1,688 research outputs found
From finite geometry exact quantities to (elliptic) scattering amplitudes for spin chains: the 1/2-XYZ
Initially, we derive a nonlinear integral equation for the vacuum counting
function of the spin 1/2-XYZ chain in the {\it disordered regime}, thus
paralleling similar results by Kl\"umper \cite{KLU}, achieved through a
different technique in the {\it antiferroelectric regime}. In terms of the
counting function we obtain the usual physical quantities, like the energy and
the transfer matrix (eigenvalues). Then, we introduce a double scaling limit
which appears to describe the sine-Gordon theory on cylindrical geometry, so
generalising famous results in the plane by Luther \cite{LUT} and Johnson et
al. \cite{JKM}. Furthermore, after extending the nonlinear integral equation to
excitations, we derive scattering amplitudes involving solitons/antisolitons
first, and bound states later. The latter case comes out as manifestly related
to the Deformed Virasoro Algebra of Shiraishi et al. \cite{SKAO}. Although this
nonlinear integral equations framework was contrived to deal with finite
geometries, we prove it to be effective for discovering or rediscovering
S-matrices. As a particular example, we prove that this unique model furnishes
explicitly two S-matrices, proposed respectively by Zamolodchikov \cite{ZAMe}
and Lukyanov-Mussardo-Penati \cite{LUK, MP} as plausible scattering description
of unknown integrable field theories.Comment: Article, 41 pages, Late
The dilute A model, the E mass spectrum and the tricritical Ising model
The exact perturbation approach is used to derive the (seven) elementary
correlation lengths and related mass gaps of the two-dimensional dilute A
lattice model in regime 2- from the Bethe ansatz solution. This model provides
a realisation of the integrable perturbation of the c=7/10
conformal field theory, which is known to describe the off-critical thermal
behaviour of the tricritical Ising model. The E masses predicted from
purely elastic scattering theory follow in the approach to criticality.
Universal amplitudes for the tricritical Ising model are calculated.Comment: 24 pages, LaTeX, submitted to Journal of Mathematical Physics. One
paragraph added and some minor typos correcte
The generalised scaling function: a systematic study
We describe a procedure for determining the generalised scaling functions
at all the values of the coupling constant. These functions describe
the high spin contribution to the anomalous dimension of large twist operators
(in the sector) of SYM. At fixed , can be
obtained by solving a linear integral equation (or, equivalently, a linear
system with an infinite number of equations), whose inhomogeneous term only
depends on the solutions at smaller . In other words, the solution can be
written in a recursive form and then explicitly worked out in the strong
coupling regime. In this regime, we also emphasise the peculiar convergence of
different quantities ('masses', related to the ) to the unique mass gap
of the nonlinear sigma model and analyse the first next-to-leading order
corrections.Comment: Latex version, journal version (with explanatory appendices and more
references
Universal structure of subleading infrared poles at strong coupling
Recently a concise expression for the subleading infrared singularity of
dimensional-regularized gauge theories has been proposed. For conformal
theories, such relation involves a universal eikonal contribution plus a
non-eikonal contribution, related to the subleading term in the anomalous
dimension of twist two operators with large spin. In this note we make use of
the AdS/CFT correspondence in order to check such conjecture at strong coupling
for the case of N=4 SYM.Comment: 13 page
Extended Y-system for the correspondence
We study the analytic properties of the Y functions. It is
shown that the TBA equations, including the dressing factor, can be obtained
from the Y-system with some additional information on the square-root
discontinuities across semi-infinite segments in the complex plane. The
Y-system extended by the discontinuity relations constitutes a fundamental set
of local functional constraints that can be easily transformed into integral
form through Cauchy's theorem.Comment: LaTeX2e, 42 pages, 7 figures. v2: 45 pages, references and a new
appendix included, typos corrected. v3: minor typos corrected, references
adde
Three realizations of quantum affine algebra
In this article we establish explicit isomorphisms between three realizations
of quantum twisted affine algebra : the Drinfeld ("current")
realization, the Chevalley realization and the so-called realization,
investigated by Faddeev, Reshetikhin and Takhtajan.Comment: 15 page
Circulating levels of the adipocytokines vaspin and omentin in patients with Kawasaki disease
Quantum folded string and integrability: from finite size effects to Konishi dimension
Using the algebraic curve approach we one-loop quantize the folded string
solution for the type IIB superstring in AdS(5)xS(5). We obtain an explicit
result valid for arbitrary values of its Lorentz spin S and R-charge J in terms
of integrals of elliptic functions. Then we consider the limit S ~ J ~ 1 and
derive the leading three coefficients of strong coupling expansion of short
operators. Notably, our result evaluated for the anomalous dimension of the
Konishi state gives 2\lambda^{1/4}-4+2/\lambda^{1/4}. This reproduces correctly
the values predicted numerically in arXiv:0906.4240. Furthermore we compare our
result using some new numerical data from the Y-system for another similar
state. We also revisited some of the large S computations using our methods. In
particular, we derive finite--size corrections to the anomalous dimension of
operators with small J in this limit.Comment: 20 pages, 1 figure; v2: references added, typos corrected; v3: major
improvement of the references; v4: Discussion of short operators is
restricted to the case n=1. This restriction does not affect the main results
of the pape
Serum amyloid A circulating levels and disease activity in patients with juvenile idiopathic arthritis
Helminth infection of the loggerhead sea turtle caretta caretta along the coasts of sicily and the north west adriatic sea
We provide new data on the presence of helminth parasites in 64 individual loggerhead sea turtles Caretta caretta stranded along the coasts of Sicily and the northwest Adriatic Sea between June 2014 and August 2016. The necropsy examination revealed 31 individuals (48.4%) positive for endoparasites, showing a greater prevalence of trematodes than nematodes. In particular, seven species and a single genus of Trematoda (Hapalotrema) and a single species and genus of Nematoda (Kathlania) were identified. Among the Digenea flukes the species with the highest prevalence of infection were Rhytidodes gelatinosus (34.6%) and Hapalotrema sp. (33.3%), while among the Nematoda they were Kathlania sp. (33.3%) and Sulcascaris sulcata (33.3%). Analysis of variance (ANOVA) was applied among the recovery sites of the stranded loggerhead sea turtles and prevalence of endoparasites was used to highlight any relationship between the parasites and the origin of the hosts. ANOVA showed significant differences (p < 0.001) among the data used
- …