On regular rotating black holes

The final publication is available at Springer via 10.1007/s10714-016-2166-7Different proposals for regular rotating black hole spacetimes have appeared recently in the literature. However, a rigorous analysis and proof of the regularity of this kind of spacetimes is still lacking. In this note we analyze rotating Kerr-like black hole spacetimes and find the necessary and sufficient conditions for the regularity of all their second order scalar invariants polynomial in the Riemann tensor. We also show that the regularity is linked to a violation of the weak energy conditions around the core of the rotating black hole.Peer ReviewedPostprint (author's final draft

Vocal piano accompaniment: A constant research towards emancipation (2)

This is the second and last article in the series dedicated to the investigation of the evolution of vocal piano accompaniment through history and the role-played by the piano in its relationship with the voice. If the previous chapter focused from the beginnings of piano accompaniment to Franz Schubert, this one will take up again the analysis of the piano part from the last lieder of Franz Schubert to Arnold Schoenberg. The research method used continues to be based on the musical analysis of the piano part, addressing both issues of the piano itself and its link with the text and the vocal part. By means of musical examples of different composers, the article investigates all those aspects that provide evidence of the change in the role of the piano in the correspondence of the piano with the voice and its repercussion on the final result of the work. In this way, we will look at the history of piano accompaniment for voice and see how the influence of Schubert's conception of vocal piano accompaniment materializes in contemporary and later composers, as well as the crucial change in the history of the piano as an accompanying instrument introduced by Schubert. The results and conclusions drawn from the evolution presented in these two articles are presented at the end of the article, based on the different aspects involved in the musical event, such as rhythm, harmony or texture

Understanding the effects of government spending on consumption

Recent evidence on the effect of government spending shocks on consumption cannot be easily reconciled with existing optimizing business cycle models. We extend the standard New Keynesian model to allow for the presence of rule-of-thumb (non-Ricardian) consumers. We show how the interaction of the latter with sticky prices and deficit financing can account for the existing evidence on the effects of government spending. JEL Klassifikation: E32, E62

Understanding the effects of government spending on consumption

Recent evidence on the effect of government spending shocks on consumption cannot be easily reconciled with existing optimizing business cycle models. We extend the standard New Keynesian model to allow for the presence of rule-of-thumb (non-Ricardian) consumers. We show how the interaction of the latter with sticky prices and deficit financing can account for the existing evidence on the effects of government spending. JEL Classification: E32, E62fiscal multiplier, government spending, rule-of-thumb consumers, Taylor rules

Understanding the Effects of Government Spending on Consumption

Recent evidence on the effect of government spending shocks on consumption cannot be easily reconciled with existing optimizing business cycle models. We extend the standard New Keynesian model to allow for the presence of rule-of-thumb (non-Ricardian) consumers. We show how the interaction of the latter with sticky prices and deficit financing can account for the existing evidence on the effects of government spending.Rule-of-Thumb Consumers, Fiscal Multiplier, Government Spending, Taylor Rules

La medicina rural y los equipos directivos : particularidades de la gestión sanitaria en dicho medio

El objetivo perseguido con el presente trabajo es aportar algunos elementos para la reflexión acerca de las características que rodean al ejercicio de nuestra profesión, en estos tiempos y en nuestro medio, en un territorio de predominio rural, desde la perspectiva que aportan los 10 años de experiencia personal del autor en la gestión de atención primaria. No se pretende la exhaustividad, ni tampoco presentar nuestras opiniones como datos objetivos; cabe decir que la fotografía que pueda resultar de lo que sigue, más o menos borrosa, estará además condicionada, aparte de por la experiencia directiva, por 17 años previos de trabajo del que esto escribe como médico rural. Entiendo que es preferible utilizar elementos conocidos para la descripción, y por ello vamos a servirnos del Sector Sanitario de Barbastro para la exposición, en la seguridad de que el lector podrá encontrar más similitudes que diferencias, si compara con otras áreas o sectores del territorio nacional

Ghost imaging with engineered quantum states by Hong-Ou-Mandel interference

Traditional ghost imaging experiments exploit position correlations between correlated states of light. These correlations occur directly in spontaneous parametric down-conversion (SPDC), and in such a scenario, the two-photon state used for ghost imaging is symmetric. Here we perform ghost imaging using an anti-symmetric state, engineering the two-photon state symmetry by means of Hong-Ou-Mandel interference. We use both symmetric and anti-symmetric states and show that the ghost imaging setup configuration results in object-image rotations depending on the state selected. Further, the object and imaging arms employ spatial light modulators for the all-digital control of the projections, being able to dynamically change the measuring technique and the spatial properties of the states under study. Finally, we provide a detailed theory that explains the reported observations.Comment: Published version. 19 pages, 5 figure