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Extended defects in curved spacetimesBonjour, Filipe January 1999 (has links)
This Thesis is concerned with three particular aspects of extended cosmic strings and domain walls in cosmology: their dynamics, gravitation and interaction with a black hole. In Chapter 3, we study the dynamics of an abelian-Higgs cosmic string. We find its equations of motion from an effective action and compare, for three test trajectories, the resulting motion with that observed in the Nambu-Gotō approximation. We also present a general argument showing that the corrected motion of any string is generically antirigid. We pursue the investigation of the dynamics of topological defects in Chapter 5, where we find (from integrability conditions rather than an effective action) the effective equations governing the motion of a gravitating curved domain wall. In Chapter 4 we investigate the spacetime of a gravitating domain wall in a theory with a general potential V(ɸ). We show that, depending on the gravitational coupling e of the scalar ɸ, all nontrivial solutions fall into two categories interpretable as describing respectively domain wall and false vacuum-de Sitter solutions. Wall solutions cannot exist beyond a value (^4)(_3)ɛmax, and vacuum-de Sitter solutions are unstable to decaying into wall solutions below ɛmax at ɛmax we observe a phase transition between the two types of solution. We finally specialize for the Goldstone and sine-Gordon potentials. In Chapter 6 we consider a Nielsen-Olesen vortex whose axis passes through the centre of an extremal Reissner-Nordstr0m black hole. We examine in particular the existence of piercing and expelled solutions (where the string respectively does and does not penetrate the black hole's horizon) and determine that while thin strings penetrate the horizon — and therefore can be genuinely called hair — thick strings are expelled; the two kinds of solution are separated by a phase transition.
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The Role Of Imagination In Kant' / s First CritiqueBarin, Ozlem 01 December 2003 (has links) (PDF)
The purpose of this study is to examine the role of imagination in Immanuel Kant& / #8217 / s Critique of Pure Reason by means of a detailed textual analysis and interpretation. In my systematic reading of the Kantian text, I analyse how the power of imagination comes to the foreground of Kant& / #8217 / s investigation into the transcendental conditions of knowledge. This is to explain the mediating function of imagination between the two distinct faculties of the subject / between sensibility and understanding. Imagination achieves its mediating function between sensibility and understanding through its activity of synthesis. By means of exploring the features of the activity of synthesis I attempt to display that imagination provides the ground of the unification of sensibility and understanding. The argument of this study resides in the claim that the power of imagination, through its transcendental synthesis, provides the ground of the possibility of all knowledge and experience. This is to announce imagination as the building block of Kant& / #8217 / s Copernican Revolution that grounds the objectivity of knowledge in its subjective conditions. Therefore, the goal of this study is to display imagination as a distinctive human capacity that provides the relation of our knowledge to the objects.
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Space-time channel modeling, simulation, and codingZajic, Alenka 31 July 2008 (has links)
Several emerging wireless applications require direct transmission between mobile terminals. Examples of these applications are mobile ad-hoc wireless networks, intelligent transportation systems, relay-based cellular networks, and future combat systems. Development of these mobile-to-mobile (M-to-M) systems depends on a good characterization of channel propagation. Another important consideration in modern communication systems is the use of multipath propagation to improve reliability and capacity of wireless systems. This is achieved by employing multiple antennas in multiple-input multiple-output (MIMO) systems and using techniques such as transmit and receive diversity. Considering the demand for high-speed wireless services, MIMO M-to-M systems are the leading candidates for future communication systems.
To enable the successful design of MIMO M-to-M systems, our research focuses on modeling of MIMO M-to-M multipath fading channels and on diversity techniques for MIMO systems. Specifically, we propose two-dimensional (2-D) and three-dimensional (3-D) MIMO M-to-M statistical channel models that encompass narrowband and wideband MIMO channel scenarios for macro- and micro-cell environments. Furthermore, we validate the new models against measured data and find very close agreement between them. Using our 3-D models, we also investigate different antenna array configurations and their effect on the capacity of MIMO M-to-M systems. Contrary to common assumptions, we have found that there is no significant loss of capacity if the antenna array is tilted from the horizontal plane. Finally, we propose the design criteria for space-time coded continuous phase modulated systems.
Our work would provide other researchers the tools needed to design and test future MIMO M-to-M communication systems.
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A formação continuada do professor-formador : saberes da ação docente no diálogo entre paresLauxen, Ademar Antonio January 2016 (has links)
Este estudo apresenta um processo de pesquisa-ação desenvolvido num espaço/tempo intrainstitucional, destinado para a formação permanente dos professores-formadores de um curso de licenciatura em Química, de uma universidade privada do interior do Rio Grande do Sul. Esses docentes assumiram a sua prática como parâmetro para a análise e reflexão no seu processo contínuo de formação em serviço. Este trabalho teve como objetivo analisar as concepções epistemológicas e educacionais dos professores-formadores sobre o ensinar e o aprender, visando a compreender quais racionalidades fundamentam as ações desses docentes. Ao mesmo tempo, compreender se o espaço/tempo existente contribui para que mudanças ocorram nas ações dos professores-formadores, no sentido de uma construção de processos de ensino e aprendizagem que viabilizem o desenvolvimento intelectual dos educandos e a constituição desses na dimensão crítico-reflexiva. O processo de pesquisa envolveu dez professores-formadores e o professor/pesquisador, todos integrantes do Núcleo de Educação Química (NEQ), espaço/tempo intrainstitucional constituído para que esses profissionais desenvolvam processos reflexivos, especialmente, instrumentalizando-os para uma reflexão na, sobre e após a ação. Os dados analisados resultam de um estudo, de caráter qualitativo, situado no contexto da investigação-ação, produzidos com base em entrevistas semiestruturadas, realizadas de forma individual, gravadas em áudio e, também, em encontros realizados no NEQ, com a participação de todos os pesquisados, gravados em formato audiovisual, durante o segundo semestre de 2014 A análise dos dados deu-se com base nos procedimentos da Análise Textual Discursiva (ATD). A pesquisa mostra que esse processo de interação e diálogo que se desenvolve no espaço/tempo denominado NEQ, em que os professores-formadores concretizam processos reflexivos, socializam saberes, analisam e refletem sobre as práticas pedagógicas com seus pares se constitui em prática importante para promover novos estágios de compreensão aos sujeitos-atores do processo educativo, contribuindo para a problematização de saberes e reconfiguração da ação docente. Ainda, o estudo indica que reflexões produzidas no coletivo dos professores proporcionam a constituição de um processo de permanente ressignificação do ser e fazer docente, permitindo que a discussão de questões de natureza epistemológica e pedagógica da ação, existente, tradicionalmente, em grupo restrito de educadores, aconteça com o conjunto de professores-formadores, tanto das disciplinas de características pedagógicas, quanto daquelas de conhecimento específicos da área de química Portanto, ancorando-se em teóricos como Nóvoa (1995, 2002, 2009); Zeichner (1993, 1995); Maldaner (1999, 2013); Schön (1995, 2007); Tardif (2000, 2014); Tardif e Lessard (2013); Gauthier et al. (2013) e Imbernón (2016), dentre outros, argumenta-se em favor da necessidade de espaços/tempos intrainstitucionais para a formação continuada do professor-formador na dimensão crítico-reflexiva, em todos os cursos de graduação ou áreas do saber que congregam educadores atuantes em cursos de graduação. Defende-se que o debate sobre questões de natureza epistemológicas e pedagógicas da ação docente não pode ficar atrelado à vontade de professores interessados. À medida que o educador se constitui um professor-formador, passa a ser obrigação de todos os envolvidos no curso de graduação estabelecer tal compreensão e fazê-la avançar, do contrário, não haverá mudanças significativas e não ocorrerá alteração na racionalidade que norteia a formação, em especial, dos futuros professores da educação básica. / This study presents a process of research-action developed in an intra-institutional space/time, intended for a permanent training of teacher-trainers of a Chemistry teaching degree course, of a private university in upstate Rio Grande do Sul. These teachers have taken on their practice as a parameter for the analysis and the reflection in their continuous process of training in service. This project aimed to analyze the epistemological and educational conceptions of teacher-trainers about the teaching and the learning, aiming to comprehend which rationalities base the actions of these teachers. At the same time, comprehending if the existing space/time contributes so that changes may take place in the actions of the teacher-trainers, in the sense of building teaching and learning processes that enable the intellectual development of students and their constitution in a critical and reflective dimension. The researching process involved ten teacher-trainers and the teacher/researcher, all members of the Núcleo de Educação Química (NEQ), intra-institutional space/time constituted so that these professionals may develop reflective processes, especially, instrumentalizing them for a reflection in, about and after the action. The analyzed data results from a qualitative study, situated in the context of the investigation-action, produced based on semi-structured interviews, performed individually, recorded in audio and, also, in gatherings that happened in NEQ, with the participation of all researched, recorded in audiovisual format, during the second semester of 2014. This analysis was performed based on the procedures of the Textual Discursive Analysis (TDA) This research shows that this interaction and dialogue process that is developed in the space/time called NEQ, in which the teacher-trainers concretize reflective processes, socialize knowledge, analyze and reflect about pedagogical practices with their pairs is an important practice in order to promote new stages of comprehension to the individuals-actors of the educational process, contributing to the problematization of knowledge and reconfiguration of the teaching action. Moreover, this study indicates that reflections produced among the teachers provide the constitution of a permanent process of re-signification of the teacher's being and doing, allowing the discussion of matters of epistemological and pedagogical nature of the action, existing, traditionally, in a restricted group of educators, to happen in the group of teacher-trainers, in subjects of pedagogical features, as well as those of specific knowledge in the Chemistry field. Therefore, based on theorists as Nóvoa (1995, 2002, 2009); Zeichner (1993, 1995); Maldaner (1999, 2013); Schön (1995, 2007); Tardif (2000, 2014); Tardif e Lessard (2013); Gauthier et al. (2013) e Imbernón (2016), among others, are favorable to the need of intra-institutional space/times for the continuous training of the teacher-trainer in the critical-reflective dimension, in undergraduate courses or knowledge areas that congregate acting educators in undergraduate courses. It is defended that the debate about epistemological and pedagogical matters of the teaching action cannot be linked to the will of interested teachers. As the educator becomes a teacher trainer, it becomes mandatory that all involved in the undergraduate course establish such comprehension and make it move forward, otherwise, there won't be meaningful changes and there won't be changes in the rationality that guides the training, especially, of future teachers of basic education.
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Um estudo sobre a teoria de campos no espaço-tempo não comutativo / Field theory study on the non-commutative space-timeDaniel Guimarães Tedesco 15 April 2010 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Os aspectos quânticos de teorias de campo formuladas no espaço-tempo não comutativo têm sido amplamente estudados ao longo dos anos. Um dos principais aspectos é o que na literatura ficou conhecido como mixing IR/UV. Trata-se de uma mistura das divergências, que foi vista pela primeira vez no trabalho de Minwalla et al [28], onde num estudo do campo escalar não comutativo com interação quártica vemos já a 1 loop
que o tadpole tem uma divergência UV associada a sua parte planar e, junto com ela, temos uma divergência IR associada com um gráfico não planar. Essa mistura torna a teoria não renormalizável. Dado tal problema, houve então uma busca por mecanismos que separassem essas divergências a fim de termos teorias renormalizáveis. Um mecanismo proposto foi a adição de um termo não local na ação U*(1) para que esta seja estável.Neste trabalho, estudamos através da renormalização algébrica a estabilidade deste modelo. Para tal, precisamos localizar o operador não local através de campos auxiliares
e seus respectivos ghosts (metodo de Zwanziger) na intenção de retirar os graus de liberdade indesejados que surgem. Usamos o approachda quebra soft de BRST para analisar o termo que quebra BRST, que consiste em reescrevermos tal termo com o auxílio de fontes externas que num determinado limite físico voltam ao termo original.Como resultado, vimos que a teoria com a adição deste termo na ação só é renormalizável se
tivermos que introduzir novos termos, sendo alguns deles quárticos. Porém, estes termos mudam a forma do propagador, que não desacopla as divergências. Um outro aspecto que podemos salientar é que, dependendo da escolha de alguns parâmetros, o propagador dá indícios de termos um fótonconfinante, seguindo o critério de Wilson e o critério da
perda da positividade do propagador. / The quantum aspects of field theory formulated in concommutative spacetime has been widely studied along years. A key aspect is what is known as IR/UV mixing of divergences,which was first observed by Minwalla et al [28], who studied the non-commutative scalar field with quartic interaction. In this work, at 1 loop analisys, the mixing was seen in the tadpole, which has 2 contributions: nonplanar graph carries the IR divergence and the planar graph carries the UV divergence. This fact makes the theory nonrenormalizable. Due to this problem, mechanisms have been proposed to decouple both regimes to
end up with renormalizable theories. One of these mechanisms is the addition of a nonlocal term on the U*(1) action to be stable. In this work we study, following the approach of algebraic renormalization, the stability of this model. We therefore need to localize the nonlocal operator through auxiliary fields and its ghosts (Zwanzigers method) intending to withdraw the spurious degrees of freedom. We use the soft breaking approach to analize the term that breaks the BRST symmetry rewriting it with a set of external sources in a BRST doublet in such a way that the original term is obtained when we set the sources to their physical values. As a result, we have seen that the theory with the addition of this term in the action is only renormalizable if we introduce new terms, some of them being quartic, but these terms change the form of the propagator so that they dont decouple the regimes. Another aspect that we noticed is that, depending on the choice of some parameters, the propagator gives clues of a confining photon, following the criterion of
Wilson and the criterion of loss of positivity of the propagator.
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The enigma of imaging in the Maxwell fisheye mediumSahebdivan, Sahar January 2016 (has links)
The resolution of optical instruments is normally limited by the wave nature of light. Circumventing this limit, known as the diffraction limit of imaging, is of tremendous practical importance for modern science and technology. One method, super-resolved fluorescence microscopy was distinguished with the Nobel Prize in Chemistry in 2014, but there is plenty of room for alternatives and complementary methods such as the pioneering work of Prof. J. Pendry on the perfect lens based on negative refraction that started the entire research area of metamaterials. In this thesis, we have used analytical techniques to solve several important challenges that have risen in the discussion of the microwave experimental demonstration of absolute optical instruments and the controversy surrounding perfect imaging. Attempts to overcome or circumvent Abbe's diffraction limit of optical imaging, have traditionally been greeted with controversy. In this thesis, we have investigated the role of interacting sources and detectors in perfect imaging. We have established limitations and prospects that arise from interactions and resonances inside the lens. The crucial role of detection becomes clear in Feynman's argument against the diffraction limit: “as Maxwell's electromagnetism is invariant upon time reversal, the electromagnetic wave emitted from a point source may be reversed and focused into a point with point-like precision, not limited by diffraction.” However, for this, the entire emission process must be reversed, including the source: A point drain must sit at the focal position, in place of the point source, otherwise, without getting absorbed at the detector, the focused wave will rebound and the superposition of the focusing and the rebounding wave will produce a diffraction-limited spot. The time-reversed source, the drain, is the detector which taking the image of the source. In 2011-2012, experiments with microwaves have confirmed the role of detection in perfect focusing. The emitted radiation was actively time-reversed and focused back at the point of emission, where, the time-reversed of the source sits. Absorption in the drain localizes the radiation with a precision much better than the diffraction limit. Absolute optical instruments may perform the time reversal of the field with perfectly passive materials and send the reversed wave to a different spatial position than the source. Perfect imaging with absolute optical instruments is defected by a restriction: so far it has only worked for a single–source single–drain configuration and near the resonance frequencies of the device. In chapters 6 and 7 of the thesis, we have investigated the imaging properties of mutually interacting detectors. We found that an array of detectors can image a point source with arbitrary precision. However, for this, the radiation has to be at resonance. Our analysis has become possible thanks to a theoretical model for mutually interacting sources and drains we developed after considerable work and several failed attempts. Modelling such sources and drains analytically had been a major unsolved problem, full numerical simulations have been difficult due to the large difference in the scales involved (the field localization near the sources and drains versus the wave propagation in the device). In our opinion, nobody was able to reproduce reliably the experiments, because of the numerical complexity involved. Our analytic theory draws from a simple, 1–dimensional model we developed in collaboration with Tomas Tyc (Masaryk University) and Alex Kogan (Weizmann Institute). This model was the first to explain the data of experiment, characteristic dips of the transmission of displaced drains, which establishes the grounds for the realistic super-resolution of absolute optical instruments. As the next step in Chapter 7 we developed a Lagrangian theory that agrees with the simple and successful model in 1–dimension. Inspired by the Lagrangian of the electromagnetic field interacting with a current, we have constructed a Lagrangian that has the advantage of being extendable to higher dimensions in our case two where imaging takes place. Our Lagrangian theory represents a device-independent, idealized model independent of numerical simulations. To conclude, Feynman objected to Abbe's diffraction limit, arguing that as Maxwell's electromagnetism is time-reversal invariant, the radiation from a point source may very well become focused in a point drain. Absolute optical instruments such as the Maxwell Fisheye can perform the time reversal and may image with a perfect resolution. However, the sources and drains in previous experiments were interacting with each other as if Feynman's drain would act back to the source in the past. Different ways of detection might circumvent this feature. The mutual interaction of sources and drains does ruin some of the promising features of perfect imaging. Arrays of sources are not necessarily resolved with arrays of detectors, but it also opens interesting new prospects in scanning near-fields from far–field distances. To summarise the novel idea of the thesis: • We have discovered and understood the problems with the initial experimental demonstration of the Maxwell Fisheye. • We have solved a long-standing challenge of modelling the theory for mutually interacting sources and drains. • We understand the imaging properties of the Maxwell Fisheye in the wave regime. Let us add one final thought. It has taken the scientific community a long time of investigation and discussion to understand the different ingredients of the diffraction limit. Abbe's limit was initially attributed to the optical device only. But, rather all three processes of imaging, namely illumination, transfer and detection, make an equal contribution to the total diffraction limit. Therefore, we think that for violating the diffraction limit one needs to consider all three factors together. Of course, one might circumvent the limit and achieve a better resolution by focusing on one factor, but that does not necessary imply the violation of a fundamental limit. One example is STED microscopy that focuses on the illumination, another near–field scanning microscopy that circumvents the diffraction limit by focusing on detection. Other methods and strategies in sub-wavelength imaging –negative refraction, time reversal imaging and on the case and absolute optical instruments –are concentrating on the faithful transfer of the optical information. In our opinion, the most significant, and naturally the most controversial, part of our findings in the course of this study was elucidating the role of detection. Maxwell's Fisheye transmits the optical information faithfully, but this is not enough. To have a faithful image, it is also necessary to extract the information at the destination. In our last two papers, we report our new findings of the contribution of detection. We find out in the absolute optical instruments, such as the Maxwell Fisheye, embedded sources and detectors are not independent. They are mutually interacting, and this interaction influences the imaging property of the system.
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Variáveis de contorno e loop de Wilson para uma classe de espaços-tempoSantos, Edinelson Pereira dos 25 November 2011 (has links)
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Previous issue date: 2011-11-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In thiswork,weinvestigateaclassofspace-timesbycalculatingtheloopvariables
for differentcurves,intheparticularcasewherethepathstakenareclosed(circles),we
obtain theso-calledholonomytransformations,fromwhichthetraceprovidesthematrix
obtained intheWilsonloopgravitational.Firstwediscussthecasewherethegravita-
tional fieldisgeneratedbyacylindricalshell,withoutrotation,intheapproximationof
weak field.Thenwestudythespace-timesofGödelandFriedman-Robertson-Walker.We
also investigatethespace-timesgeneratedbyacosmicstringwithinternalstructure.Fi-
nally wediscusstheKottlerspace-timeandsomemodelsofwormholes.Tocalculatethe
loop variablesweusetheperturbationexpansiontechnique,whichwecall perturbative
method, andtechniquethroughtheLorentztransformationoflocalcoordinates,which
we callthe exact method. Theobtainedresultsshowusthewaythesecontourvariables
contain informationsrelatedtothegeometricalandtopologicalpropertiesofeachoneof
these space-times. / Neste trabalho,investigamosumaclassedeespaços-tempoatravésdocálculodasva-
riáveis decontornoparadiferentescurvas,quenocasoparticular,emqueoscaminhosto-
mados sãofechados(círculos),obtêm-seasdenominadastransformaçõesdeholonomias,
do qualotraçodamatrizobtidanosforneceoloopdeWilsongravitacional.Primeiro
abordamos ocasoemqueocampogravitacionalégeradoporumacascacilíndrica,sem
rotação,naaproximaçãodecampofraco.Emseguida,estudamososespaços-tempode
Gödel eodeFriedman-Robertson-Walker.Tambéminvestigamosocenáriogeradopor
uma cordacósmicacomestruturainterna.Porfim,abordamosoespaço-tempodeKöttle
e algunsmodelosdewormholes.Paraocálculodasvariáveisdecontornoutilizamosa
técnica daexpansãoperturbativa,oqualdenominamosde método perturbativo, eatéc-
nica viatransformaçãodecoordenadasdeLorentzlocal,oqualdenominamosde método
exato. Osresultadosnosmostramdequemaneiraessasvariáveisdecontornodetectam
as característicasgeométricasetopológicasdecadaumdessesespaços-tempo.
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Um estudo sobre a teoria de campos no espaço-tempo não comutativo / Field theory study on the non-commutative space-timeDaniel Guimarães Tedesco 15 April 2010 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Os aspectos quânticos de teorias de campo formuladas no espaço-tempo não comutativo têm sido amplamente estudados ao longo dos anos. Um dos principais aspectos é o que na literatura ficou conhecido como mixing IR/UV. Trata-se de uma mistura das divergências, que foi vista pela primeira vez no trabalho de Minwalla et al [28], onde num estudo do campo escalar não comutativo com interação quártica vemos já a 1 loop
que o tadpole tem uma divergência UV associada a sua parte planar e, junto com ela, temos uma divergência IR associada com um gráfico não planar. Essa mistura torna a teoria não renormalizável. Dado tal problema, houve então uma busca por mecanismos que separassem essas divergências a fim de termos teorias renormalizáveis. Um mecanismo proposto foi a adição de um termo não local na ação U*(1) para que esta seja estável.Neste trabalho, estudamos através da renormalização algébrica a estabilidade deste modelo. Para tal, precisamos localizar o operador não local através de campos auxiliares
e seus respectivos ghosts (metodo de Zwanziger) na intenção de retirar os graus de liberdade indesejados que surgem. Usamos o approachda quebra soft de BRST para analisar o termo que quebra BRST, que consiste em reescrevermos tal termo com o auxílio de fontes externas que num determinado limite físico voltam ao termo original.Como resultado, vimos que a teoria com a adição deste termo na ação só é renormalizável se
tivermos que introduzir novos termos, sendo alguns deles quárticos. Porém, estes termos mudam a forma do propagador, que não desacopla as divergências. Um outro aspecto que podemos salientar é que, dependendo da escolha de alguns parâmetros, o propagador dá indícios de termos um fótonconfinante, seguindo o critério de Wilson e o critério da
perda da positividade do propagador. / The quantum aspects of field theory formulated in concommutative spacetime has been widely studied along years. A key aspect is what is known as IR/UV mixing of divergences,which was first observed by Minwalla et al [28], who studied the non-commutative scalar field with quartic interaction. In this work, at 1 loop analisys, the mixing was seen in the tadpole, which has 2 contributions: nonplanar graph carries the IR divergence and the planar graph carries the UV divergence. This fact makes the theory nonrenormalizable. Due to this problem, mechanisms have been proposed to decouple both regimes to
end up with renormalizable theories. One of these mechanisms is the addition of a nonlocal term on the U*(1) action to be stable. In this work we study, following the approach of algebraic renormalization, the stability of this model. We therefore need to localize the nonlocal operator through auxiliary fields and its ghosts (Zwanzigers method) intending to withdraw the spurious degrees of freedom. We use the soft breaking approach to analize the term that breaks the BRST symmetry rewriting it with a set of external sources in a BRST doublet in such a way that the original term is obtained when we set the sources to their physical values. As a result, we have seen that the theory with the addition of this term in the action is only renormalizable if we introduce new terms, some of them being quartic, but these terms change the form of the propagator so that they dont decouple the regimes. Another aspect that we noticed is that, depending on the choice of some parameters, the propagator gives clues of a confining photon, following the criterion of
Wilson and the criterion of loss of positivity of the propagator.
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A formação continuada do professor-formador : saberes da ação docente no diálogo entre paresLauxen, Ademar Antonio January 2016 (has links)
Este estudo apresenta um processo de pesquisa-ação desenvolvido num espaço/tempo intrainstitucional, destinado para a formação permanente dos professores-formadores de um curso de licenciatura em Química, de uma universidade privada do interior do Rio Grande do Sul. Esses docentes assumiram a sua prática como parâmetro para a análise e reflexão no seu processo contínuo de formação em serviço. Este trabalho teve como objetivo analisar as concepções epistemológicas e educacionais dos professores-formadores sobre o ensinar e o aprender, visando a compreender quais racionalidades fundamentam as ações desses docentes. Ao mesmo tempo, compreender se o espaço/tempo existente contribui para que mudanças ocorram nas ações dos professores-formadores, no sentido de uma construção de processos de ensino e aprendizagem que viabilizem o desenvolvimento intelectual dos educandos e a constituição desses na dimensão crítico-reflexiva. O processo de pesquisa envolveu dez professores-formadores e o professor/pesquisador, todos integrantes do Núcleo de Educação Química (NEQ), espaço/tempo intrainstitucional constituído para que esses profissionais desenvolvam processos reflexivos, especialmente, instrumentalizando-os para uma reflexão na, sobre e após a ação. Os dados analisados resultam de um estudo, de caráter qualitativo, situado no contexto da investigação-ação, produzidos com base em entrevistas semiestruturadas, realizadas de forma individual, gravadas em áudio e, também, em encontros realizados no NEQ, com a participação de todos os pesquisados, gravados em formato audiovisual, durante o segundo semestre de 2014 A análise dos dados deu-se com base nos procedimentos da Análise Textual Discursiva (ATD). A pesquisa mostra que esse processo de interação e diálogo que se desenvolve no espaço/tempo denominado NEQ, em que os professores-formadores concretizam processos reflexivos, socializam saberes, analisam e refletem sobre as práticas pedagógicas com seus pares se constitui em prática importante para promover novos estágios de compreensão aos sujeitos-atores do processo educativo, contribuindo para a problematização de saberes e reconfiguração da ação docente. Ainda, o estudo indica que reflexões produzidas no coletivo dos professores proporcionam a constituição de um processo de permanente ressignificação do ser e fazer docente, permitindo que a discussão de questões de natureza epistemológica e pedagógica da ação, existente, tradicionalmente, em grupo restrito de educadores, aconteça com o conjunto de professores-formadores, tanto das disciplinas de características pedagógicas, quanto daquelas de conhecimento específicos da área de química Portanto, ancorando-se em teóricos como Nóvoa (1995, 2002, 2009); Zeichner (1993, 1995); Maldaner (1999, 2013); Schön (1995, 2007); Tardif (2000, 2014); Tardif e Lessard (2013); Gauthier et al. (2013) e Imbernón (2016), dentre outros, argumenta-se em favor da necessidade de espaços/tempos intrainstitucionais para a formação continuada do professor-formador na dimensão crítico-reflexiva, em todos os cursos de graduação ou áreas do saber que congregam educadores atuantes em cursos de graduação. Defende-se que o debate sobre questões de natureza epistemológicas e pedagógicas da ação docente não pode ficar atrelado à vontade de professores interessados. À medida que o educador se constitui um professor-formador, passa a ser obrigação de todos os envolvidos no curso de graduação estabelecer tal compreensão e fazê-la avançar, do contrário, não haverá mudanças significativas e não ocorrerá alteração na racionalidade que norteia a formação, em especial, dos futuros professores da educação básica. / This study presents a process of research-action developed in an intra-institutional space/time, intended for a permanent training of teacher-trainers of a Chemistry teaching degree course, of a private university in upstate Rio Grande do Sul. These teachers have taken on their practice as a parameter for the analysis and the reflection in their continuous process of training in service. This project aimed to analyze the epistemological and educational conceptions of teacher-trainers about the teaching and the learning, aiming to comprehend which rationalities base the actions of these teachers. At the same time, comprehending if the existing space/time contributes so that changes may take place in the actions of the teacher-trainers, in the sense of building teaching and learning processes that enable the intellectual development of students and their constitution in a critical and reflective dimension. The researching process involved ten teacher-trainers and the teacher/researcher, all members of the Núcleo de Educação Química (NEQ), intra-institutional space/time constituted so that these professionals may develop reflective processes, especially, instrumentalizing them for a reflection in, about and after the action. The analyzed data results from a qualitative study, situated in the context of the investigation-action, produced based on semi-structured interviews, performed individually, recorded in audio and, also, in gatherings that happened in NEQ, with the participation of all researched, recorded in audiovisual format, during the second semester of 2014. This analysis was performed based on the procedures of the Textual Discursive Analysis (TDA) This research shows that this interaction and dialogue process that is developed in the space/time called NEQ, in which the teacher-trainers concretize reflective processes, socialize knowledge, analyze and reflect about pedagogical practices with their pairs is an important practice in order to promote new stages of comprehension to the individuals-actors of the educational process, contributing to the problematization of knowledge and reconfiguration of the teaching action. Moreover, this study indicates that reflections produced among the teachers provide the constitution of a permanent process of re-signification of the teacher's being and doing, allowing the discussion of matters of epistemological and pedagogical nature of the action, existing, traditionally, in a restricted group of educators, to happen in the group of teacher-trainers, in subjects of pedagogical features, as well as those of specific knowledge in the Chemistry field. Therefore, based on theorists as Nóvoa (1995, 2002, 2009); Zeichner (1993, 1995); Maldaner (1999, 2013); Schön (1995, 2007); Tardif (2000, 2014); Tardif e Lessard (2013); Gauthier et al. (2013) e Imbernón (2016), among others, are favorable to the need of intra-institutional space/times for the continuous training of the teacher-trainer in the critical-reflective dimension, in undergraduate courses or knowledge areas that congregate acting educators in undergraduate courses. It is defended that the debate about epistemological and pedagogical matters of the teaching action cannot be linked to the will of interested teachers. As the educator becomes a teacher trainer, it becomes mandatory that all involved in the undergraduate course establish such comprehension and make it move forward, otherwise, there won't be meaningful changes and there won't be changes in the rationality that guides the training, especially, of future teachers of basic education.
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Četba pro ženy v časopise Lada / Reading for women in the Lada magazineKubínová, Eva January 2018 (has links)
The diploma thesis deals with the profile of fiction published in the magazine Lada on the turn of the nineteenth century into the twentieth. The chosen representative sample of six volumes stretching over the period of twenty years was thoroughly analyzed, focusing on the most important aspects of the individual prosaic contributions, which are the following: the theme, both the main and the supporting characters, the plots, the time and space dimension of the stories, the autor's style, the tuning of proses and their belonging to different artistic movements. Another perspective of interest to this project is the author's background, its changes over time and its influence on the overall orientation and appearance of the magazine, with the overall characteristics of it also included. The deeper, intellectual background reflected in the individual proses is also discussed. Given the fact that the publishing timeline extends over two different historical epochs, this final thesis strives to find answers to the question of to which extent the author's thinking was influenced by the historically social context, i.e. to what degree the authors adopt the modern, progressive ideas of the newly shaping society of the twentieth century, and conversely, to what extent both their opinions and thinking are...
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