizons at the cosmological singularities, leading to a
violation of the strong cosmic censorship conjecture. Our results indicate that
the only acausal spacetimes are described by the Kantowski-Sachs and the
Kerr-Gowdy metrics.Comment: Typos corrected, 10 pages. Dedicated to Michael P. Ryan on the
occasion of his 60-th birthda
On the Thermodynamic Bethe Ansatz Equation in Sinh-Gordon Model
Two implicit periodic structures in the solution of sinh-Gordon thermodynamic
Bethe ansatz equation are considered. The analytic structure of the solution as
a function of complex is studied to some extent both analytically and
numerically. The results make a hint how the CFT integrable structures can be
relevant in the sinh-Gordon and staircase models. More motivations are figured
out for subsequent studies of the massless sinh-Gordon (i.e. Liouville) TBA
equation.Comment: 32 pages, 18 figures, myart.st
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