Nonperturbative study of the two-frequency sine-Gordon model

The two-frequency sine-Gordon model is examined. The focus is mainly on the case when the ratio of the frequencies is 1/2, given the recent interest in the literature. We discuss the model both in a perturbative (form factor perturbation theory) and a nonperturbative (truncated conformal space approach) framework, and give particular attention to a phase transition conjectured earlier by Delfino and Mussardo. We give substantial evidence that the transition is of second order and that it is in the Ising universality class. Furthermore, we check the UV-IR operator correspondence and conjecture the phase diagram of the theory.Comment: Minor corrections, LaTeX2e, 39 pages, 26 figures (4 pslatex, 1 postscript and 21 eps

Living Labs and Partnerships for Progress: How Universities can Drive the Process towards the Sustainable City

Universities can play an active role in facilitating the deployment at a wide scale of the sustainability concept, strictly cooperating with public-private institutions and civil society. Following this path, the University of Genoa, Italy, decided to transform its Savona Campus into a Living Lab aimed at creating a model of a sustainable urban district, to be replicated at the city level with specific implementation projects. Different actions on sustainable energy, smart environment and social health & wellbeing have been deployed: energy efficiency interventions, smart grid connected to a zero-emission building, electrical mobility and outdoor sport activities. All the projects have been developed with the active involvement and the empowerment of the Campus community (students and faculty) and thanks to important collaborations with local public institutions and industrial companies. The main partnerships towards the achievements of sustainability goals are with the Italian Electricity company, Enel S.p.A. and with the Savona Municipality, which enabled the extension of the Smart City experimentation to Savona population. These projects are constantly promoted and disseminated to university students during lessons, to visiting schools and civil society during specific events on sustainability topics inside the city

Form factors in the Bullough-Dodd related models: The Ising model in a magnetic field

We consider particular modification of the free-field representation of the form factors in the Bullough-Dodd model. The two-particles minimal form factors are excluded from the construction. As a consequence, we obtain convenient representation for the multi-particle form factors, establish recurrence relations between them and study their properties. The proposed construction is used to obtain the free-field representation of the lightest particles form factors in the $\Phi_{1,2}$ perturbed minimal models. As a significant example we consider the Ising model in a magnetic field. We check that the results obtained in the framework of the proposed free-field representation are in agreement with the corresponding results obtained by solving the bootstrap equations.Comment: 20 pages; v2: some misprints, textual inaccuracies and references corrected; some references and remarks adde

Boundary form factors of the sinh-Gordon model with Dirichlet boundary conditions at the self-dual point

In this manuscript we present a detailed investigation of the form factors of boundary fields of the sinh-Gordon model with a particular type of Dirichlet boundary condition, corresponding to zero value of the sinh-Gordon field at the boundary, at the self-dual point. We follow for this the boundary form factor program recently proposed by Z. Bajnok, L. Palla and G. Takaks in hep-th/0603171, extending the analysis of the boundary sinh-Gordon model initiated there. The main result of the paper is a conjecture for the structure of all n-particle form factors of two particular boundary operators in terms of elementary symmetric polynomials in certain functions of the rapidity variables. In addition, form factors of boundary "descendant" fields have been constructedComment: 14 pages LaTex. Version to appear in J. Phys.

THE STATISTICAL ANALYSIS OF ACTIVE CONTROL EQUIVALENCE STUDIES

In experimental work, the notion of equivalence falls short of the idea of equality. Thus, the effects of two treatments, while not identical, may still be regarded as equivalent if their difference is negligible in a certain sense. This simple distinction raises not only technical difficulties, since of necessity it results in special statistical procedures, but also deeper conceptual issues, since one has to ask why two treatments should be equivalent but not equal, more specifically, whether their being merely equivalent has any bearing on the practical questions posed by the data. In this paper we present examples, drawn from agricultural experiments, to address the statistical analysis of studies intended to show equivalence of effects. We formalize two notions of equivalence in the context of a horticultural experiment conducted on witloof chicory plants, to compare the efficacy of two treatments to prevent root infection. We then extend the work to include the concept of multivariate equivalence for the specific case of two simultaneous endpoints, seed implantation and germination, as the key features to accept that two corn planters are equivalent. We address this type of equivalence via nominal a level adjustments for multiple endpoints. Finally, we discuss these approaches and suggest areas for further research. Among these, we entertain the broader concept of equivalent performance under a defined range of experimental conditions

Isospin Constraints on the Parametric Coupling Model for Nuclear Matter

We make use of isospin constraints to study the parametric coupling model and the properties of asymmetric nuclear matter. Besides the usual constraints for nuclear matter - effective nucleon mass and the incompressibility at saturation density - and the neutron star constraints - maximum mass and radius - we have studied the properties related with the symmetry energy. These properties have constrained to a small range the parameters of the model. We have applied our results to study the thermodynamic instabilities in the liquid-gas phase transition as well as the neutron star configurations.Comment: 11 pages, 10 figure

Integrable structures in LGTs near the deconfinement transition

In this contribution we review some recent results about the emergence of 2D integrable systems in 3D Lattice Gauge Theories near the deconfinement transition. We focus on some concrete examples involving the flux tube thickness, the ratio of k-string tensions and Polyakov loops correlators in various models.Comment: 8 pages, Poster contribution to the XXVII International Symposium on Lattice Field Theory, July 26-31, 2009, Peking University, Beijing, Chin

Long range correlations generated by phase separation. Exact results from field theory

We consider near-critical planar systems with boundary conditions inducing phase separation. While order parameter correlations decay exponentially in pure phases, we show by direct field theoretical derivation how phase separation generates long range correlations in the direction parallel to the interface, and determine their exact analytic form. The latter leads to specific contributions to the structure factor of the interface

Direct laser interference patterning for photocatalytically active self-cleaning surfaces

Laser surface structuring has long proven to be a suitable tool to produce surfaces that repel both water and bacteria on actively antibacterial and inert surfaces. As a mostly undesired side effect, the laser induced surface oxidation, that occurs when producing the pattern can also have a significant effect on the behavior of the surface. For this reason, the focus of this work is to employ direct laser interference patterning to not only affect the surface topography of titanium but to simultaneously produce a precisely tailored oxide layer. Using this approach, photocatalytically active surfaces were produced. Those surfaces can produce a variety of radicals when illuminated with UV-A light which are then used to degrade organic compounds like bacteria or organic waste. With this in mind, this work aims to develop a one-step production method for self-cleaning surfaces that uses not only the lasers topographical but also its chemical surface modifications to produce photocatalytically active surfaces with high surface area