Se repasa brevemente la historia y las finanzas islandesas de manera diacrónica. Se presenta a Islandia como bastión del estallido de la crisis financiera internacional que comienza a gestarse a principios del siglo XXI y cuyo origen se hace evidente en la fecha simbólica del año 2008. Se analizan las razones fundamentales de esta crisis, centrandonos en las particularidades de la estructura económica islandesa. Se consideran las diferencias y parecidos de esta situación en relación a algunos otros países en similares circunstancias. Se estudia el caso del banco Icesave. Se considera la repercusión que la crisis experimentada por Islandia tiene en el ámbito internacional, especialmente en los inversores extranjeros y en los conflictos jurídicos surgidos a raíz de las medidas adoptadas por el gobierno islandés para sacar al país de la bancarrota. -- Icelandic history and diachronically finances are briefly reviewed. Iceland is presented as a bastion of the outbreak of the global financial crisis begins to take shape in the early twenty-first century and whose origin is evident in the symbolic date of 2008. The main reasons for this crisis are analyzed, focusing on the particularitie
Spanish: La Cosmología esta progresando a pasos agigantados gracias a la cantidad espectacular de datos observacionales que se obtienen tanto de los experimentos en tierra como satélites. Un papel fundamental es desempeñdo por las observaciones del Fondo Cósmico de Microondas (CMB por sus siglas en inglé, Cosmic Microwave Background), la cual nos proporciona la prueba observacional más directa de los inicios del Universo. Las observaciones de la temperatura y las anisotropías en el CMB han jugado un papel fundamental en la definición del modelo cosmológico. Esta contribución tiene como objetivo resumir algunos de los conceptos básicos que hay detrás de la física del CMB. La mayor parte de los ingredientes del modelo cosmológico estándar son poco conocidos en términos de la física fundamental, por efemplo, la materia oscura y la energía oscura. Se discute cómo las observaciones actuales abordan algunas de estas cuestiones. English: The cosmic microwave background (CMB) provides the most direct observational test of the early universe. The observations of the temperature anisotropies in the CMB have played a key role in defining the cosmological model. This contribution aims to summa
This text is based on a commemorative lecture dedicated to Enrique Gaviola, delivered on August 14, 2025, at the Córdoba Astronomical Observatory on the occasion of the 125th anniversary of his birth. The event was organized by the OAC, IATE, the Gaviola Institute, and FAMAF of the National University of Córdoba. The paper presents a personal perspective on Gaviola's life, scientific contributions, and legacy, drawing upon documents from the Gaviola Archive at the Balseiro Institute as well as testimonies from colleagues who knew him. -- El presente texto se basa en la conferencia de homenaje a Enrique Gaviola, dictada el 14 de agosto de 2025 en el Observatorio Astronómico de Córdoba, con motivo del 125o aniversario de su nacimiento. La actividad fue organizada por el OAC, el IATE, el Instituto Gaviola y la FAMAF de la Universidad Nacional de Córdoba. El trabajo ofrece una reflexión personal sobre su vida, su obra y su legado, a partir de los documentos del Archivo Gaviola del Instituto Balseiro y de los testimonios de colegas que lo conocieron.
Around year 2000 the centenary of Planck's thermal radiation formula awakened interest in the origins of quantum theory, traditionally traced back to the Planck's conference on 14 December 1900 at the Berlin Academy of Sciences. A lot of more accurate historical reconstructions, conducted under the stimulus of that recurrence, placed the birth date of quantum theory in March 1905 when Einstein advanced his light quantum hypothesis. Both interpretations are yet controversial, but science historians agree on one point: the emergence of quantum theory from a presumed "crisis" of classical physics is a myth with scarce adherence to the historical truth. This article, written in Italian language, was originally presented in connection with the celebration of the World Year of Phyics 2005 with the aim of bringing these scholarly theses to a wider audience. --- Tradizionalmente la nascita della teoria quantistica viene fatta risalire al 14 dicembre 1900, quando Planck presentò all'Accademia delle Scienze di Berlino la dimostrazione della formula della radiazione termica. Numerose ricostruzioni storiche più accurate, effettuate nel periodo intorno al 2000 sotto lo stimolo dell'interesse pe
We consider the free boundary problem for a two-dimensional, incompressible, perfect, irrotational liquid drop of nearly circular shape with capillarity: that is, we consider the 2D version of the 3D capillary drop problem treated in Baldi-Julin-La Manna [11] and Baldi-La Manna-La Scala [12]. In particular, we derive its Craig-Sulem formulation firstly over the circle, then over the one-dimensional flat torus; the arising equations are similar to the pure capillary Water Waves for the ocean problem, apart from conformal factors and additional terms due to curvature terms. Then, we show its Hamiltonian structure and we derive constants of motions from symmetries, one of which is the invariance by the torus action. Thanks to this invariance, we show the existence of orbits of rotating wave solutions (which are the analogous of travelling waves of the ocean problem) by bifurcation from multiple eigenvalues in the spirit of Moser-Weinstein [44, 56] and Craig-Nicholls [22] variational approaches; in particular, we can parametrize such orbits by the angular momentum, and for each value of it they are unique. This will imply that each orbit is generated by symmetric rotating waves.
Large language models, such as the well-known ChatGPT, have brought about an unexpected revolution in the field of artificial intelligence. On the one hand, they have numerous practical applications and enormous potential still to be explored. On the other hand, they are also the subject of debate from scientific, philosophical, and social perspectives: there are doubts about the exact mechanisms of their functioning and their actual capacity for language comprehension, and their applications raise ethical dilemmas. In this chapter, we describe how this technology has been developed and the fundamentals of its operation, allowing us to better understand its capabilities and limitations and to introduce some of the main debates surrounding its development and use. -- Los grandes modelos de lenguaje, como el conocido ChatGPT, han supuesto una inesperada revolución en el ámbito de la inteligencia artificial. Por un lado, cuentan con multitud de aplicaciones prácticas y un enorme potencial todavía por explorar. Por otro lado, son también objeto de debate, tanto desde el punto de vista científico y filosófico como social: hay dudas sobre los mecanismos exactos de su funcionamiento y su
El uso de las redes sociales tiene consecuencias positivas o negativas en la participación ciudadana? La gran parte de los intentos por responder a esta pregunta incluyen datos de la opinión pública de los Estados Unidos, por lo que nosotros ofrecemos un estudio sobre un caso significativo de México, donde un candidato independiente utilizó las redes sociales para comunicarse con el público y rehuyó de los medios de comunicación tradicionales. Dicho candidato, conocido como "El Bronco", ganó la carrera por la gubernatura del estado al derrotar a los candidatos de los partidos tradicionales. Además, generó una participación ciudadana que se ha mantenido más allá del día de las elecciones. En nuestra investigación analizamos más de 750 mil mensajes, comentarios y respuestas durante más de tres años de interacciones en la página pública de Facebook de "El Bronco". Examinamos y demostramos que las redes sociales pueden utilizarse para dar cabida a una gran cantidad de interacciones ciudadanas sobre la vida pública más allá de un acontecimiento político. Does social media use have a positive or negative impact on civic engagement? The "slacktivism hypothesis" holds that if citizens use
In this expository article, we study the relation between the boolean functions and the hypercontractivity theorems of Aline Bonami. We focus on the social choice theory, and present some of the most important results in the area, such as the Friedgut-Kalai-Naor (FKN) and the Kahn-Kalai-Linial (KKL) theorems, and the famous Fourier Entropy/Influence conjecture. -- En este artículo expositivo estudiamos la relación entre las funciones booleanas y los teoremas de hipercontractividad de Aline Bonami. Nos concentramos en la teoría de la elección social, y presentamos algunos de los resultados más importantes en el área como los teoremas de Friedgut-Kalai-Naor (FKN) y de Kahn-Kalai-Linial (KKL), y la famosa conjetura Entropíıa de Fourier/Influencia.
In the present paper, we extend the study of Del Popolo (2010) to determine the slope of the inner density profile of galaxy haloes with different morphologies. We study how galaxy morphology changes the relation between the inner slope of the galaxy halo density profile, $α$, and the stellar mass, $M_{*}$, or rotation velocity $V_{\rm rot}$. For this, we use the model of Del Popolo (2009) in combination with observed data from the Romanowsky \& Fall (2012) sample of elliptical and spiral galaxies, the Local Group sample compiled by McConnachie (2012), and the simulation results by Cloet-Osselaer et al. (2014). We find that the slope $α$ flattens monotonically, from $α\simeq -1 $ at $V_{\rm rot} \simeq 250$ km/s, to $α\simeq 0 $. After $V_{\rm rot}\simeq 25$ km/s the slope starts to steepen. The steepening happens in the mass range dominated by non-rotationally supported galaxies (e.g., dSphs) and depends on the level of offset in the angular momentum of rotationally and non-rotationally dominated galaxies. The steepening is a consequence of the decrease in baryons content, and angular momentum in spheroidal dwarf galaxies. We finally compare our result to the SPH simulations o
The identity of the famous place of La Mancha appearing at the Quijote is an unknown with a history almost as long as that of the famous book by Miguel de Cervantes. This work analyzes data obtained from a Geographic Information System and compares the results with those of the previous works. Three different variables with two possible values each are considered: time or space data, 3 or 4 reference points, and the commonly used distances to the place of La Mancha or a set of recently proposed ones. The village in the Campo de Montiel which is closest to be the place of La Mancha happens to be Carrizosa or Villanueva de los Infantes, depending on the configuration, with the latter being the solution for the configuration in which the relative errors are the smallest and the second candidate village is furthest from the first. ----- La identidad del famoso lugar de la Mancha que aparece en El Quijote es una incógnita con una historia casi tan larga como la publicación de la famosa obra de Miguel de Cervantes. Este trabajo analiza datos obtenidos mediante un Sistema de Información Geográfica y compara los resultados con los de los trabajos anteriores. Se consideran tres variables di
A statistical analysis of an electoral quick count based on the total count of votes in the election of the State of Mexico's governor in 2017 is performed in order to verify precision, confidence level of interval estimations, possible bias and derived conclusions therein, with the main purpose of checking compliance with the objectives of such statistical procedure. ----- Se realiza un análisis estadístico de las estimaciones del conteo rápido institucional desde la perspectiva ideal de los resultados de los cómputos distritales de la elección de gobernador del Estado de México del año 2017, particularmente aspectos como la precisión de las estimaciones, el nivel de confianza de los intervalos, el posible sesgo respecto al cómputo distrital y las conclusiones que se derivaron y reportaron, con el objetivo de determinar el grado de cumplimiento de los objetivos de este ejercicio estadístico de carácter informativo.
The "Mathematics in Three Acts" approach, proposed by Dan Meyer, aims to transform the teaching of mathematics through a model that encourages active student participation, fostering creativity, problem-solving, and metacognition. This study explores the implementation of this approach in a mathematics contest for secondary school students, evaluating its impact on various key competencies. Aspects such as mathematical creativity, problem-solving skills, metacognitive abilities, and students' perceptions of mathematics are examined. The results show that the approach contributes to the development of creative skills, improves understanding and problem-solving abilities, and increases student motivation and confidence. However, areas for improvement are also identified, particularly in the justification of procedures and cognitive flexibility. This study highlights the effectiveness of the "Mathematics in Three Acts" approach as an innovative methodology that fosters more meaningful, reflective, and autonomous learning, suggesting its potential to transform mathematics teaching in diverse educational contexts.
In the current paper, we further develop the model for the migration of planets introduced in Del Popolo et al. (2001) and extended to time-dependent accretion discs in Del Popolo and Eksi (2002). We use a method developed by Stepinski and Valageas (1996, 1997), that is able to simultaneously follow the evolution of gas and solid particles for up to $10^7 {\rm yr}$. The disc model is coupled to the migration model introduced in Del Popolo et al. (2001) in order to obtain the migration rate of the planet in the planetesimal disc. We find that in the case of discs having total mass of $10^{-3}-0.1 M_{\odot}$, and $0.1<α<0.0001$, planets can migrate inward a large distance while if $M<10^{-3} M_{\odot}$ the planets remain almost in their initial position for $0.1<α<0.01$ and only in the case $α<0.001$ the planets move to a minimum value of orbital radius of $\simeq 2 {\rm AU}$. The model gives a good description of the observed distribution of planets in the period range 0-20 days.
Presentamos una introduccion a los conceptos basicos del rompimiento de la simetria electrodebil y la fisica del Higgs dentro del Modelo Estandar y sus extensiones supersimetricas. Se presenta tambien una breve perspectiva general de mecanismos alternativos del rompimiento de la simetria. Ademas de las bases teoricas, se discute el estado actual de la fisica experimental del Higgs y sus implicaciones para futuros experimentos en el LHC y en colisionadores lineales e+e-.
The title of this essay, Induced perversity, La perversidad inducida (in Spanish), refers to the side effects of sharing information on social media when it turns out to be false; or when judgments are made about people, events, companies, or facts that can produce effects often leading to consequences that were not initially foreseen. In digital environments, on the internet of linked data, harrassment politics and the cancellation culture are not isolated phenomena; they should be related to the evolution of the web, the emergence of the platform-driven economy, and the change of users' behaviour. Risks are not only a product of technology or the emergence of artificial intelligence. Ethical problems arise in a hybrid society, where the adaptation of human behavior to human-machine interaction (HMI), and the ethical, social, and legal ways of regulating them have yet to be learned. This contribution complements the contents of the article: La regimentacion tecnologica. Inteligencia artificial, fascismo, agresionn y sociedad democratica. TeKnoKultura. Revista de Cultura Digital y Movimientos Sociales, no 22, 2-2025, monografico sobre poder y politica de la inteligencia artificial.
In the current paper, we further improved the model for the migration of planets introduced in Del Popolo et al. (2001) and extended to time-dependent planetesimal accretion disks in Del Popolo and Eksi (2002). In the current study, the assumption of Del Popolo and Eksi (2002), that the surface density in planetesimals is proportional to that of gas, is released. In order to obtain the evolution of planetesimal density, we use a method developed in Stepinski and Valageas (1997) which is able to simultaneously follow the evolution of gas and solid particles for up to 10^7 yrs. Then, the disk model is coupled to migration model introduced in Del Popolo et al. (2001) in order to obtain the migration rate of the planet in the planetesimal. We find that the properties of solids known to exist in protoplanetary systems, together with reasonable density profiles for the disk, lead to a characteristic radius in the range 0.03-0.2 AU for the final semi-major axis of the giant planet.
The territory of La Mancha, its rural areas, and its landscapes suffer a kind of atherosclerosis ("the silent killer") because of the increase in artificial surfaces, the fragmentation of the countryside by various infrastructures, the abandonment of small and medium-sized farms and the loss of agricultural, material, and intangible heritage. At the same time, agricultural industrialization hides, behind a supposed productive efficiency, the deterioration of the quantitative and qualitative ecological status of surface and groundwater bodies, and causes air pollution, greenhouse gas emissions, loss of soil fertility, drainage and plowing of wetlands, forgetfulness of the ancestral environmental heritage, of the emergence of uses and customs of collective self-government and reduction of the adaptive capacity of traditional agroecosystems. This work aims, firstly, to shed light on the true costs of the main causes of environmental degradation in the territory of La Mancha, while deteriorating relations between rural and urban areas and determining the loss of territorial identity of La Mancha. the population. In addition, drivers of change toward a more sustainable social, economic,
Clustering algorithms or methods for GPS trajectories are in constant evolution due to the interest aroused in part of the scientific community. With the development of clustering algorithms considered traditional, improvements to these algorithms and even unique methods considered as "novelty" for science have emerged. This work aims to analyze the scientific production that exists around the topic "GPS trajectory clustering" by means of bibliometrics. Therefore, a total of 559 articles from the main collection of Scopus were analyzed, previously filtering the generated sample to discard any article that does not have a direct relationship with the topic to be analyzed. This analysis establishes an ideal environment for other disciplines and researchers, since it provides a current state of the trend of the subject of study in their field of research. -- Los algoritmos o métodos de agrupamiento para trayectorias GPS se encuentran en constante evolución debido al interés que despierta en parte de la comunidad científica. Con el desarrollo de los algoritmos de agrupamiento considerados tradicionales han surgido mejoras a estos algoritmos e incluso métodos únicos considerados como "n
Due to the limited amount of resources available for the next release of the current product under development not all stakeholders requests can be included in the next product to deliver. This optimization problem, known as the Next Release Problem (NRP), has customers satisfaction and development costs as the basic optimization objectives, and has been the subject of many research works. However, there are additional issues that deserve to be considered and included in the definition of the NRP, such as supplementary optimization objectives including the elicited properties about the requirements, or the analysis of the non-dominated solution sets found to decide which solution is preferred. This paper presents a generic formulation for this problem that allows the management of the currently agreed properties and relationships between requirements. It provides an open formulation that is capable of growing as the scope of the NRP grows. We specify how our proposal can be used in software product projects when requirements selection has to be performed. We also describe how our formulation has been instantiated to cover previous solving approaches to this problem, using six case
We study the pseudo phase-space density, $ρ(r)/σ^3(r)$, of $Λ$CDM dark matter halos with and without baryons (baryons+DM, and pure DM), by using the model introduced in Del Popolo (2009), which takes into account the effect of dynamical friction, ordered and random angular momentum, baryons adiabatic contraction and dark matter baryons interplay. We examine the radial dependence of $ρ(r)/σ^3(r)$ over 9 orders of magnitude in radius for structures on galactic and cluster of galaxies scales. We find that $ρ(r)/σ^3(r)$ is approximately a power-law only in the range of halo radius resolved by current simulations (down to 0.1% of the virial radius) while it has a non-power law behavior below the quoted scale, with inner profiles changing with mass. The non-power-law behavior is more evident for halos constituted both of dark matter and baryons while halos constituted just of dark matter and with angular momentum chosen to reproduce a Navarro-Frenk-White (NFW) density profile, are characterized by an approximately power-law behavior. The results of the present paper lead to conclude that density profiles of the NFW type are compatible with a power-law behavior of $ρ(r)/σ^3(r)$, while tho