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1	Symplectic Structure of Constrained Systems: Gribov Ambiguity and Classical Duals for 3D Gravity Salgado Rebolledo, Patricio 28 October 2015 (has links) The present thesis is divided into two parts. Part I is devoted to the study of Gribov ambiguity in gauge systems and its relation with the appearance of degeneracies in the symplectic structure of the corresponding reduced phase space after gauge fixation. Part II is concerned with classical dual field theories for three-dimensional Einstein gravity and the symplectic structure on coadjoint orbits of the corresponding asymptotic symmetry group.In Part I, the Gribov problem is studied in the context of finite temperature QCD and the structure of the gluon propagator is analyzed. The standard confined scenario is found for low temperatures, while for high enough temperatures deconfinement takes place and a free gluon propagator is obtained. Subsequently, the relation between Gribov ambiguity and degeneracies in the symplectic structure of gauge systems is analyzed. It is shown that, in finite-dimensional systems, the presence of Gribov ambiguities in regular constrained systems always leads to a degenerate symplectic form upon Dirac reduction. The implications for the Gribov-Zwanziger approach to QCD and the symplectic structure of the theory are discussed. In Part II, geometrical actions for three-dimensional Einstein gravity are constructed by studying the symplectic structure on coadjoint orbits of the asymptotic symmetry group. The geometrical action coming from the Kirillov-Kostant symplectic form on coadjoint orbits is analyzed thought Dirac's algorithm for constrained systems. By studying the case of centrally extended groups and semi-direct products, the symplectic structure on coadjoint orbits of the Virasoro and the BMS3 group are analyzed. This allows one to associate separate geometric actions to each coadjoint orbit of the solution space, leading to two-dimensional dual fiel theories for asymptotically AdS and asymptotically flat three-dimensional gravity respectively. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished Physique théorique et mathématique Gribov Ambiguity Degenerate Systems Three-dimensional Gravity Geometrical Actions
2	Aspectos não perturbativos das teorias de Yang-Mills no calibre abeliano maximal / Non-perturbative aspects of the Yang-Mills theories in the maximal Albelian gauge Marcio André Lopes Capri 28 January 2009 (has links) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Neste tese, estudamos os efeitos não perturbativos associados à presença do horizonte de Gribov e à condensação de operadores locais de dimensão dois, numa teoria de Yang-Mills euclidiana em SU(2), quantizada no calibre abeliano maximal. Estes efeitos são introduzidos de modo a preservar as propriedades de renormalizabilidade e localidade da teoria, e refletem-se diretamente no comportamento dos propagadores. A comparação com os dados da rede indicam um bom acordo qualitativo. / In this, we study the nonperturbative effects associated to the presence of the horizon and to the condensation of local dimension two operators in an Eucledean SU(2)Yang-Mills theory quantized in the maximal Abelian gauge. Such effects are introduced in a way to preserve the properties of renormalizability and locality of the theory. The comparison with the lattice data indicates a good qualitative agreement. QCD Ambiguidades de Gribov Cópias de Gribov Região de Gribov Horizonte de Gribov Ação de Gribov-Zwanziger Função horizonte Teorias de Yang-Mills Campos de Yang-Mills Ação de Yang-Mills Calibre maximal Abeliano Regime infravermelho Regime não perturbativo Condensado(s) de dimensão dois Propagador do glúon(ghost) QCD Gribov ambiguity Gribov copies Gribov region Gribov-Zwanziger action Horizon function Yang-Mills theoris Yang-Mills fields Yang-Mills action Maximal Abelian gauge Infrared regime Nonperturbative regime Dimension two condensate(s) Gluon(ghost) propagator
3	Aspectos não perturbativos das teorias de Yang-Mills no calibre abeliano maximal / Non-perturbative aspects of the Yang-Mills theories in the maximal Albelian gauge Marcio André Lopes Capri 28 January 2009 (has links) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Neste tese, estudamos os efeitos não perturbativos associados à presença do horizonte de Gribov e à condensação de operadores locais de dimensão dois, numa teoria de Yang-Mills euclidiana em SU(2), quantizada no calibre abeliano maximal. Estes efeitos são introduzidos de modo a preservar as propriedades de renormalizabilidade e localidade da teoria, e refletem-se diretamente no comportamento dos propagadores. A comparação com os dados da rede indicam um bom acordo qualitativo. / In this, we study the nonperturbative effects associated to the presence of the horizon and to the condensation of local dimension two operators in an Eucledean SU(2)Yang-Mills theory quantized in the maximal Abelian gauge. Such effects are introduced in a way to preserve the properties of renormalizability and locality of the theory. The comparison with the lattice data indicates a good qualitative agreement. QCD Ambiguidades de Gribov Cópias de Gribov Região de Gribov Horizonte de Gribov Ação de Gribov-Zwanziger Função horizonte Teorias de Yang-Mills Campos de Yang-Mills Ação de Yang-Mills Calibre maximal Abeliano Regime infravermelho Regime não perturbativo Condensado(s) de dimensão dois Propagador do glúon(ghost) QCD Gribov ambiguity Gribov copies Gribov region Gribov-Zwanziger action Horizon function Yang-Mills theoris Yang-Mills fields Yang-Mills action Maximal Abelian gauge Infrared regime Nonperturbative regime Dimension two condensate(s) Gluon(ghost) propagator

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