Identification of strongly correlated states of cold atoms

Treballs Finals de Grau de Física, Facultat de Física, Universitat de Barcelona, Curs: 2017, Tutora: Núria Barberán FalconUsing a small sample of cold bosonic atoms submitted to a strong artificial magnetic field, we obtain the ground state of the system in the lowest Landau level. Our goal is to identify the ground state obtained with the known Laughlin state. The calculations have been done by exact diagonalization of the corresponding Hamiltonian. The obtained ground state is a strongly correlated state with zero interaction. This state shows all of the characteristics familiar from the fractional quantum Hall effect

L’amic, prova’l primer ans que l’hages menester: Classical Sources of a Catalan proverb included in Sebastià Farnés’ Paremiologia catalana comparada

This paper aims to investigate the Classical proverbs listed as equivalents to the Catalan proverb L’amic, prova’l primer ans que l’hages menester by Sebastià Farnés in his volume entitled Paremiologia catalana comparada. In this paper, I will establish these Classical proverbs’ sources, consider their authenticity and correspondence with this Catalan proverb, and increase the number of Classical sources, since this Catalan proverb bears witness to its Classical tradition and is related to philosophical and literary passages that can be considered as previous manifestations of this tradition. These Greek and Latin passages are compiled and compared so as to determine the different ways in which the idea included in this Catalan proverb was expressed over time. The conclusion is that the consideration about friendship presented by this proverb is embedded into a long textual/ideological tradition which ultimately refers to the sage Solon, the poet Theognis and the philosopher Theofrast, although there may be connections with the Judeo-Christian tradition as well.This paper aims to investigate the Classical proverbs listed as equivalents to the Catalan proverb L’amic, prova’l primer ans que l’hages menester by Sebastià Farnés in his volume entitled Paremiologia catalana comparada. In this paper, I will establish these Classical proverbs’ sources, consider their authenticity and correspondence with this Catalan proverb, and increase the number of Classical sources, since this Catalan proverb bears witness to its Classical tradition and is related to philosophical and literary passages that can be considered as previous manifestations of this tradition. These Greek and Latin passages are compiled and compared so as to determine the different ways in which the idea included in this Catalan proverb was expressed over time. The conclusion is that the consideration about friendship presented by this proverb is embedded into a long textual/ideological tradition which ultimately refers to the sage Solon, the poet Theognis and the philosopher Theofrast, although there may be connections with the Judeo-Christian tradition as well

Suffer, Bear, and Endure: Latin Sources of Resignation in Spanish Proverbs

Spanish refranero forms a sort of code whose aim is to guide and control the conduct of the members of the linguistic community that has coined these proverbs and uses them. A great part of the ideology that can be gathered from Spanish proverbs was already present in Classical culture. Therefore my overall objective is to trace the Classical precedents of Spanish proverbs. Particularly this paper aims to find in Latin language and literature formal or ideological precursors of a certain amount of Spanish proverbs concerning the stoic attitude we should take in order to confront misfortune. This attitude is based on facing with resignation what fate holds in store for us and it results in accepting pain as an essential part of human existence, promoting a conformist behavior that restrains aspirations to better conditions and makes it unlikely that the establishment will be broken.Spanish refranero forms a sort of code whose aim is to guide and control the conduct of the members of the linguistic community that has coined these proverbs and uses them. A great part of the ideology that can be gathered from Spanish proverbs was already present in Classical culture. Therefore my overall objective is to trace the Classical precedents of Spanish proverbs. Particularly this paper aims to find in Latin language and literature formal or ideological precursors of a certain amount of Spanish proverbs concerning the stoic attitude we should take in order to confront misfortune. This attitude is based on facing with resignation what fate holds in store for us and it results in accepting pain as an essential part of human existence, promoting a conformist behavior that restrains aspirations to better conditions and makes it unlikely that the establishment will be broken

Approaching to student intellectual debates: revolutionary representations in some university cultural magazines (Bahía Blanca, 1960-1961)

La creación de la Universidad Nacional del Sur en Bahía Blanca en 1956 se concretó en el inestable escenario político heredado del derrocamiento de Juan Domingo Perón en septiembre del año anterior. Los estudiantes que se congregaron en el nuevo espacio educativo forjaron sus ideas, intereses y aspiraciones al calor del debate en torno al fenómeno peronista pero, también, permeados por las noticias acerca de los hechos internacionales. Entre estos últimos, la Revolución Cubana ha sido identificada como uno de los elementos vitales de la radicalización ideológica de algunas formaciones políticas durante los años 60 y la década de 1970, a la vez que se ha convertido en un tópico frecuentemente utilizado en investigaciones acerca de los movimientos y las prácticas de lucha armada en América Latina. Este trabajo se propone abordar las representaciones revolucionarias que se pusieron de manifiesto, de manera muy temprana, en algunas de las revistas culturales universitarias de la ciudad. De este modo, intenta dar cuenta del funcionamiento del éxito cubano como uno de los paradigmas a través de los cuales se interpretaron los problemas de la dirigencia estudiantil ligada a la novel universidad, y sobre los que se sentaron las pautas que debían orientar la definición de la praxis futura.The creation of the Universidad Nacional del Sur in Bahia Blanca in 1956 took shape in the unstable political scenario inherited from the overthrow of Juan Domingo Peron in September last year. Students gathered in the new educational space shaped their ideas, interests and aspirations in the heat of debate over peronist phenomenon but also permeated by the news about international events. Among the latter, the Cuban Revolution has been identified as one of the vital elements of the ideological radicalization of some political groups during the 60's and the 70's has been frequently used when researching the movements and practices of armed struggle in Latin America. This paper intends to consider the early representations of the Cuban Revolution presented in some of the university cultural magazines of Bahia Blanca. The objective is to account for its performance as a paradigm through which the context of student leaders at the Universidad Nacional del Sur was analized. At the same time, these representations set the guidelines to define their future practices.Fil: López Pascual, Juliana. Universidad Nacional del Sur. Departamento de Humanidades. Centro de Est. Regionales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

SWIPT techniques for multiuser MIMO broadcast systems

In this paper, we present an approach to solve the nonconvex optimization problem that arises when designing the transmit covariance matrices in multiuser multiple-input multiple-output (MIMO) broadcast networks implementing simultaneous wireless information and power transfer (SWIPT). The MIMO SWIPT design is formulated as a nonconvex optimization problem in which system sum rate is optimized considering per-user harvesting constraints. Two different approaches are proposed. The first approach is based on a classical gradient-based method for constrained optimization. The second approach is based on difference of convex (DC) programming. The idea behind this approach is to obtain a convex function that approximates the nonconvex objective and, then, solve a series of convex subproblems that, eventually, will provide a (locally) optimum solution of the general nonconvex problem. The solution obtained from the proposed approach is compared to the classical block-diagonalization (BD) strategy, typically used to solve the nonconvex multiuser MIMO network by forcing no inter-user interference. Simulation results show that the proposed approach improves both the system sum rate and the power harvested by users simultaneously. In terms of computational time, the proposed DC programming outperforms the classical gradient methods.Peer ReviewedPostprint (author's final draft

Joint optimization of power and data transfer in multiuser MIMO systems

We present an approach to solve the nonconvex optimization problem that arises when designing the transmit covariance matrices in multiuser multiple-input multiple-output (MIMO) broadcast networks implementing simultaneous wireless information and power transfer (SWIPT). The MIMO SWIPT problem is formulated as a general multiobjective optimization problem, in which data rates and harvested powers are optimized simultaneously. Two different approaches are applied to reformulate the (nonconvex) multiobjective problem. In the first approach, the transmitter can control the specific amount of power to be harvested by power transfer whereas in the second approach the transmitter can only control the proportion of power to be harvested among the different harvesting users. We solve the resulting formulations using the majorization-minimization (MM) approach. The solution obtained from the MM approach is compared to the classical block-diagonalization (BD) strategy, typically used to solve the nonconvex multiuser MIMO network by forcing no interference among users. Simulation results show that the proposed approach improves over the BD approach both the system sum rate and the power harvested by users. Additionally, the computational times needed for convergence of the proposed methods are much lower than the ones required for classical gradient-based approaches.Peer ReviewedPostprint (author's final draft