Sudden violation of the CHSH inequality in a two qubits system

I study the dynamics of the violation of the CHSH inequality for two qubits interacting with a common zero-temperature non-Markovian environment. I demonstrate sudden violation of the inequality for two qubits initially prepared in a factorized state. Due to the strong coupling between the qubits and the reservoir, the dynamics is characterized by numerous sharp revivals. Furthermore I focus on a more realistic physical system in which the spontaneous emission for the qubits is taken into account. When including spontaneous emission even for small decay parameters, revivals in the violation are heavily damped out. If the decay rates exceed a certain threshold, the inequality turns out to be always satisfied.Comment: Accepted by Physica Scripta as part of the Proceedings of CEWQO0

Non-Markovianity and Quantum Correlations in Qubit-Systems

In this Thesis I discuss the exact dynamics of simple non-Markovian systems. I focus on fundamental questions at the core of non-Markovian theory and investigate the dynamics of quantum correlations under non-Markovian decoherence. In the first context I present the connection between two different non-Markovian approaches, and compare two distinct definitions of non-Markovianity. The general aim is to characterize in exemplary cases which part of the environment is responsible for the feedback of information typical of non- Markovian dynamics. I also show how such a feedback of information is not always described by certain types of master equations commonly used to tackle non-Markovian dynamics. In the second context I characterize the dynamics of two qubits in a common non-Markovian reservoir, and introduce a new dynamical effect in a wellknown model, i.e., two qubits under depolarizing channels. In the first model the exact solution of the dynamics is found, and the entanglement behavior is extensively studied. The non-Markovianity of the reservoir and reservoirmediated-interaction between the qubits cause non-trivial dynamical features. The dynamical interplay between different types of correlations is also investigated. In the second model the study of quantum and classical correlations demonstrates the existence of a new effect: the sudden transition between classical and quantum decoherence. This phenomenon involves the complete preservation of the initial quantum correlations for long intervals of time of the order of the relaxation time of the system.Siirretty Doriast

An overview of cultural relations between Mexico and Italy (since the XVI century until now)

En el artículo se propone el análisis de las relaciones culturales entre México e Italia y la primera «oficialización» de las mismas. Se ha considerado necesario analizar, antes de todo, el carácter distintivo de los conceptos de relaciones culturales y de diplomacia cultural y su evolución. Hay que ir hasta el siglo XIX para poder hablar del origen de la diplomacia cultural entre México e Italia, con la firma del primer acuerdo cultural de carácter bilateral a nivel gubernamental. Sin embargo, antes de profundizar el desarrollo en el siglo XX de la diplomacia cultural, se pretende ofrecer una pincelada de la difusión espontánea de las relaciones culturales desde los primeros encuentros entre mexicanos e italianos en el siglo XVII.The aim of this article is to analyse the cultural relations between Italy and Mexico. In particular, it seeks to examine the period in which these cultural relations were regularised and placed on an official footing. In order to understand Italian-Mexican cultural relations it has been considered necessary to focus, first of all, the way in which the twin concepts of cultural relations and cultural diplomacy developed. Moreover, to speak about cultural relations at a political level, when cultural diplomacy properly began, we will need to go back to the XIX century, when the first cultural bilateral agreements between the two governments were stipulated. However, in the concluding section, before going deeply into the complex field of cultural diplomacy, we will try to outline the flourishing and spontaneous cultural relationship developed after the firts approaches between Mexicans and Italians during the XVII century.Publicad

Tina Modotti: An intense life between Europe and America

El artículo trata de la rocambolesca trayectoria vital de la célebre fotógrafa y apasionada luchadora Tina Modotti, transcurrida entre el continente americano y europeo durante los cruciales años veinte y treinta del siglo XX . Lo que se intenta hacer es sacar a la luz la labor realizada por Modotti en España durante la Guerra Civil, en cuanto momento más desconocido en las biografías a ella dedicadas. Modotti, compañera sentimental del comandante «Carlos J. Contreras», trabajó para el Socorro Rojo Internacional, desempeñando decisivas y peligrosas funciones como enfermera, a lado de Matilde Landa y también como periodista para la revista Ayuda. Entró así en contacto con varios exponentes de la cultura española y entre ellos con Miguel Hernández de cuyo libro, Viento del Pueblo fue promotora. Finalmente lo que se pretende es presentar la vida de Modotti desmitificándola y restituyéndole el papel que tuvo en España y en general en el ámbito del movimiento internacionalista.The article is about the interesting life of the famous photographer and revolutionary Tina Modotti who lived between the American and European continent during the crucial time of the twenties and thirties in the 20th century. The aim of the text is to high light the work done by Modotti in Spain during the Civil War, as this was a virturally unknown period in the biographies about her. Modotti, the paramour of the commandant -Carlos J. Contreras», worked for the International Red Aid and carried out important and dangerous missions as a nurse alongside Matilde Landa, and also as a journalist for the journal Ayuda. In this way she carne into contad with many representative people of the Spanish culture, among them, Miguel Hernández who was a promoter of the publication Viento del pueblo. Finally, with this paper we would like to produce a demystified biography of Modotti in order to highlight the historie role that she truly played both in Spain as well as in tihe fíeld of the internationalist movement.Publicad

Legitimizing the women’s international solidarity: the Red Aid

La evolución del concepto de solidaridad introduce la temática central de este artículo: la solidaridad internacional de matriz comunista y el papel de las mujeres. El valor políticocivil, más que el asistencial y benéfico de la solidaridad es lo que se pretende subrayar, así como su relación preferente con la historia de las mujeres. En el contexto de las convulsas décadas de los veinte y treinta del siglo XX en Europa y en España se analizará, en el marco de la organización cominterniana del Socorro Rojo Internacional y más en general en el contexto de la internacionalización de la solidaridad femenina, la relevante labor llevada a cabo por las mujeres en las tareas de ayuda y socorro.The evolution of the concept of solidarity introduces the central topic of this article: the relationship between the solidarity of international communism and the role of women. As well as we hope to draw attention not only to the aspects of charity and welfare, related to solidarity, but to the political and civic values of solidarity and its primary relationship with women’s history. To do this, we will analyze the relevant work carried out by women in the areas of aid and solidarity within the context of the convulsive decades of the Twenties and Thirties in the 20th Century in Europe and in Spain. Our study will focus upon the Comintern organization, the International Red Aid (IRA), and more generally the field of the internationalization of female solidarity.Publicad

Visibilidad e instrumentalización: el caso de las mujeres

Ponencia presentada a la XV Semana de Ética y Filosofía Política, bajo el título "Tradición e Innovación en Ética y Filosofía Política"Enviad

High throughput microbalance and methods of using same

The method and apparatus is particularly adapted for providing microbalance measurement of solid materials as part of a combinatorial research program. The method and apparatus contemplate monitoring the response of a resonator holding a sample and correlating the response with mass change in the samples

Dynamical role of system-environment correlations in non-Markovian dynamics

We analyse the role played by system-environment correlations in the emergence of non-Markovian dynamics. By working within the framework developed in Breuer et al., Phys. Rev. Lett. 103, 210401 (2009), we unveil a fundamental connection between non-Markovian behaviour and dynamics of system-environment correlations. We derive an upper bound to the rate of change of the distinguishability between different states of the system that explicitly depends on the development and establishment of correlations between system and environment. We illustrate our results using a fully solvable spin-chain model, which allows us to gain insight on the mechanisms triggering non-Markovian evolution.Comment: 5 pages, 2 figure