A superconductor with 4-fermion attraction perturbed by magnetic impurities

A superconductor with 4-fermion attraction, considered by Ma\'{c}kowiak and Tarasewicz is modified by adding to the Hamiltonian a long-range magnetic interaction $V$ between conduction fermions and localized distinguishable spin 1/2 magnetic impurities. $V$ has the form of a reduced s-d interaction. An upper and lower bound to the system's free energy density $f(H,\beta)$ is derived and the two bounds are shown to coalesce in the thermodynamic limit. The resulting mean-field equations for the gap $\Delta$ and a parameter $y$, characterizing the impurity subsystem are solved and the solution minimizing $f$ is found for various values of magnetic coupling constant $g$ and impurity concentration. The phase diagrams of the system are depicted with five distinct phases: the normal phase, unperturbed superconducting phase, perturbed superconducting phase with nonzero gap in the excitation spectrum, perturbed gapless superconducting phase and impurity phase with completely suppressed superconductivity.Comment: 21 pages, 3 figure

A strategy in sports betting with the nearest neighbours search and genetic algorithms

The point of sports betting is not merely to correctly predict the outcome of a game, but to actually win on a bet. We propose a model of sports betting that uses the nearest neighbours search and genetic algorithms to do the job. It uses data on the teams playing, their respective formations, individual players, results of previous games, as well as odds offered by bookmakers. The model has been trained using the data from the seasons 2002/03 until 2008/09 of the English Premier League and tested against the already played games of the seasons 2009/10 and 2010/11

Spór o korzenie nazizmu. Hannah Arendt i Erica Voegelina koncepcje źródeł zjawiska

Published in 1951, The origins of totalitarianism was a quantum leap in Hannah Arendt’s academic career. The book made her one of the most important scholars of Nazi ideology. Arendt’s work also won wide acclaim, partly due to a critical review by Eric Voegelin, which did not remain without responses from the author (both in public and in private correspondence). This paper tries to reconstruct the debates of Hannah Arendt and Eric Voegelin (including in the articles New science of politics and Some problems of German hegemony) on the origins of Nazism

Developing national level informatics competencies for undergraduate nurses : methodological approaches from Australia and Canada

Health information systems are being implemented in countries by governments and regional health authorities in an effort to modernize healthcare. With these changes, there has emerged a demand by healthcare organizations for nurses graduating from college and university programs to have acquired nursing informatics competencies that would allow them to work in clinical practice settings (e.g. hospitals, clinics, home care etc). In this paper we examine the methods employed by two different countries in developing national level nursing informatics competencies expected of undergraduate nurses prior to graduation (i.e. Australia, Canada). This work contributes to the literature by describing the science and methods of nursing informatics competency development at a national level

Regularization of the Particle-Particle Interaction in the Nuclear Density Functional Theory

In this work we show how to regularize the ultraviolet divergences appearing in the local pairing term of the energy density functional. Our approach, entirely rooted in the framework of the Density Functional Theory, is based on the regularization of local densities and currents and can be applied to various classes of energy density functionals. We demonstrated, that for the particular choice of the pairing term of energy density functional, our procedure gives the same regularization scheme to the one obtained earlier by the means of the pairing gap regularization. We also investigated the non-unitarity of the Bogoliubov tranformation due to the energy cutoff in the quasiparticle space. We developed and tested the method of restoring the unitarity of the Bogoliubov transformation. We demonstrated that by applying this method one can perform HFB calculations for significantly lower cutoff energies, without losing accuracy