880,770 research outputs found
Graphical Representations for Ising and Potts Models in General External Fields
This work is concerned with the theory of Graphical Representation for the
Ising and Potts Models over general lattices with non-translation invariant
external field. We explicitly describe in terms of the Random Cluster
Representation the distribution function and, consequently, the expected value
of a single spin for the Ising and -states Potts Models with general
external fields. We also consider the Gibbs States for the Edwards-Sokal
Representation of the Potts Model with non-translation invariant magnetic field
and prove a version of the FKG Inequality for the so called General Random
Cluster Model (GRC Model) with free and wired boundary conditions in the
non-translation invariant case.
Adding the amenability hypothesis on the lattice, we obtain the uniqueness of
the infinite connected component and the quasilocality of the Gibbs Measures
for the GRC Model with such general magnetic fields. As a final application of
the theory developed, we show the uniqueness of the Gibbs Measures for the
Ferromagnetic Ising Model with a positive power law decay magnetic field, as
conjectured in [8].Comment: 56 pages. Accepted for publication in Journal of Statistical Physic
Central aspects of skew translation quadrangles, I
Except for the Hermitian buildings , up to a combination
of duality, translation duality or Payne integration, every known finite
building of type satisfies a set of general synthetic
properties, usually put together in the term "skew translation generalized
quadrangle" (STGQ). In this series of papers, we classify finite skew
translation generalized quadrangles. In the first installment of the series, as
corollaries of the machinery we develop in the present paper, (a) we obtain the
surprising result that any skew translation quadrangle of odd order is
a symplectic quadrangle; (b) we determine all skew translation quadrangles with
distinct elation groups (a problem posed by Payne in a less general setting);
(c) we develop a structure theory for root-elations of skew translation
quadrangles which will also be used in further parts, and which essentially
tells us that a very general class of skew translation quadrangles admits the
theoretical maximal number of root-elations for each member, and hence all
members are "central" (the main property needed to control STGQs, as which will
be shown throughout); (d) we solve the Main Parameter Conjecture for a class of
STGQs containing the class of the previous item, and which conjecturally
coincides with the class of all STGQs.Comment: 66 pages; submitted (December 2013
How to spice up a breakfast cereal or The translation of culturally bound referential items in âThe bluest eyeâ by Toni Morrison and âVinelandâ by Thomas Pynchon
This article will attempt to suggest translation procedures necessary to translate culturally bound items in the referential level of a literary work illustrated with examples from two novels: âThe Bluest Eyeâ by Toni Morrison and âVinelandâ by Thomas Pynchon. First, the article will include a general description of the referential level in literary works offering possible avenues of 285 its rendition, then and finally suggest a translation methodology and techniques together with practical examples of the theory at work
Magnetic translation groups in an n-dimensional torus
A charged particle in a uniform magnetic field in a two-dimensional torus has
a discrete noncommutative translation symmetry instead of a continuous
commutative translation symmetry. We study topology and symmetry of a particle
in a magnetic field in a torus of arbitrary dimensions. The magnetic
translation group (MTG) is defined as a group of translations that leave the
gauge field invariant. We show that the MTG on an n-dimensional torus is
isomorphic to a central extension of a cyclic group Z_{nu_1} x ... x
Z_{nu_{2l}} x T^m by U(1) with 2l+m=n. We construct and classify irreducible
unitary representations of the MTG on a three-torus and apply the
representation theory to three examples. We shortly describe a representation
theory for a general n-torus. The MTG on an n-torus can be regarded as a
generalization of the so-called noncommutative torus.Comment: 29 pages, LaTeX2e, title changed, re-organized, to be published in
Journal of Mathematical Physic
Remarks on some new models of interacting quantum fields with indefinite metric
We study quantum field models in indefinite metric. We introduce the modified
Wightman axioms of Morchio and Strocchi as a general framework of indefinite
metric quantum field theory (QFT) and present concrete interacting relativistic
models obtained by analytical continuation from some stochastic processes with
Euclidean invariance. As a first step towards scattering theory in indefinite
metric QFT, we give a proof of the spectral condition on the translation group
for the relativistic models.Comment: 13 page
Teleparallel Equivalent of Non-Abelian Kaluza-Klein Theory
Based on the equivalence between a gauge theory for the translation group and
general relativity, a teleparallel version of the non-abelian Kaluza-Klein
theory is constructed. In this theory, only the fiber-space turns out to be
higher-dimensional, spacetime being kept always four-dimensional. The resulting
model is a gauge theory that unifies, in the Kaluza-Klein sense, gravitational
and gauge fields. In contrast to the ordinary Kaluza-Klein models, this theory
defines a natural length-scale for the compact sub-manifold of the fiber space,
which is shown to be of the order of the Planck length.Comment: Revtex4, 7 pages, no figures, to appear in Phys. Rev.
Dualities in CHL-Models
We define a very general class of CHL-models associated with any string
theory (bosonic or supersymmetric) compactified on an internal CFT C x T^d. We
take the orbifold by a pair (g,\delta), where g is a (possibly non-geometric)
symmetry of C and \delta is a translation along T^d. We analyze the T-dualities
of these models and show that in general they contain Atkin-Lehner type
symmetries. This generalizes our previous work on N=4 CHL-models based on
heterotic string theory on T^6 or type II on K3 x T^2, as well as the
`monstrous' CHL-models based on a compactification of heterotic string theory
on the Frenkel-Lepowsky-Meurman CFT V^{\natural}.Comment: 18 page
Ward Identities for Transport in 2+1 Dimensions
We use the Ward identities corresponding to general linear transformations,
and derive relations between transport coefficients of -dimensional
systems. Our analysis includes relativistic and Galilean invariant systems, as
well as systems without boost invariance such as Lifshitz theories. We consider
translation invariant, as well as broken translation invariant cases, and
include an external magnetic field. Our results agree with effective theory
relations of incompressible Hall fluid, and with holographic calculations in a
magnetically charged black hole background.Comment: 17 pages, references and conclusions added. Published versio
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