1,304 research outputs found
Quasi-particle spectrum and entanglement generation after a quench in the quantum Potts spin chain
Recently, a non-trivial relation between the quasi-particle spectrum and
entanglement entropy production was discovered in non-integrable quenches in
the paramagnetic Ising quantum spin chain. Here we study the dynamics of
analogous quenches in the quantum Potts spin chain. Tuning the parameters of
the system, we observe a sudden increase in the entanglement production rate,
which is shown to be related to the appearance of new quasiparticle excitations
in the post-quench spectrum. Our results demonstrate the generality of the
effect and support its interpretation as the non-equilibrium version of the
well-known Gibbs paradox related to mixing entropy which appears in systems
with a non-trivial quasi-particle spectrum.Comment: 15 pages, pdflatex, 30 pdf figures. v2: reformatted, 22 pages, typos
correcte
A2 Toda theory in reduced WZNW framework and the representations of the W algebra
Using the reduced WZNW formulation we analyse the classical orbit content
of the space of classical solutions of the Toda theory. We define the
quantized Toda field as a periodic primary field of the algebra satisfying
the quantized equations of motion. We show that this local operator can be
constructed consistently only in a Hilbert space consisting of the
representations corresponding to the minimal models of the algebra.Comment: 38 page
Manual for obscuration code with space station applications
The Obscuration Code, referred to as SHADOW, is a user-oriented computer code to determine the case shadow of an antenna in a complex environment onto the far zone sphere. The surrounding structure can be composed of multiple composite cone frustums and multiply sided flat plates. These structural pieces are ideal for modeling space station configurations. The means of describing the geometry input is compatible with the NEC-BASIC Scattering Code. In addition, an interactive mode of operation has been provided for DEC VAX computers. The first part of this document is a user's manual designed to give a description of the method used to obtain the shadow map, to provide an overall view of the operation of the computer code, to instruct a user in how to model structures, and to give examples of inputs and outputs. The second part is a code manual that details how to set up the interactive and non-interactive modes of the code and provides a listing and brief description of each of the subroutines
Finite volume form factors in the presence of integrable defects
We developed the theory of finite volume form factors in the presence of
integrable defects. These finite volume form factors are expressed in terms of
the infinite volume form factors and the finite volume density of states and
incorporate all polynomial corrections in the inverse of the volume. We tested
our results, in the defect Lee-Yang model, against numerical data obtained by
truncated conformal space approach (TCSA), which we improved by renormalization
group methods adopted to the defect case. To perform these checks we determined
the infinite volume defect form factors in the Lee-Yang model exactly,
including their vacuum expectation values. We used these data to calculate the
two point functions, which we compared, at short distance, to defect CFT. We
also derived explicit expressions for the exact finite volume one point
functions, which we checked numerically. In all of these comparisons excellent
agreement was found.Comment: pdflatex, 34 pages, many figure
SUSY sine-Gordon theory as a perturbed conformal field theory and finite size effects
We consider SUSY sine-Gordon theory in the framework of perturbed conformal field theory. Using an argument from Zamolodchikov, we obtain the vacuum structure and the kink adjacency diagram of the theory, which is cross-checked against the exact S-matrix prediction, first-order perturbed conformal field theory (PCFT), the NLIE method and truncated conformal space approach. We provide evidence for consistency between the usual Lagrangian description and PCFT on the one hand, and between PCFT, NLIE and a massgap formula conjectured by Baseilhac and Fateev, on the other. In addition, we extend the NLIE description to all the vacua of the theory. (C) 2003 Elsevier B.V. All rights reserved
Exact Maximal Height Distribution of Fluctuating Interfaces
We present an exact solution for the distribution P(h_m,L) of the maximal
height h_m (measured with respect to the average spatial height) in the steady
state of a fluctuating Edwards-Wilkinson interface in a one dimensional system
of size L with both periodic and free boundary conditions. For the periodic
case, we show that P(h_m,L)=L^{-1/2}f(h_m L^{-1/2}) for all L where the
function f(x) is the Airy distribution function that describes the probability
density of the area under a Brownian excursion over a unit interval. For the
free boundary case, the same scaling holds but the scaling function is
different from that of the periodic case. Numerical simulations are in
excellent agreement with our analytical results. Our results provide an exactly
solvable case for the distribution of extremum of a set of strongly correlated
random variables.Comment: 4 pages revtex (two-column), 1 .eps figure include
Recommended from our members
Isotopic and genetic methods reveal the role of the gut microbiome in mammalian host essential amino acid metabolism.
Intestinal microbiota perform many functions for their host, but among the most important is their role in metabolism, especially the conversion of recalcitrant biomass that the host is unable to digest into bioavailable compounds. Most studies have focused on the assistance gut microbiota provide in the metabolism of carbohydrates, however, their role in host amino acid metabolism is poorly understood. We conducted an experiment on Mus musculus using 16S rRNA gene sequencing and carbon isotope analysis of essential amino acids (AAESS) to quantify the community composition of gut microbiota and the contribution of carbohydrate carbon used by the gut microbiome to synthesize AAESS that are assimilated by mice to build skeletal muscle tissue. The relative abundances of Firmicutes and Bacteroidetes inversely varied as a function of dietary macromolecular content, with Firmicutes dominating when mice were fed low-protein diets that contained the highest proportions of simple carbohydrates (sucrose). Mixing models estimated that the microbial contribution of AAESS to mouse muscle varied from less than 5% (threonine, lysine, and phenylalanine) to approximately 60% (valine) across diet treatments, with the Firmicute-dominated microbiome associated with the greatest contribution. Our results show that intestinal microbes can provide a significant source of the AAESS their host uses to synthesize structural tissues. The role that gut microbiota play in the amino acid metabolism of animals that consume protein-deficient diets is likely a significant but under-recognized aspect of foraging ecology and physiology
Boundary sine-Gordon model
We review our recent results on the on-shell description of sine-Gordon model
with integrable boundary conditions. We determined the spectrum of boundary
states together with their reflection factors by closing the boundary bootstrap
and checked these results against WKB quantization and numerical finite volume
spectra obtained from the truncated conformal space approach. The relation
between a boundary resonance state and the semiclassical instability of a
static classical solution is analyzed in detail.Comment: 15 pages, 7 eps figures, Talk presented at 'Workshop on Integrable
Theories, Solitons and Duality', 1-6 July 2002, Sao Paulo, Brazi
- …