Ornstein-Zernike Theory for the finite range Ising models above T_c

We derive precise Ornstein-Zernike asymptotic formula for the decay of the two-point function in the general context of finite range Ising type models on Z^d. The proof relies in an essential way on the a-priori knowledge of the strict exponential decay of the two-point function and, by the sharp characterization of phase transition due to Aizenman, Barsky and Fernandez, goes through in the whole of the high temperature region T > T_c. As a byproduct we obtain that for every T > T_c, the inverse correlation length is an analytic and strictly convex function of direction.Comment: 36 pages, 5 figure

Random path representation and sharp correlations asymptotics at high-temperatures

We recently introduced a robust approach to the derivation of sharp asymptotic formula for correlation functions of statistical mechanics models in the high-temperature regime. We describe its application to the nonperturbative proof of Ornstein-Zernike asymptotics of 2-point functions for self-avoiding walks, Bernoulli percolation and ferromagnetic Ising models. We then extend the proof, in the Ising case, to arbitrary odd-odd correlation functions. We discuss the fluctuations of connection paths (invariance principle), and relate the variance of the limiting process to the geometry of the equidecay profiles. Finally, we explain the relation between these results from Statistical Mechanics and their counterparts in Quantum Field Theory

Winterbottom Construction for Finite Range Ferromagnetic Models: An L_1 Approach

We provide a rigorous microscopic derivation of the thermodynamic description of equilibrium crystal shapes in the presence of a substrate, first studied by Winterbottom. We consider finite range ferromagnetic Ising models with pair interactions in dimensions greater or equal to 3, and model the substrate by a finite-range boundary magnetic field acting on the spins close to the bottom wall of the box

Rigorous Non-Perturbative Ornstein-Zernike Theory for Ising Ferromagnets

We rigorously derive the Ornstein-Zernike asymptotics of the pair-correlation functions for finite-range Ising ferromagnets in any dimensions and at any temperature above critical

Non-penalization and Non-Criminalization

The Oxford Handbook of International Refugee Law is a comprehensive, critical work, which analyses the state of research across the refugee law regime as a whole. Drawing together leading and emerging scholars, the Handbook provides both doctrinal and theoretical analyses of international refugee law and practice. It critiques existing law from a variety of normative positions, with several chapters identifying foundational flaws that open up space for radical rethinking. The Handbook aspires to be global, both legally and geographically. Contributions assess a wide range of international legal instruments relevant to refugee protection, including from international human rights law, international humanitarian law, international migration law, the law of the sea, and international and transnational criminal law. Ultimately, the Handbook provides an account, as well as a critique, of the status quo, and in so doing it sets the agenda for future academic research in international refugee law

A Note on the Decay of Correlations Under δ\delta-Pinning

We prove that for a class of massless $\nabla\phi$ interface models on \Ztwo an introduction of an arbitrary small pinning self-potential leads to exponential decay of correlation, or, in other words, to creation of mass.Comment: 9 page

Article 31 of the 1951 Convention Relating to the Status of Refugees

The aim of this paper is to clarify the correct interpretation of Article 31 of the 1951 Convention Relating to the Status of Refugees (the 1951 Refugee Convention). The interpretation proposed is based on the binding international precepts relating to treaty interpretation, as reflected in Articles 31 to 33 of the Vienna Convention on the Law of Treaties (VCLT), as discussed in the next section. This paper draws on the contemporary practice around Article 31 by States parties to the 1951 Refugee Convention and/or its 1967 Protocol, clarifying where those interpretations are correct, and where State practice appears to depart from the obligations in Article 31. The aim of the paper is ultimately to inform UNHCR when developing guidelines on Article 31

Bi-local baryon interpolating fields with two flavours

We construct bi-local interpolating field operators for baryons consisting of three quarks with two flavors, assuming good isospin symmetry. We use the restrictions following from the Pauli principle to derive relations/identities among the baryon operators with identical quantum numbers. Such relations that follow from the combined spatial, Dirac, color, and isospin Fierz transformations may be called the (total/complete) Fierz identities. These relations reduce the number of independent baryon operators with any given spin and isospin. We also study the Abelian and non-Abelian chiral transformation properties of these fields and place them into baryon chiral multiplets. Thus we derive the independent baryon interpolating fields with given values of spin (Lorentz group representation), chiral symmetry ($U_L(2) \times U_R(2)$ group representation) and isospin appropriate for the first angular excited states of the nucleon.Comment: 15 pages, 4 tables, accepted by EPJ

Low temperature field-effect in crystalline organic material

Molecular organic materials offer the promise of novel electronic devices but also present challenges for understanding charge transport in narrow band systems. Low temperature studies elucidate fundamental transport processes. We report the lowest temperature field effect transport results on a crystalline oligomeric organic material, rubrene. We find field effect switching with on-off ratio up to 10^7 at temperatures down to 10 K. Gated transport shows a factor of ~10 suppression of the thermal activation energy in 10-50 K range and nearly temperature independent resistivity below 10 K.Comment: 5 pages, 4 figure

A new approach to axial coupling constants in the QCD sum rule

We derive new QCD sum rules for the axial coupling constants by considering two-point correlation functions of the axial-vector currents in a one nucleon state. The QCD sum rules tell us that the axial coupling constants are expressed by nucleon matrix elements of quark and gluon operators which are related to the sigma terms and the moments of parton distribution functions. The results for the iso-vector axial coupling constants and the 8th component of the SU(3) octet are in good agreement with experiment.Comment: 10 pages, 1 figure include