Efimov Effect Revisited with Inclusion of Distortions

An elementary proof of the 3-body Efimov effect is provided in the case of a separable 2-body potential which binds at zero energy a light particle to a heavy one. The proof proceeds by two steps, namely {\it i)} a projection of the Hamiltonian in a subspace and the observation that the projected Hamiltonian generates an arbitrarily large number of bound states, and {\it ii)} a use of the Hylleraas-Undheim theorem to recover the unprojected Hamiltonian. The definition of the projectors we use can include mean field distortions.Comment: 17 pages, TeX Email contact= [email protected]

How researches are done in the law field? : reflections from the study of monographs of law courses in Brazil

In order to understand the impact of new technologies on the law through the science of law, it is essential to observe how Law researches are done. This paper pursues the following models of legal science: analytical (theory of formal rule); hermeneutics (interpretation theory) and empirical (decision theory) to appraise methodological procedures used in monograph researches in some Brazilian Law courses. This study was to detect which model of law science was used in the development of Law researches. The study was conducted, through Juris Doctors’ interviews. All of these respondents have written a monograph, which is a requirement to complete a Law course in Brazil. The main conclusions of this study were the following: 1) most of the monographs produced do not specify the methodology used for developing the work; 2) when the papers indicate the methodology used, the analytical model was prevalent. In these cases, the science of law appears as a systematization of rules for obtaining possible decisions. 3) Hermeneutic and empirical models were also used, but on a smaller scale. These researches revealed the inaccuracy of the methodological tools used to apprehend the reality. However, these strategies are significant to define the objects of study of law in the contemporary time. Answering the question about how Law researches are done in some Brazilian Law schools, this paper discusses the construction of classical models of science of law, which were taken as the theoretical framework of this work before the hypercomplex current problems

Applying a Life-Cycle Costs Approach to Water

This working paper presents findings and recommendations from the application of a life-cycle costs approach (LCCA) to water supply services in rural communities and small towns1 in four countries -- Andhra Pradesh (India), Burkina Faso, Ghana and Mozambique

Piecewise constant reconstruction of damaged color images

A variational model for reconstruction of damaged color images is studied, in particular in the case where only finitely many colors are admissible for the reconstructed image. An existence result and regularity properties of minimizers are presented