Capital simbólico e investigación. Una nota sobre el capital corporal

Este trabajo tiene como propósito presentar algunos potenciales aportes de la Teoría del Campo de Pierre Bourdieu en tres niveles de lectura: El de los fenómenos a estudiar en el marco de un proyecto de investigación, el del estatuto de esta teoría dentro de la Teoría Social Contemporánea y, finalmente, el de la posición del que escribe dentro del campo de investigación. El énfasis va a ponerse en el nivel de los fenómenos que es posible reconstruir a partir del análisis de fragmentos de documentos producidos en el trabajo de campo. Finalmente se harán algunas conclusiones sobre el uso de la categoría capital corporal para designar una subespecie de capital simbólico en el dominio de las prácticas corporales parte de la intervención de la Educación Física en una cárcel de la Provincia de Buenos Aires.

Capital simbólico e investigación. Una nota sobre el capital corporal

Este trabajo tiene como propósito presentar algunos potenciales aportes de la Teoría del Campo de Pierre Bourdieu en tres niveles de lectura: El de los fenómenos a estudiar en el marco de un proyecto de investigación, el del estatuto de esta teoría dentro de la Teoría Social Contemporánea y, finalmente, el de la posición del que escribe dentro del campo de investigación. El énfasis va a ponerse en el nivel de los fenómenos que es posible reconstruir a partir del análisis de fragmentos de documentos producidos en el trabajo de campo. Finalmente se harán algunas conclusiones sobre el uso de la categoría capital corporal para designar una subespecie de capital simbólico en el dominio de las prácticas corporales parte de la intervención de la Educación Física en una cárcel de la Provincia de Buenos Aires.

Relational and Allegorical Semantics for Constraint Logic Programming

El cálculo de relaciones binarias fue creado por De Morgan en 1860 para ser posteriormente desarrollado en gran medida por Peirce y Schröder. Tarski, Givant, Freyd y Scedrov demostraron que las álgebras relacionales son capaces de formalizar la lógica de primer orden, la lógica de orden superior así como la teoría de conjuntos. A partir de los resultados matemáticos de Tarski y Freyd, esta tesis desarrolla semánticas denotacionales y operacionales para la programación lógica con restricciones usando el álgebra relacional como base. La idea principal es la utilización del concepto de semántica ejecutable, semánticas cuya característica principal es el que la ejecución es posible utilizando el razonamiento estándar del universo semántico, este caso, razonamiento ecuacional. En el caso de este trabajo, se muestra que las álgebras relacionales distributivas con un operador de punto fijo capturan toda la teoría y metateoría estándar de la programación lógica con restricciones incluyendo los árboles utilizados en la búsqueda de demostraciones. La mayor parte de técnicas de optimización de programas, evaluación parcial e interpretación abstracta pueden ser llevadas a cabo utilizando las semánticas aquí presentadas. La demostración de la corrección de la implementación resulta extremadamente sencilla. En la primera parte de la tesis, un programa lógico con restricciones es traducido a un conjunto de términos relacionales. La interpretación estándar en la teoría de conjuntos de dichas relaciones coincide con la semántica estándar para CLP. Las consultas contra el programa traducido son llevadas a cabo mediante la reescritura de relaciones. Para concluir la primera parte, se demuestra la corrección y equivalencia operacional de esta nueva semántica, así como se define un algoritmo de unificación mediante la reescritura de relaciones. La segunda parte de la tesis desarrolla una semántica para la programación lógica con restricciones usando la teoría de alegorías—versión categórica del álgebra de relaciones—de Freyd. Para ello, se definen dos nuevos conceptos de Categoría Regular de Lawvere y _-Alegoría, en las cuales es posible interpretar un programa lógico. La ventaja fundamental que el enfoque categórico aporta es la definición de una máquina categórica que mejora e sistema de reescritura presentado en la primera parte. Gracias al uso de relaciones tabulares, la máquina modela la ejecución eficiente sin salir de un marco estrictamente formal. Utilizando la reescritura de diagramas, se define un algoritmo para el cálculo de pullbacks en Categorías Regulares de Lawvere. Los dominios de las tabulaciones aportan información sobre la utilización de memoria y variable libres, mientras que el estado compartido queda capturado por los diagramas. La especificación de la máquina induce la derivación formal de un juego de instrucciones eficiente. El marco categórico aporta otras importantes ventajas, como la posibilidad de incorporar tipos de datos algebraicos, funciones y otras extensiones a Prolog, a la vez que se conserva el carácter 100% declarativo de nuestra semántica. ABSTRACT The calculus of binary relations was introduced by De Morgan in 1860, to be greatly developed by Peirce and Schröder, as well as many others in the twentieth century. Using different formulations of relational structures, Tarski, Givant, Freyd, and Scedrov have shown how relation algebras can provide a variable-free way of formalizing first order logic, higher order logic and set theory, among other formal systems. Building on those mathematical results, we develop denotational and operational semantics for Constraint Logic Programming using relation algebra. The idea of executable semantics plays a fundamental role in this work, both as a philosophical and technical foundation. We call a semantics executable when program execution can be carried out using the regular theory and tools that define the semantic universe. Throughout this work, the use of pure algebraic reasoning is the basis of denotational and operational results, eliminating all the classical non-equational meta-theory associated to traditional semantics for Logic Programming. All algebraic reasoning, including execution, is performed in an algebraic way, to the point we could state that the denotational semantics of a CLP program is directly executable. Techniques like optimization, partial evaluation and abstract interpretation find a natural place in our algebraic models. Other properties, like correctness of the implementation or program transformation are easy to check, as they are carried out using instances of the general equational theory. In the first part of the work, we translate Constraint Logic Programs to binary relations in a modified version of the distributive relation algebras used by Tarski. Execution is carried out by a rewriting system. We prove adequacy and operational equivalence of the semantics. In the second part of the work, the relation algebraic approach is improved by using allegory theory, a categorical version of the algebra of relations developed by Freyd and Scedrov. The use of allegories lifts the semantics to typed relations, which capture the number of logical variables used by a predicate or program state in a declarative way. A logic program is interpreted in a _-allegory, which is in turn generated from a new notion of Regular Lawvere Category. As in the untyped case, program translation coincides with program interpretation. Thus, we develop a categorical machine directly from the semantics. The machine is based on relation composition, with a pullback calculation algorithm at its core. The algorithm is defined with the help of a notion of diagram rewriting. In this operational interpretation, types represent information about memory allocation and the execution mechanism is more efficient, thanks to the faithful representation of shared state by categorical projections. We finish the work by illustrating how the categorical semantics allows the incorporation into Prolog of constructs typical of Functional Programming, like abstract data types, and strict and lazy functions.

Fundamental finite key limits for information reconciliation in quantum key distribution

The security of quantum key distribution protocols is guaranteed by the laws of quantum mechanics. However, a precise analysis of the security properties requires tools from both classical cryptography and information theory. Here, we employ recent results in non-asymptotic classical information theory to show that information reconciliation imposes fundamental limitations on the amount of secret key that can be extracted in the finite key regime. In particular, we find that an often used approximation for the information leakage during one-way information reconciliation is flawed and we propose an improved estimate.

Ecología política y economía de la visibilidad de los dispositivos tecnológicos de escala urbana durante el siglo XX Abriendo la caja negra

En paralelo a la superficie cotidiana de la ciudad moderna, discurre otra "ciudad invisible" o "caja negra" tecnológica, que opera, de manera silenciosa e imperceptible, al servicio de los ciudadanos. Paradójicamente, en este espacio invisible, se toman decisiones de la máxima relevancia para la ciudad: en la "caja negra", las ciudades pactan sus relaciones con la naturaleza; a través de ella, se produce la administración y distribución de los recursos que componen su metabolismo urbano. En definitiva, la "caja negra" es el conjunto de las arquitecturas donde se urbaniza la naturaleza, donde ésta pasa a ser ciudad. Y, sin embargo, ha tendido a permanecer invisible. No obstante, en el último tercio del siglo XX, se ha "abierto la caja negra" urbana y lo que era invisible ha dejado de serlo o, al menos, ha alterado su estatuto de visibilidad. El objetivo de esta tesis doctoral es evaluar las repercusiones arquitectónicas, urbanísticas y ecológicas, que conlleva este reciente fenómeno urbano que, desde hace unas décadas, está teniendo lugar en muchas de las ciudades herederas de las grandes reformas urbanas acometidas en las metrópolis europeas durante el siglo XIX, bajo el paradigma simbólico de un proyecto moderno "prometeico" y emancipador. Para abordar dicho análisis, se pondrán en relación dos parámetros urbanos elementales que han tendido a ser estudiados por separado. Por un lado, la "ecología política urbana", es decir, la red de relaciones socio-ecológicas que acontecen en la ciudad. Por otro lado, la "economía de la visibilidad", es decir, las formas de articular lo visible y lo invisible, en relación a los marcos de gobernanza. La intersección entre la "ecología política urbana" y la "economía de la visibilidad" proporciona un marco de análisis efectivo para comprender el fenómeno de la "apertura de la caja negra" y conlleva un cuestionamiento de algunas nociones dominantes en la teoría urbana y arquitectónica clásicas, como la segregación de la naturaleza, las infraestructuras y la sociedad o como las formas tradicionales de explotación ecológica del medio. Además, ofrece un criterio de análisis privilegiado para la comprensión del proceso de deslegitimación (filosófica, arquitectónica, económica, así como desde perspectivas ecológicas, sociales, de género o queer) de los modelos urbanísticos integrales modernos, herederos de los marcos antropocéntricos del siglo XIX. Por último, proporciona algunas herramientas arquitectónicas para afrontar los desafíos ecosistémicos del siglo XXI. A través del estudio de autores relevantes que han analizado esta problemática para la arquitectura, así como del estudio de casos arquitectónicos que han marcado hitos fundamentales en la consolidación urbana de los procesos asociados a la "caja negra", se concluirá que, en términos ecológicos, la ciudad moderna ha movilizado una "ecología política urbana" basada en fórmulas de sometimiento del entorno, a partir de operaciones arquitectónicas y tecnológicas invisibles. En esta tesis doctoral se estudiará la organización arquitectónica de las arquitecturas de la "caja negra" y se evaluará si el fenómeno de la "apertura de la caja negra" puede ser considerado como un síntoma de la alteración en la "ecología política urbana". 'Abriremos la caja negra" para estudiar cómo se integran en el espacio urbano los dispositivos tecnológicos de escala urbana, toda vez éstos han dejado de ser invisibles. Cómo participan, como un actor más, en la configuración de otros marcos de cohabitación, dentro de la ciudad contemporánea. ABSTRACT An 'invisible city' or technological 'black box' runs parallel to the day-to-day surface of modern cities, remaining silent, unnoticed, at the service of the citizenry. Paradoxically, this invisible space is where some of the most relevant decisions concerning the city are made: the 'black box' is where cities agree on their relationships with nature; it is used to manage and distribute the resources that form its urban metabolism. In short, the 'black box' is the collection of architectures where nature is urbanised, where it becomes a city. And in spite of all this, it has mostly remained invisible. Nevertheless, this urban 'black box' was opened during the last third of the 20th century, so what used to be invisible is invisible no more, or at least the laws governing its visibility have been altered. The purpose of this doctoral thesis is to evaluate the architectural, urban planning and ecological repercussions of this recent urban phenomenon that has been taking place for several decades in many of the cities that followed in the footsteps of the large European metropolises of the 19th century, under the symbolic paradigm of a modern 'prometheic' and emancipating project. This analysis shall be done by juxtaposing two basic urban parameters that in general have been studied separately: frstly the ‘urban political ecology', that is, the network of socio-ecological relationships within the city. Secondly, the 'economy of visibility', that is, the way the visible and invisible spheres are structured in relation with the governance frameworks. The intersection between the 'urban political ecology' and the 'economy of visibility' provides an effective analysis framework to understand the phenomenon of the 'opening of the black box'. It entails calling into question some of the predominant notions in classical urban and architectural theory, such as the segregation of nature, infrastructures and society, or the traditional forms of ecological usage of the environment. It also offers an exceptional analysis criterion to understand the discrediting process (from a philosophical, architectural, economic perspective, but also from the point of view of ecology, society, gender or queerness) of modern all-encompassing urban models that draw from the anthropocentric frameworks of the 19th century. Finally, it provides some architectural tools to tackle 21st-century ecosystemic challenges. The study of relevant authors that have analysed these problems for architecture, as well as the study of milestone architectural cases for the urban consolidation of processes associated to the 'black box', shall serve to reach the conclusion that, in ecological terms, modern cities have mobilised an 'urban political ecology' based on formulas of subjugation of the environment, through invisible architectural and technological operations. This thesis shall present an evaluation of whether the phenomenon of the 'opening of the black box' can be considered a symptom of the alteration of the 'urban political ecology'. We shall 'open the black box' to study the integration of the various urbanscale technological devices within the urban landscape, now that they have ceased to be invisible. We shall see how they participate, like any other actor, in the confguration of other cohabitation frameworks within today's cities.

Computational method to reduce the search space for directed protein evolution

We introduce a computational method to optimize the in vitro evolution of proteins. Simulating evolution with a simple model that statistically describes the fitness landscape, we find that beneficial mutations tend to occur at amino acid positions that are tolerant to substitutions, in the limit of small libraries and low mutation rates. We transform this observation into a design strategy by applying mean-field theory to a structure-based computational model to calculate each residue's structural tolerance. Thermostabilizing and activity-increasing mutations accumulated during the experimental directed evolution of subtilisin E and T4 lysozyme are strongly directed to sites identified by using this computational approach. This method can be used to predict positions where mutations are likely to lead to improvement of specific protein properties.

Quantisation of the bosonic string

In this work we review the basic principles of the theory of the relativistic bosonic string through the study of the action functionals of Nambu-Goto and Polyakov and the techniques required for their canonical, light-cone, and path-integral quantisation. For this purpose, we briefly review the main properties of the gauge symmetries and conformal field theory involved in the techniques studied.

Improved and customized secondary optics for photo-voltaic concentrators

In this contribution the line flow method is applied to an optimized secondary optics in a photovoltaic concentration system where the primary optics is already defined and characterized. This method is a particular application of photic field theory. This method uses the parameterization of a given primary optics, including actual tolerances of the manufacturing process. The design of the secondary optics is constrained by the selection of primary optics and maximizes the concentration at a previously specified collection area. The geometry of the secondary element is calculated by using a virtual source, which sends light in a first concentration step. This allows us to calculate the line flow for this specific case. This concept allows designing more compact and efficient secondary optics of photovoltaic systems.

A presença do homo academicus na contabilidade: um olhar bourdieusiano sobre o contexto social do desenvolvimento da produção científica contábil brasileira

Esta pesquisa investiga o contexto social do desenvolvimento da produção científica contábil brasileira, defendendo a tese de que os agentes, no decorrer do processo de divulgação de suas investigações, estão priorizando aspectos produtivistas e quantitativos e, consequentemente, deixando em segundo plano a preocupação qualitativa e epistemológica [vigilância crítica] de tal produção. Fundamentado na Teoria de Campos de Pierre Bourdieu, este estudo busca relacionar a socialização acadêmica, o habitus dos agentes imbricados no campo, a distribuição do capital científico na área contábil e as características epistemológicas das publicações científicas da área, para obtenção das evidências sobre a problemática levantada. Trata-se de um levantamento operacionalizado por meio de entrevista semiestruturada, com uma amostra de 9 respondentes e estudo documental, com uma amostra de 43 artigos. Os dados foram analisados com emprego da técnica de análise de conteúdo. Apoiando-se em Bourdieu (2004, 2008, 2009, 2011, 2013) foram encontradas evidências de que as teorias, conceitos, metodologias, técnicas e demais escolhas realizadas pelos pesquisadores da área contábil, na maioria das vezes, não passam de manobras estratégicas que visam conquistar, reforçar, assegurar ou derrubar o monopólio da autoridade científica, visando a obtenção de maior poder simbólico no campo. Com relação ao habitus dos agentes pertencentes ao campo científico contábil, constatou-se uma tendência ao produtivismo em consequência das determinações dos órgãos reguladores da pesquisa em contabilidade (CAPES) e das lutas simbólicas travadas no campo para obtenção da autoridade científica. No tocante à socialização acadêmica, reforçou-se a presença de condutas produtivistas, por meio dos programas de pós-graduação stricto sensu, que repassam aos agentes as regras do jogo científico, doutrinando-os na maneira de publicar grande quantidade de comunicações em pouco tempo e com menos custos. As análises epistemológicas puderam triangular os dois últimos constructos, a fim de lhes dar validade, e evidenciaram uma preferência por temáticas que envolvem a contabilidade destinada aos usuários externos e procedimentos contábeis destinados ao mercado financeiro, privilegiando a utilização de dados secundários, por meio de pesquisas documentais. Em termos metodológicos, constatou-se a presença unânime de estudos positivistas, com alguns aspectos empiristas, mostrando uma ausência de inovação em termos de pesquisas norteadas por abordagens metodológicas alternativas e utilização de modelos econométricos para explicar a realidade observada sem teoria para embasar e explicar esses modelos. Por fim, a distribuição do capital simbólico no campo, mostrou que individualmente nenhum agente desponta com maior capital científico, mas, institucionalmente, a FEA/USP ocupa essa posição de destaque. Por conseguinte, pôde-se concluir que o campo científico contábil permanece estagnado e sem grandes modificações teóricas, pelo fato do produtivismo e das lutas simbólicas no interior do campo; fatos esses que, de certa maneira, motivaram a criação de uma espécie de \"receita mágica para publicar\" ou \"formato ideal\" legitimado, institucionalizado e difícil de ser modificado, a não ser que ocorra uma revolução científica que mude o paradigma existente

Critical behavior of su(1|1) supersymmetric spin chains with long-range interactions

We introduce a general class of su(1|1) supersymmetric spin chains with long-range interactions which includes as particular cases the su(1|1) Inozemtsev (elliptic) and Haldane-Shastry chains, as well as the XX model. We show that this class of models can be fermionized with the help of the algebraic properties of the su(1|1) permutation operator and take advantage of this fact to analyze their quantum criticality when a chemical potential term is present in the Hamiltonian. We first study the low-energy excitations and the low-temperature behavior of the free energy, which coincides with that of a (1+1)-dimensional conformal field theory (CFT) with central charge c=1 when the chemical potential lies in the critical interval (0,E(π)), E(p) being the dispersion relation. We also analyze the von Neumann and Rényi ground state entanglement entropies, showing that they exhibit the logarithmic scaling with the size of the block of spins characteristic of a one-boson (1+1)-dimensional CFT. Our results thus show that the models under study are quantum critical when the chemical potential belongs to the critical interval, with central charge c=1. From the analysis of the fermion density at zero temperature, we also conclude that there is a quantum phase transition at both ends of the critical interval. This is further confirmed by the behavior of the fermion density at finite temperature, which is studied analytically (at low temperature), as well as numerically for the su(1|1) elliptic chain.

Prediction of hidden multiferroic order in graphene zigzag ribbons

An electronic phase with coexisting magnetic and ferroelectric order is predicted for graphene ribbons with zigzag edges. The electronic structure of the system is described with a mean-field Hubbard model that yields results very similar to those of density functional calculations. Without further approximations, the mean-field theory is recasted in terms of a BCS wave function for electron-hole pairs in the edge bands. The BCS coherence present in each spin channel is related to spin-resolved electric polarization. Although the total electric polarization vanishes, due to an internal phase locking of the BCS state, strong magnetoelectric effects are expected in this system. The formulation naturally accounts for the two gaps in the quasiparticle spectrun, Δ0 and Δ1, and relates them to the intraband and interband self-energies.

Transport across two interacting quantum dots: Bulk Kondo, Kondo box, and molecular regimes

We analyze the transport properties of a double quantum dot device with both dots coupled to perfect conducting leads and to a finite chain of N noninteracting sites connecting both of them. The interdot chain strongly influences the transport across the system and the local density of states of the dots. We study the case of a small number of sites, so that Kondo box effects are present, varying the coupling between the dots and the chain. For odd N and small coupling between the interdot chain and the dots, a state with two coexisting Kondo regimes develops: the bulk Kondo due to the quantum dots connected to leads and the one produced by the screening of the quantum dot spins by the spin in the finite chain at the Fermi level. As the coupling to the interdot chain increases, there is a crossover to a molecular Kondo effect, due to the screening of the molecule (formed by the finite chain and the quantum dots) spin by the leads. For even N the two Kondo temperatures regime does not develop and the physics is dominated by the usual competition between Kondo and antiferromagnetism between the quantum dots. We finally study how the transport properties are affected as N is increased. For the study we used exact multiconfigurational Lanczos calculations and finite-U slave-boson mean-field theory at T=0. The results obtained with both methods describe qualitatively and also quantitatively the same physics.

Relativistic many-body bound systems : electromagnetic properties /

Mode of access: Internet.

The dynamics of fields of higher spin /

Mode of access: Internet.

New theories in physics : proceedings of the XI Warsaw Symposium on Elementary Particle Physics, 23-27 May, 1988, Kazimierz, Poland /

Mode of access: Internet.