Charging a Double Kerr Solution in 5D Einstein--Maxwell--Kalb--Ramond Theory

We consider the low-energy effective action of the 5D Einstein-Maxwell-Kalb-Ramond theory. After compactifying this truncated model on a two-torus and switching off the U(1) vector fields of this theory, we recall a formulation of the resulting three-dimensional action as a double Ernst system coupled to gravity. Further, by applying the so-called normalized Harrison transformation on a generic solution of this double Ernst system we recover the U(1) vector field sector of the theory. Afterward, we compute the field content of the generated charged configuration for the special case when the starting Ernst potentials correspond to a pair of interacting Kerr black holes, obtaining in this way an exact field configuration of the 5D Einstein-Maxwell-Kalb-Ramond theory endowed with effective Coulomb and dipole terms with momenta. Some physical properties of this object are analyzed as well as the effect of the normalized Harrison transformation on the double Kerr seed solution.Comment: 15 pages in latex, revised versio

In the hills, the cities. Political representation and naturalization of the mandate

La representación política en Thomas Hobbes es cuestión de nuda designación. Un ejercicio con el lenguaje. El movimiento básico dentro del cuerpo de la Commonwealth es la designación de un oficial para el pueblo. Esta articulación teorética no es sin embargo suficientemente desarrollada. El objetivo del presente trabajo es sacar provecho de la ayuda que la cuádruple taxonomía sobre representación de A. P. Griffiths y R. Wollheim ofrece, y de la elucidación que presenta Michäel Foessel en torno a lo que es íntimo frente a lo que es privado/lo que es público, empleando ambas como instrumentos que pueden arrojar algo de luz a las intuiciones fundamentales de Hobbes reunidas en su obra principal, el LeviathanPolitical representation in Thomas Hobbes is a matter of bare designation. An exercise with language. The basic movement within the body of the Commonwealth is to appoint someone as officer for the people. This theoretical articulation is not sufficiently developed though. The aim of the present text is to profit from the help the four-fold taxonomy on representation by A.P. Griffiths and R. Wollheim offers, and of the ellucidation Michäel Foessel presents around what is intimate before what is private/ what is public, as instruments that could shed some light onto the fundamental intuitions Hobbes gathered in his main work, the LeviathanEste trabajo se enmarca en el proyecto postdoctoral de investigación On the letter and spirit of imitation: Exemplum and Exemplarity (2018-2020), adscrito al Departamento de Lógica y Filosofía Teórica (Facultad de Filosofía, Universidad Complutense de Madrid - UCM) y bajo la supervisión del Prof. Dr. Ricardo Parellad

The life of others. Marx and Durkheim on suicide and social good(s)

Agencia Estatal de Investigació

Present accelerated expansion of the universe from new Weyl-Integrable gravity approach

We investigate if a recently introduced formulation of general relativity on a Weyl-integrable geometry, contains cosmological solutions exhibiting acceleration in the present cosmic expansion. We derive the general conditions to have acceleration in the expansion of the universe and obtain a particular solution for the Weyl scalar field describing a cosmological model for the present time in concordance with the data combination Planck + WP + BAO + SN.Comment: Version to be published in Eur. Phys. J.

The conformal transformation's controversy: what are we missing?

An alternative interpretation of the conformal transformations of the metric is discussed according to which the latter can be viewed as a mapping among Riemannian and Weyl-integrable spaces. A novel aspect of the conformal transformation's issue is then revealed: these transformations relate complementary geometrical pictures of a same physical reality, so that, the question about which is the physical conformal frame, does not arise. In addition, arguments are given which point out that, unless a clear statement of what is understood by "equivalence of frames" is made, the issue is a semantic one. For definiteness, an intuitively "natural" statement of conformal equivalence is given, which is associated with conformal invariance of the field equations. Under this particular reading, equivalence can take place only if the metric is defined up to a conformal equivalence class. A concrete example of a conformal-invariant theory of gravity is then explored. Since Brans-Dicke theory is not conformally invariant, then the Jordan's and Einstein's frames of the theory are not equivalent. Otherwise, in view of the alternative approach proposed here, these frames represent complementary geometrical descriptions of a same phenomenon. The different points of view existing in the literature are critically scrutinized on the light of the new arguments.Comment: 17 pages, no figures. version accepted by General Relativity and Gravitation journa

Using plantar pressure for free-living posture recognition and sedentary behaviour monitoring

Health authorities in numerous countries and even the World Health Organization (WHO) are concerned with low levels of physical activity and increasing sedentary behaviour amongst the general population. In fact, emerging evidences identify sedentary behaviour as a ubiquitous characteristic of contemporary lifestyles. This has major implications for the general health of people worldwide particularly for the prevalence of non-communicable conditions (NCDs) such as cardiovascular disease, diabetes and cancer and their risk factors such as raised blood pressure, raised blood sugar and overweight. Moreover, sedentary time appears to be uniquely associated with health risks independent of physical activity intensity levels. However, habitual sedentary behaviour may prove complex to be accurately measured as it occurs across different domains, including work, transport, domestic duties and even lei¬sure. Since sedentary behaviour is mostly reflect as too much sitting, one of the main concerns is being able to distinguish among different activities, such as sitting and standing. Widely used devices such as accelerometer-based activity monitors have a limited ability to detect sedentary activities accurately. Thus, there is a need of a viable large-scale method to efficiently monitor sedentary behaviour. This thesis proposes and demonstrates how a plantar pressure based wearable device and machine learning classification techniques have significant capability to monitor daily life sedentary behaviour. Firstly, an in-depth review of research and market ready plantar pressure and force technologies is performed to assess their measurement capabilities and limitations to measure sedentary behaviour. Afterwards, a novel methodology for measuring daily life sedentary behaviour using plantar pressure data and a machine learning predictive model is developed. The proposed model and its algorithm are constructed using a dataset of 20 participants collected at both laboratory-based and free-living conditions. Sitting and standing variations are included in the analysis as well as the addition of a potential novel activities, such as leaning. Video footage is continuously collected using of a wearable camera as an equivalent of direct observation to allow the labelling of the training data for the machine learning model. The optimal parameters of the model such as feature set, epoch length, type of classifier is determined by experimenting with multiple iterations. Different number and location of plantar pressure sensors are explored to determine the optimal trade-off between low computational cost and accurate performance. The model s performance is calculated using both subject dependent and subject independent validation by performing 10-fold stratified cross-validation and leave-one-user-out validation respectively. Furthermore, the proposed model activity performance for daily life monitoring is validated against the current criterion (i.e. direct observation) and against the de facto standard, the activPAL. The results show that the proposed machine learning classification model exhibits excel-lent recall rates of 98.83% with subject dependent training and 95.93% with independent training. This work sets the groundwork for developing a future plantar pressure wearable device for daily life sedentary behaviour monitoring in free-living conditions that uses the proposed ma-chine leaning classification model. Moreover, this research also considers important design characteristics of wearable devices such as low computational cost and improved performance, addressing the current gap in the physical activity and sedentary behaviour wearable market

El estado actual de la teoría macroeconómica

This paper describes the evolution of macroeconomic theory in both closed and open economies. In the first section we present the evolution of the theory of a closed economy‚economies that do not have international trade; nor do it have links to the international financial markets. Since Keynes, the neoclassical synthesis, the monetarists, the revolution of rational expectations, until the most recent literature such as the real business cycle theory and the new Keynesian economics. In the second section we present the evolution of the theory of an open economy. Since Hume, the work of Mundell and Fleming, the monetary approach of the balance of payments, the overshooting and the Open Economy Macroeconomics by Rudiger Dornbusch, until the most recent literature developed in the Foundations of International Macroeconomics by Obstfeld and Rogoff. As is evident, this presentation is not intended to be comprehensive in its coverage of the topics.

Propuesta de modelo estratégico para la creación de un restaurante de comida saludable

La idea de negocios que se presenta en este proyecto está enfocada en cubrir la necesidad de una alimentación saludable para las personas que buscan esta opción, pero además, también busca cubrir la necesidad básica de alimentación para las personas que por cuestiones laborales o escolares no pueden alimentarse en sus hogares y por consecuencia deben consumir sus alimentos en establecimientos comerciales, lo cual en muchas ocasiones resulta ser una opción no saludable y además costosa. La idea de negocios que se va a desarrollar es la de un restaurante que ofrezca un menú de comida saludable que cubra las necesidades nutricionales generales para cualquier persona, pero además, que también ofrezca platillos adicionales al menú distintos cada día. Un punto muy importante de la idea de negocios es que el servicio que se brinde debe ser rápido, limpio, cortés y a un precio justo; en virtud de que el servicio se convierta en un punto distintivo del restaurante. Cabe señalar que los servicios del restaurante solo incluirán el desayuno y la comida. El nombre comercial del establecimiento será ¡SANISIMO! Restaurante, el cual hace referencia al tipo de productos que serán ofrecidos. La estrategias de promoción que llevara a cabo el restaurante están descritas en la tabla 14; sin embargo, cabe señalar que gran parte del posicionamiento del restaurante dependerá de la diferenciación que este tiene del resto de la competencia, es decir, de sus ventajas competitivas; por tal motivo es muy importante tomar en cuenta los servicios que hacen diferente al restaurante, los cuales se enlistan a continuación: 1. Ser un restaurante de comida a la carta especializado en platillos y alimentos saludables. 2. Ofrecer platillos y alimentos especiales para las personas que tengan algún tipo de dieta o régimen alimenticio. 3. Servicio de asesoría nutricional gratuita para los clientes del restáurate. 4. Venta de comida “rápida” como sándwiches, baguettes, pastas, ensaladas, zumos, entre otros; elaborados con ingredientes y productos saludables. 5. Servicios de comedor para los empleados de las empresas con las que se tenga convenio. De acuerdo con Weinberger Villarán (2009) el utilizar las ventajas competitivas para diferenciarse de la competencia y tratar de ser recordado por algún atributo en especial, se puede considerar como una estrategia de posicionamiento, dicha estrategia también será utilizada por el restaurante mediante las estrategias de promoción, con la finalidad de conocer si existe una demanda lo suficientemente grande que valore el beneficio de los atributos distintivos del restaurante o si es necesario cambiar algún atributo de los servicios del restaurante