An analysis of a regular black hole interior model

We analyze the thermodynamical properties of the regular static and spherically symmetric black hole interior model presented by Mboyne and Kazanas. Equations for the thermodynamical quantities valid for an arbitrary density profile are deduced, and from them we show that the model is thermodynamically unstable. Evidence is also presented pointing to its dynamical instability. The gravitational entropy of this solution based on the Weyl curvature conjecture is calculated, following the recipe given by Rudjord, Gr$\varnothing$n and Sigbj$\varnothing$rn, and it is shown to have the expected behavior.Comment: 22 pages, 17 figures, accepted for publication in International Journal of Theoretical Physic

Chicago, Keynes and Fiscal Policy

During the first half of the 1930’s, the founders of the Chicago School of economics and John Maynard Keynes in England advocated public works and as a cure for unemployment and a way to overcome the Great Depression. Counter cyclical fiscal policy was seen as a feasible strategy to attenuate the phases of the economic cycle. The quantity theory of money coupled with the hypothesis of wage and price rigidity provided the theoretical underpinnings for this policy proposal. These economists argued that a monetary policy channeled through the banking system was ineffective. In particular, Chicago economists identified two key features that exemplified this restriction: the instability of the circulation velocity of money and the fragility and underdevelopment of the banking system and financial structure. Fiscal policy was thus advocated on the basis of market rigidities and the impotency of monetary policy. By the end of the decade both Chicago economists and Keynes had departed from this fiscal policy stance. The former became concerned with the inflationar

Estudio de redes y etnografía en un grupo de trabajadores informales de la Plaza Foch

The investigation process and recollection of data is based on an ethnographic method. The investigation is focused in a group of informal car vigilants who work in the streets of the Plaza Foch sector. The investigator has built a utility function based on the data recollected with an observation method and the interaction with the group of interest.Mediante el proceso de investigación etnográfico se estudió el funcionamiento económico de un grupo de acomodadores de carros del sector La Mariscal Foch. El estudio se enfoca desde un punto de vista microeconómico. Se logra construir una función de utilidad por medio de la observación y la interacción con el espacio que ocupan los acomodadore

An analysis of a regular black hole interior model

We analyze the thermodynamical properties of the regular static and spherically symmetric black hole interior model presented by Mbonye and Kazanas. Equations for the thermodynamical quantities valid for an arbitrary density profile are deduced, and from them we show that the model is thermodynamically unstable. Evidence is also presented pointing to its dynamical instability. The gravitational entropy of this solution based on the Weyl curvature conjecture is calculated, following the recipe given by Rudjord, Grøn and Sigbjørn, and it is shown to have the expected behavior.Facultad de Ciencias Astronómicas y Geofísica

Anapole moment of the lightest neutralino in the cMSSM

We study the anapole moment of the lightest neutralino in the constrained Minimal Supersymmetric Standard Model (cMSSM). The electromagnetic anapole is the only allowed electromagnetic form factor for Majorana fermions, such as the neutralino. Since the neutralino is the LSP in many versions of the MSSM and therefore a candidate for dark matter, its characterization through its electromagnetic properties is important both for particle physics and for cosmology. We perform a scan in the parameter space of the cMSSM and find that the anapole moment is different from zero albeit very small ($< 10^{-3}$ GeV$^{-2}$). Combined with experimental constraints like the Higgs mass and the DM relic density, the allowed region of parameter space lies within the reach of future direct DM searches. Thus, the anapole moment could be used as a complementary constraint when studying the parameter space of the cMSSM and other similar models.Comment: 22 pages, 13 figures. arXiv admin note: substantial text overlap with arXiv:1206.505

Studying radioactivity through press news: the case of the Russian spy poisoning

Los medios de comunicación constituyen una importante vía de divulgación científica. Pero es posible ir más allá, ya que mediante una estrategia apropiada ciertas noticias pueden convertirse en una herramienta didáctica para la educación formal de ciencias. En este sentido, se han seleccionado algunas notas de prensa que conllevan una importante carga de contenidos científicos relativos a la radiactividad, si bien hacen referencia a un hecho que se encuadra dentro de la crónica de sucesos. El objetivo es discutir algunas pautas metodológicas para emplear esas noticias en el aula de ciencias a fin de reforzar el estudio de una serie de conceptos y términos relativos al fenómeno de la radiactividad y hacer su aprendizaje más ameno y atractivo para los alumnos.Media constitute an important way for scientific popularization. Nevertheless it is possible to go further, since some news can become an effective teaching aid in formal education of sciences by means of an adequate didactic strategy. In this sense, some pieces of news have been gathered due to their relation to scientific contents in the field of radioactivity, although the incident they referred to belongs to the section of accident and crime reports. The objective is to discuss some methodological guidelines to use that news in science classroom with the aim of reinforcing the study of important concepts and terms about the phenomenon of radioactivity, so that learning could become more interesting and attractive for students

Pairwise and incremental multi-stage alignment of metagenomes: A new proposal

Traditional comparisons between metagenomes are often performed using reference databases as intermediary templates from which to obtain distance metrics. However, in order to fully exploit the potential of the information contained within metagenomes, it becomes of interest to remove any intermediate agent that is prone to introduce errors or biased results. In this work, we perform an analysis over the state of the art methods and deduce that it is necessary to employ fine-grained methods in order to assess similarity between metagenomes. In addition, we propose our developed method for accurate and fast matching of reads.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Helena Béjar: La dejación de España. Katz Editores, Buenos Aires, 2008

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