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Etude et mise au point d'une nouvelle famille d'alterno-démarreur pour véhicules hybrides et électriques / Study and development of a new family of stater-generator for hybrid and electric vehiclesLi, Li 19 May 2011 (has links)
Les travaux de cette thèse portent sur une nouvelle structure de machine à double excitation (MSDE) pour l'application des véhicules hybrides et électriques. Ce type de machine, ayant deux sources d'excitation, bénéficie un degré de liberté supplémentaire et un contrôle facile sur le flux. Grâce à ce degré de liberté, la machine peut être dimensionnée de manière que son meilleur rendement coïncide avec la zone de fonctionnement la plus sollicitée de la machine. Cette nouvelle structure a fait l'objet principal de ce mémoire. Le fonctionnement de la MSDE est présenté dans les deux premiers chapitres. La machine est dimensionnée suivant un cahier des charges pour véhicule hybride. La validation expérimentale a confirmé le bon fonctionnement de la structure et montré son intérêt. Une autre problématique dans le dimensionnement de la machine est l'aspect thermique car les machines sont devenues de plus en plus compactes et puissantes. Une estimation correcte des pertes est indispensable pour évaluer correctement les performances de la machine. C'est la raison pour laquelle on a décidé de consacrer une partie de cette thèse à la modélisation des pertes fer, dont l'estimation n'est pas évidente. / The PhD work deals with a new structure of hybrid excited synchronous machine (MSDE) for the application of hybrid and electric vehicles. This kind of machine, with two excitation sources, benefits an additional degree of freedom and an easy control of flux. Due to this degree of freedom, the machine can be designed in the way that its best efficiency coincide with the most solicited operating zone. This new machine structure is the main subject of this study. The principle of this MSDE is presented in the first two chapters. The machine is then designed according to the specifications for an hybrid vehicle. The experimental validation has confirmed the proper functioning of the structure and shown its interest. Another important subject in the machine sizing is the thermal aspect because our machines are becoming more and more compact and powerful. A correct estimation of the iron loss is essential for evaluating correctly the machine performances. That's why we have decided to dedicate a part of this study to the modeling of iron loss, of which the estimation is not evident.
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Contribution à la modélisation du champ électromagnétique dans les dispositifs basses fréquences par la méthode des moments / Contribution to the modeling of the electromagnetic field in the low frequency devices by the method of momentsOubaid, Rania 16 December 2014 (has links)
La modélisation numérique est devenue incontournable dans le monde de la conception industrielle et de la recherche scientifique. Les problèmes à résoudre étant de plus en plus complexes, il est nécessaire d'adopter une approche adaptée au problème traité. Dans les domaines d'application de l'électromagnétisme basses fréquences, la méthode des éléments finis (MEF) est la méthode de référence. Actuellement, de plus en plus de dispositifs ouverts comportant de grands entrefers sont développés. Dans ce genre de problèmes, la MEF n'est pas optimale car elle nécessite de mailler un grand volume d'air pour obtenir une bonne précision. Dans cette thèse nous étudions, au travers de deux applications (représentant respectivement un système ouvert et un système à grands entrefers) une méthode alternative qui ne souffre pas des limitations évoquées : la méthode des moments (MoM) de type intégrale volumique. En effet, cette méthode nécessite de mailler uniquement les milieux magnétiques. Le principe de cette méthode est d'abord de calculer l'aimantation induite dans le milieu linéaire ou non linéaire placé sous l'effet d'un champ extérieur. Pour cela, le milieu magnétique est discrétisé en éléments hexaédriques. Dans chaque élément est localisée une aimantation considérée comme uniforme. Ensuite, la connaissance de cette aimantation induite permet de déterminer le champ magnétique en tout point de l'espace: interne, proche ou lointain. Dans un premier temps, un code basé sur la MoM a été développé pour la première application. Il permet de calculer le champ magnétostatique proche ou lointain d'une antenne basse fréquence. Une méthode permettant de calculer l'énergie magnétostatique contenue dans tout l'espace a été également mise au point. Dans deuxième temps, afin de pouvoir traiter une géométrie complexe, des modifications ont été intégrées au code afin de modéliser la deuxième application : le dispositif de test des propulseurs à effet Hall (PPS-Flex). Il s'agit de prendre en compte des symétries géométriques et physiques caractéristiques de ce dispositif. Les résultats montrent que la MoM permet de calculer le champ magnétique à l'intérieur de son canal et éventuellement au-delà. Dans les deux exemples étudiés, la méthode des moments a donné des résultats satisfaisants lors de la comparaison avec la méthode des éléments finis 3D et avec les résultats de mesures. Ces résultats montrent des gains potentiellement significatifs sur le plan des temps de calculs. A l'issu de cette thèse, nous disposons d'un outil de laboratoire permettant de modéliser le comportement du champ magnétostatique dans des systèmes ouverts et/ou à grands entrefers. / The numerical modeling has become essential in the world of industrial design and scientific research. The problems to be solved are increasingly complex making it necessary to adopt an appropriate approach for the problem addressed. In the domains of application of low frequency electromagnetic, the finite element method (FEM) is the reference method. Currently, more and more devices having large open gaps are developed. In this kind of problems, the MEF is not optimal as it requires to mesh a large volume of air to get a good accuracy. In this thesis we study, through two applications (an open system and a large gap system), an alternative method that does not suffer from the limitations discussed: the method of moments (MoM) of volume integral type. Indeed, this method requires to mesh only the magnetic media. The principle of this method is first to calculate the induced magnetization in the linear or nonlinear medium under the effect of an external field. To accomplish this, the magnetic medium is discretized into hexahedral elements. In each element, a uniform magnetization is localized. Then, the determination of this induced magnetization allows to compute the magnetic field at any point in the space: internal, near or far. In the first step, a code based on the MoM has been developed for the first application. It allows to calculate the magnetostatic field near or far from a low-frequency antenna. A method to calculate the magnetostatic energy in the whole space was also developed. Meanwhile, in the second step, in order to treat complex geometry, some modifications have been integrated into the code to model the second application: the test device of Hall effect thrusters (PPS-Flex). It consists in taking into account the physical characteristics and geometric symmetry of the device. The results show that MoM allows to calculate the magnetic field inside the channel and possibly beyond. In both examples studied, the MoM has given satisfactory results when compared with the 3D finite element method and with the results of measurements. These results show potentially significant gains in the computation time. At the end of this thesis, we have developed a laboratory tool allowing to model the behavior of the static magnetic field in open and/or wide-gap systems.
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Réactions autocatalytiques hétérogènes : vers le dimensionnement des réacteurs industriels de dissolution du dioxyde d’uranium / Autocatalysis and heterogeneous reactions : A first step towards the design of industrial reactors for uranium dissolution in nitric mediaCharlier, Florence 10 November 2017 (has links)
La dissolution du dioxyde d’uranium en milieu nitrique est une étape clef du traitement des combustibles nucléaires usés. Elle précède en effet le procédé PUREX, qui permet l’extraction liquide - liquide des radionucléides valorisables. Cette dissolution est triphasique et autocatalytique, ce qui fait que de nombreux phénomènes impactent la réaction. Une bonne compréhension de ces phénomènes, autant à l’échelle microscopique que macroscopique, est nécessaire pour pouvoir proposer un modèle de la vitesse de disparition du solide au sein des dissolveurs. Les paramètres cinétiques de la réaction de dissolution ont été déterminés, en intégrant son aspect autocatalytique. L’étude cinétique a été réalisée en suivant la dissolution par microscopie optique. Cette technique d’analyse permet une approche uni-particulaire, qui est nécessaire car elle permet de limiter l’accumulation de l’espèce autocatalytique à l’interface solide – liquide. De plus, la dissolution du dioxyde d’uranium produit des oxydes d’azote. Une réaction volumique entre ces gaz et le catalyseur a été mise en évidence. Les cinétiques de cette réaction ont été estimées à partir des résultats expérimentaux. L’importance de la prise en compte des échanges à l’interface gaz – liquide pour définir la concentration de catalyseur en solution a été démontrée. Un modèle a été réalisé sur Matlab pour permettre de discriminer l’influence de ces différents éléments. Ce modèle donne des résultats cohérents avec l’expérimental, aussi bien à l’échelle microscopique que macroscopique. Plusieurs nombres adimensionnels ont également été mis en évidence pour cerner les phénomènes dont l’impact est prépondérant, en fonction de la géométrie et de l’hydrodynamique du dissolveur. Ce modèle a permis de cerner quelques pistes d’optimisation de procédés mettant en jeux des réactions autocatalytiques. Notamment, le fait que pour ces réactions particulières, les échanges aux interfaces solide - liquide et liquide - gaz peuvent être utilisés comme leviers pour maitriser la vitesse de disparition du solide / Recycling of nuclear fuel is based on liquid – liquid extraction. The dissolution of uranium dioxide in nitric medium is hence a key step at the head - end of the entire process. This particular dissolution is triphasic and autocatalytic, which means that numerous phenomena must be taken into account. A complete understanding of these phenomena, at macroscopic and microscopic scale, is necessary in order to model the solid disappearance rate in dissolvers. The kinetical parameters of the reaction were determined for both the catalyzed and non-catalyzed reactions. The kinetic study was realized thanks to a single particle approach. The reaction rates were measured by optical microscopy. This analytical technic enables to limit the catalyst accumulation at the solid - liquid interface. Moreover, nitrous oxides are products of the uranium dioxide dissolution. Evidence of a volumic reaction between these gases and the catalyst were found, and the kinetics of this reaction was estimated from the experimental results. Gas – liquid exchanges were shown to have an important impact on the catalyst concentration in the reactor. A model was realized thanks to the software Matlab to simulate these different phenomena. It was shown to be in good agreement with experimental results, at the microscopic and macroscopic scale. Dimensionless numbers were highlighted to describe the impact of each phenomenon on the solid disappearance, including the influence of the geometry and hydrodynamics of the reactor. Finally, ways of process optimization for autocatalytic reactions were determined thanks to the model. For instance, gas – liquid and solid – liquid exchanges were shown to be an interesting lever to fix the catalyst concentration in the reactor and at the solid surface
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Teoria escalar-tensorial: Uma abordagem geométricaAlmeida, Tony Silva 29 July 2014 (has links)
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Previous issue date: 2014-07-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In this cool thesis, we consider an approach to Brans-Dicke theory of gravity in which the
scalar eld has a geometrical nature. By postulating the Palatini variation, we nd out
that the role played by the scalar eld consists in turning the space-time geometry into a
Weyl integrable manifold. This procedure leads to a scalar-tensor theory that di ers from
the original Brans-Dicke theory in many aspects and presents some new features. We
also consider the Weyl integrable geometry to investigate gravity in (2+1)-dimensions.
We show that, in addition to leading to a Newtonian limit, WIST in (2+1) dimensions
presents some interesting properties that are not shared by Einstein theory, such as geodesic
deviation between particles in a dust distribution. Finally, taking advantage of the
duality between the geometrical scalar-tensor theory and general relativity coupled with
a massless scalar eld we study naked singularities and wormholes. / Esta tese trata de tópicos relacionados às teorias escalares-tensoriais e a geometria de
Weyl integrável. Nossa abordagem será no sentido de indicar a geometria de Weyl integr
ável como sendo um ambiente natural para a introdução de teorias escalares-tensorias.
Nossa discussão será em torno da teoria de Brans-Dicke, considerada o protótipo das teorias
escalares tensoriais, no entanto a discussão é facilmente estendida para essas versões
mais gerais. Fazemos isso em dois momentos. Primeiro, indicando, no âmbito da teoria
de Brans-Dicke, que na estrutura geométrica e de campos adotadas pela teoria existe
uma relação estreita com a geometria de Weyl, inclusive associando o efeito descrito na
literatura como "quinta força"(que violaria o princípio de equivalência) com o movimento
geodésico da geometria de Weyl integrável, reformulando o postulado geodésico. E, num
segundo momento, usando o método variacional de Palatini, acabamos por formular uma
nova teoria escalar-tensorial, agora com ingredientes completamente geométricos, ambientada
numa geometria de Weyl integrável. Estudamos ainda soluções no vazio do problema
estático de uma distribuição de massa esfericamente simétrica, onde surgem objetos de
interesse astrofísico como singularidades nuas e buracos de minhoca. Também formulamos
a teoria conhecida por WIST (Weyl Integrable Spacetimes) em (2 + 1)D, o que resulta
numa teoria consistente, não sofrendo das falhas associadas à teoria da relatividade geral
nessa dimensionalidade
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Modelos cosmológicos numa teoria geométrica escalar - tensorial da gravitação: aspectos clássicos e quânticosAlves Júnior, Francisco Artur Pinheiro 27 September 2016 (has links)
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Previous issue date: 2016-09-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In this thesis, we deal with a particular geometric scalar tensor theory, which is a version of
the Brans-Dicke gravitation, formulated in aWeyl integrable space-time. This formulation
is done using the Palatini's variation procedure. The main point of our work is to perform
two particular applications of the geometrical Brans-Dicke theory. The rst one is the
study of geometric fase transition phenomena, that's related to a continuous change in
the space-time structure of the universe from a Riemann's geometry to a Weyl's geometry,
or in the inverse sense, from Weyl's geometry to Riemann's geometry. This phenomena
seems to take place when the universe starts to expand in a accelerated rate. The second
one is the investigation of classical and quantum behaviour of a anisotropic n-dimensional
universe . To nd solutions that display the dynamical compacti cation of non observed
extra dimensions is the main motivation to study such universe. / Nesta tese, reapresentamos uma teoria escalar tensorial geométrica, que é uma versão da
gravitação de Brans-Dicke formulada em um espaço-tempo de Weyl integrável. Com esta
teoria fazemos duas aplicações especí cas. Uma delas para o estudo de um fenômeno,
que chamamos de transição de fase geométrica, uma mudança contínua na estrutura geom
étrica do espaço-tempo. Este fenômeno parece ocorrer quando o universo se expande
aceleradamente. A segunda aplicação reside no estudo clássico e quântico do comportamento
de um modelo de universo n-dimensional anisotrópico. A motivação para esta
investigação é a busca de soluções que exibem o compactação dinâmica das dimensões
extras, que não são observadas.
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Análise do movimento quântico de partículas relativísticas sob ação de potenciais vetoriais e escalaresMedeiros, Eduardo Rafael Figueiredo 15 April 2010 (has links)
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Previous issue date: 2010-04-15 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / It is presented a review on three subjects: the origin and nature of topological defects, the
non-relativistic and relativistic quantum mechanics, and the gravitational and eletrostatic selfforces
that emerge from a conical spacetime surrounding a cosmic string. After setting up
this theoretical framework, it is studied the behavior of a charged particle in the presence of a
cosmic string, parallel to an uniform, constant magnetic field, which may be used as a model to
a primordial large-scale magnetic field that permeates the universe. The geometry of a negative
disclination is taken into account, this being a typically condensed matter physics topological
defect equivalent to a cosmic string, where a wedge of material is inserted into the lattice. We
computed exactly, the topological and electrostatic influences on the particles energy spectrum,
and the phase shift for the charged scalar particle scattered states. Switching to a flat-spacetime
context, spherically symmetric systems were studied, solving exactly, Klein-Gordon and Dirac
equations which describe a scalar particle subject to a Coulomb vector potential and scalar
central potentials. / Apresentamos uma revisão sobre a origem e a natureza dos defeitos topológicos, que surgem
a partir de transições de fase que podem ter ocorrido no início do processo de formação do
universo; sobre a mecânica quântica não-relativística e relativística; e sobre as auto-forças gravitacional
e eletrostática que emergem da topologia cônica do espaço-tempo gerado pela corda
cósmica. Utilizando estas ferramentas, estudamos o movimento de uma partícula carregada
na presença de uma corda cósmica, paralela a um campo magnético uniforme, de magnitude
constante, que poderia servir de modelo para um campo magnético primordial. Também consideramos
a geometria anti-cônica de uma desclinação negativa, defeito topológico análogo
à corda cósmica estudado em matéria condensada. Calculamos, exatamente, a influência da
topologia e do campo magnético no espectro de energia da partícula e encontramos o ângulo
de mudança de fase para seus estados espalhados. No espaço-tempo plano, estudamos sistemas
com simetria esférica e investigamos a dinâmica de uma partícula escalar, resolvendo,
exatamente, as equações de Klein-Gordon e Dirac, considerando potenciais centrais.
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Desenvolvimento de um modelo lagrangiano para estimar a dispersão de escalares passivos em condições de meandro do vento horizontal / Development of a lagrangian model to estimate the passive scalar dispersion in low-wind meandering conditionsStefanello, Michel Baptistella 24 February 2017 (has links)
The description of the effects of the wind meandering in the scalar dispersion is a challenging
task, since this type of flow represents a physical state characterized by multiple
scales. In this study, a Lagrangian stochastic diffusion model is derived to describe the
scalar transport during the horizontal wind meandering phenomenon, occurring in a PBL.
The model is derived from the linearization of the Langevin equation and employs a heuristic
functional form, which represents the autocorrelation functions of the meandering. The
new solutions, which describe the longitudinal and lateral wind components, were used to
simulate two experiments of contaminants dispersion in low-wind conditions, INEL (USA)
and GRAZ (Austria). The results of the comparison indicate that the new model reproduces
fairly well the observed concentrations of contaminants and, therefore, satisfactorily describes
the enhanced dispersion due to the presence of meandering. / Descrever os efeitos provocados pelo meandro do vento na dispersão de escalares é uma
tarefa desafiadora, uma vez que este tipo de escoamento representa um estado físico
caracterizado por múltiplas escalas. Neste trabalho, deriva-se um modelo estocátisco Lagrangiano
para descrever a dispersão de escalares, na camada limite planetária, durante o
fenômeno de meandro do vento horizontal. O modelo é derivado a partir da linearização da
equação de Langevin e emprega uma forma funcional heurística, que representa as funções
de autocorrelação do meandro. As novas soluções, que descrevem as componentes
longitudinais e laterais do vento, foram empregadas para simular dois experimentos de dispersão
de contaminantes em condições de vento fraco, INEL (USA) e GRAZ (Áustria). Os
resultados das comparações indicam que o novo modelo pode ser usado para reproduzir
as concentrações observadas de contaminantes e, portanto descreve de forma satisfatória
a difusão reforçada provocada pelo meandro do vento.
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A mistura dos bósons Z − Z′ e a quebra explícita da simetria leptônica no modelo 331 com neutrinos de m ao direitaDiniz Filho, Hermes Mangueira 02 October 2009 (has links)
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Previous issue date: 2009-10-02 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In this thesis, we develop some phenomenological aspects of a model based on
the gauge symmetry SU(3)CNSU(3)LNU(1)N (311νR), that include righthanded
neurinos in its matter content. We establish all the necessary structure for
the study of the phenomenological aspects of the model. First, we obtain bounds on
the angle that mix the gauge bosons Z and Z′, taking into account a requirement
of the model, namely, that the number of fermionic families is exactly three. Also we
implement the mass for both species of neutrinos (left-hand and right-handed) via
type II seesaw mechanism, obtained adding to the model a sextet of scalars which
will be responsible by the violation of the lepton number. The main consequence
is the rising of a sterile neutrino with mass in the KeV range, satisfying all the
cosmological and astrophysical constraints. This neutrino will a viable candidate
for warm dark matter in the universe. / Nesta tese, desenvolvemos alguns aspectos relacionados `a fenomenologia de
um modelo com simetria de gauge SU(3)CNSU(3)LNU(1)N (331νR), que
possui neutrinos de m ao direita no seu conte´udo de mat´eria. Estabelecemos toda
a estrutura necess´aria para o estudo dos aspectos fenomenol´ogicos do modelo. Primeiro,
vamos obter v´ınculos no angulo que mistura os b´osons de gauge Z e Z′,
levando em conta uma exig encia imposta pelo modelo, ou seja, que o n´umero de
fam´ılias fermi onicas ´e exatamente tr es. Tamb´em implementamos termos de massa
para ambas as esp´ecies de neutrinos (m ao esquerda e m ao dieita) via mecanismo
seesaw tipo II, obtido adicionado ao modelo um sexteto de escalares, que ser´a respons
´avel pela viola¸c ao do n´umero lept onico. A principal consequ encia ´e o surgimento
de um neutrino est´eril com massa na escala de KeV , satisfazendo todas as restri¸c oes
cosmol´ogicas e astrof´ısicas. Esse neutrino ser´a um vi´avel candidato `a mat´eria escura
morna do universo.
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Estudos relativos à influência de campos gravitacionais de buracos negros sobre sistemas quânticosVieira, Horácio Santana 28 February 2014 (has links)
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Previous issue date: 2014-02-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In this dissertation we consider the influence of gravitational fields due to the
black holes of Kerr-Newman and Kerr-Newman-de Sitter, on a massive scalar field,
with and without charge. We obtain the exact solutions of the radial Klein-Gordon
equation in the spacetime of Kerr-Newman which are given in terms of the confluent
Heun functions. In the particular case of a extreme Kerr-Newman black hole, the
solution is given in terms of double confluent Heun functions. We also investigate
the solutions close to the exterior event horizon and very far from the black hole.
For a charged scalar field, we obtain exact solutions corresponding to the
angular Klein-Gordon equation in the Kerr-Newman-de Sitter spacetime which are
given in terms of the Heun functions. Using a method due to Damour and Ruffini,
we study the Hawking radiation of massive scalar particles.
In the Kerr-Newman black hole, we obtain the exact solutions for both the
angular and radial Klein-Gordon equations, which are given in terms of the confluent
Heun functions. From the radial solution, we obtain the exact wave solutions near to
the exterior horizon of the black hole, and discuss the Hawking radiation of charged
massive scalar particles. / Nesta dissertação tratamos da influência do campo gravitacional produzido
pelos buracos negros de Kerr-Newman e Kerr-Newman-de Sitter sobre um campo
escalar massivo com e sem carga. Obtemos as soluções exatas da parte radial da
equação de Klein-Gordon em um espaço-tempo de Kerr-Newman, que são dadas
em termos das funções confluentes de Heun. No caso particular correspondente ao
buraco negro de Kerr-Newman extremo, a solução é dada em termos das funções
duplamente confluentes de Heun. Investigamos, também, as soluções nas proximidades
do horizonte de evento exterior e longe do buraco negro.
Para um campo escalar massivo carregado, obtemos as soluções exatas para a
parte angular da equação de Klein-Gordon em um espaço-tempo de Kerr-Newman-de
Sitter, que são dadas em temos das funções de Heun. Utilizando o método de Damour
& Ruffini, estudamos a radiação Hawking para partículas escalares massivas.
No buraco negro de Kerr-Newman, obtemos as soluções exatas de ambas
as partes radial e angular da equação de Klein-Gordon, que são dadas em termos
das funções confluentes de Heun. A partir da solução radial, obtemos as soluções de
ondas exatas próximas ao horizonte exterior do buraco negro e discutimos a radiação
Hawking para partículas escalares massivas carregadas.
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Tópicos em defeitos deformados e o movimento BrownianoSantos, Joao Rafael Lucio dos 20 November 2013 (has links)
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Previous issue date: 2013-11-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The non-linear science is a central topic covering several investigation areas, such as
biology, chemistry, mathematics and physics. In the first part of this thesis, we studied
the non-linearity in the scope of classical field theory. The discussions are based on static
solutions in (1, 1) space-time dimensions, and they are focused on kinks and lumps defects.
In the related procedures, we show several techniques which allowed us to determine new
models with their respective analytical solutions. The main mathematical tool to obtain
these results is the so called deformation method, which was also an essential piece in
the construction of a new extension method. This method presents the determination of
new two scalar fields models from the coupling between two one scalar field systems. The
method was analyzed carefully, as well as the linear stability, the zero modes, the total
energy and the superpotentials, related with the new families of potentials. Furthermore,
in the second part we presented the basics concepts about the Brownian Motion, where
we analised the features of the solution of the Langevin Equation, and we also introduced
a path integral approach to this problem in a quantum field theory way. / A ciência não-linear é tema central de diversas linhas de investigação, cobrindo áreas
como a biologia, a física, a matemática e a química. Nossa primeira vertente de trabalho
nesta tese, consiste no estudo de não-linearidades via abordagem de teoria clássica de
campos. As discussões estão baseadas em soluções estáticas em (1, 1) dimensões, com
destaque para o chamados defeitos tipo kink e lump. Nos procedimentos relatados, discorremos
a respeito de diversas técnicas para a determinação de novos modelos com suas
respectivas soluções analíticas. Um ferramental fundamental para a obtenção desses resultados
é o chamado método de deformação, o qual também foi parte essencial para a
criação de um método de extensão de modelos, onde visamos a construção de modelos de
dois campos reais a partir do acoplamento entre dois modelos de um campo. Tal método
também foi exposto em detalhes, bem como as análises sobre estabilidade linear, cálculo
de modos zeros, determinação da energia total e dos superpotenciais, relativos às novas
famílias de potenciais. Já a segunda linha de pesquisa, refere-se aos conceitos básicos do
movimento browniano, onde analisamos as propriedades da solução da equação de Langevin,
e na introdução de uma abordagem via integrais de trajetória para descrevê-lo nos
moldes de teoria de quântica de campos.
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