Motivados pelos resultados do artigo [BBFK11], nosso trabalho começa analisando, no caso da álgebra de Lie afim sl(n;C), a possibilidade de se obter módulos de Verma J-imaginários, via representações análogas às feitas por Cox em [Cox05]. Inicialmente consideramos, por simplicidade, n = 2 e, só então, analisamos o caso geral. Depois, de modo análogo, estudamos os artigos [CF04] e [CF05] com o intuito de obter módulos J-intermediários de Wakimoto. Finalmente imbutimos, no caso n = 2, uma ação de álgebra de Virasoro nos módulos imaginários de Wakimoto, utilizando-nos do resultado exposto em [EFK98], em que tal problema é abordado para o caso dos módulos de Verma. Desta forma, obtemos equações análogas às de Knizhnik-Zamolodchikov (equações KZ) para os módulos imaginários de Wakimoto. / Following the results of [BBFK11], our work starts analyzing (for bsl(n;C)) if we can obtain J-imaginary Verma modules using similar representations used by Cox in [Cox05]. We did it for n = 2 and after, for the general case. The next step was the study of J-intermediate Wakimoto modules, following the ideas of [CF04] and [CF05]. To finish, for affine sl(2;C), we defined an action of Virasoro algebra on the imaginary Wakimoto modules following [EFK98] and we obtained an analogue of the KZ-equations for imaginary Wakimoto modules.

Motivados pelos resultados do artigo [BBFK11], nosso trabalho começa analisando, no caso da álgebra de Lie afim sl(n;C), a possibilidade de se obter módulos de Verma J-imaginários, via representações análogas às feitas por Cox em [Cox05]. Inicialmente consideramos, por simplicidade, n = 2 e, só então, analisamos o caso geral. Depois, de modo análogo, estudamos os artigos [CF04] e [CF05] com o intuito de obter módulos J-intermediários de Wakimoto. Finalmente imbutimos, no caso n = 2, uma ação de álgebra de Virasoro nos módulos imaginários de Wakimoto, utilizando-nos do resultado exposto em [EFK98], em que tal problema é abordado para o caso dos módulos de Verma. Desta forma, obtemos equações análogas às de Knizhnik-Zamolodchikov (equações KZ) para os módulos imaginários de Wakimoto. / Following the results of [BBFK11], our work starts analyzing (for bsl(n;C)) if we can obtain J-imaginary Verma modules using similar representations used by Cox in [Cox05]. We did it for n = 2 and after, for the general case. The next step was the study of J-intermediate Wakimoto modules, following the ideas of [CF04] and [CF05]. To finish, for affine sl(2;C), we defined an action of Virasoro algebra on the imaginary Wakimoto modules following [EFK98] and we obtained an analogue of the KZ-equations for imaginary Wakimoto modules.

Esta dissertação oferece uma introdução às já conhecidas álgebras de Krichever-Novikov se restringindo aos exemplos abordados previamente em Bremner (1995), Cox (2013), Cox e Jurisich (2013), Cox, Futorny e Martins (2014), Bueno, Cox e Furtony (2009), e as definições de estruturas que podem auxiliar a estudar estes espaços, incluindo álgebras de Lie afins, álgebras de loop e módulos de Verma. Considerando K uma álgebra de Krichever-Novikov do tipo 4-ponto, 3-ponto, elíptica ou DJKM e suas respectivas subálgebras de Heisenberg K\' = K hK , onde hK é a subálgebra de Cartan de K , nos Teoremas 3.2.3, 3.4.3, 3.6.3 e 3.8.3 são apresentados critérios explícitos de irredutibilidade para K\'-módulos do tipo -Verma. / This work gives an introduction to the already known Krichever-Novikov algebras limited only to the examples approached before in Bremner (1995), Cox (2013), Cox e Jurisich (2013), Cox, Futorny and Martins (2014), Bueno, Cox and Furtony (2009), and the structures definitions that could help us to study these spaces, including affine Lie algebras, loop algebras and Verma modules. Let K be a 4-point, 3-point, elliptic or DJKM Krichever-Novikov algebra and its respective Heisenberg subalgebras K\' = K hK , where hK is the K Cartan subalgebra. In the Theorems 3.2.3, 3.4.3, 3.6.3 and 3.8.3 we will give a explicit irreducibility criteria for -Verma K\'-modules.

Esta dissertação oferece uma introdução às já conhecidas álgebras de Krichever-Novikov se restringindo aos exemplos abordados previamente em Bremner (1995), Cox (2013), Cox e Jurisich (2013), Cox, Futorny e Martins (2014), Bueno, Cox e Furtony (2009), e as definições de estruturas que podem auxiliar a estudar estes espaços, incluindo álgebras de Lie afins, álgebras de loop e módulos de Verma. Considerando K uma álgebra de Krichever-Novikov do tipo 4-ponto, 3-ponto, elíptica ou DJKM e suas respectivas subálgebras de Heisenberg K\' = K hK , onde hK é a subálgebra de Cartan de K , nos Teoremas 3.2.3, 3.4.3, 3.6.3 e 3.8.3 são apresentados critérios explícitos de irredutibilidade para K\'-módulos do tipo -Verma. / This work gives an introduction to the already known Krichever-Novikov algebras limited only to the examples approached before in Bremner (1995), Cox (2013), Cox e Jurisich (2013), Cox, Futorny and Martins (2014), Bueno, Cox and Furtony (2009), and the structures definitions that could help us to study these spaces, including affine Lie algebras, loop algebras and Verma modules. Let K be a 4-point, 3-point, elliptic or DJKM Krichever-Novikov algebra and its respective Heisenberg subalgebras K\' = K hK , where hK is the K Cartan subalgebra. In the Theorems 3.2.3, 3.4.3, 3.6.3 and 3.8.3 we will give a explicit irreducibility criteria for -Verma K\'-modules.

Este trabalho tem como objetivo principal estudar módulos irredutíveis sobre as álgebras de Kac-Moody afim, conforme [7]. Em particular, a técnica de localização foi aplicada aos módulos de Verma imaginários sobre a álgebra de Lie afim A(1)1, com o objetivo de obter novos módulos irredutíveis sobre essa álgebra. Conforme [8] e [6], é o mesmo que aplicar a técnica de localização à primeira realização de campos livres de A(1)1 .Para cumprir o objetivo, introduzimos as álgebras de Kac-Moody, tendo como foco principal as álgebras de Kac-Moody do tipo afim, conforme [14]. Em seguida, definimos os módulos de Verma,destacando os módulos de Verma imaginários sobre a álgebra de Lie afim A(1)1, conforme [8]. / The main purpose of this work is to study the irreducible modules of affine Kac-Moody algebras,according to [7].In particular, the localization technique was applied to the imaginary Verma modules of affine Lie algebra A(1)1, with the purpose to obtain new irreducible modules of this algebra. According to[8] and [6], it is the same as to apply the localization technique to the first realization of free fields of A(1)1.To achieve the purpose, we introduced the Kac-Moody algebras, having the main focus the af-fine Kac-Moody algebras, according to [14]. Following, we defined the Verma modules, highlighting imaginary Verma modules of affine Lie algebra A(1)1, according to [8].

Este trabalho tem como objetivo principal estudar módulos irredutíveis sobre as álgebras de Kac-Moody afim, conforme [7]. Em particular, a técnica de localização foi aplicada aos módulos de Verma imaginários sobre a álgebra de Lie afim A(1)1, com o objetivo de obter novos módulos irredutíveis sobre essa álgebra. Conforme [8] e [6], é o mesmo que aplicar a técnica de localização à primeira realização de campos livres de A(1)1 .Para cumprir o objetivo, introduzimos as álgebras de Kac-Moody, tendo como foco principal as álgebras de Kac-Moody do tipo afim, conforme [14]. Em seguida, definimos os módulos de Verma,destacando os módulos de Verma imaginários sobre a álgebra de Lie afim A(1)1, conforme [8]. / The main purpose of this work is to study the irreducible modules of affine Kac-Moody algebras,according to [7].In particular, the localization technique was applied to the imaginary Verma modules of affine Lie algebra A(1)1, with the purpose to obtain new irreducible modules of this algebra. According to[8] and [6], it is the same as to apply the localization technique to the first realization of free fields of A(1)1.To achieve the purpose, we introduced the Kac-Moody algebras, having the main focus the af-fine Kac-Moody algebras, according to [14]. Following, we defined the Verma modules, highlighting imaginary Verma modules of affine Lie algebra A(1)1, according to [8].

<p>This thesis consists of two papers on the spectral geometry of locally symmetric spaces of Riemannian and Lorentzian signature. Both works are concerned with the idea of relating analysis on such spaces to structures on their boundaries.</p><p>The first paper is motivated by a conjecture of Patterson on the Selberg zeta function of Kleinian groups. We consider geometrically finite hyperbolic cylinders with non-compact Riemann surfaces of finite area as cross sections. For these cylinders, we present a detailed investigation of the Bunke-Olbrich extension operator under the assumption that the cross section of the cylinder has one cusp. We establish the meromorphic continuation of the extension of Eisenstein series and incomplete theta series through the limit set. Furthermore, we derive explicit formulas for the residues of the extension operator in terms of boundary values of automorphic eigenfunctions.</p><p>The motivation for the second paper comes from conformal geometry in Lorentzian signature. We prove the existence and uniqueness of a sequence of differential intertwining operators for spherical principal series representations, which are realized on boundaries of anti de Sitter spaces. Algebraically, these operators correspond to homomorphisms of generalized Verma modules. We relate these families to the asymptotics of eigenfunctions on anti de Sitter spaces.</p>

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.

This thesis consists of two papers on the spectral geometry of locally symmetric spaces of Riemannian and Lorentzian signature. Both works are concerned with the idea of relating analysis on such spaces to structures on their boundaries. The first paper is motivated by a conjecture of Patterson on the Selberg zeta function of Kleinian groups. We consider geometrically finite hyperbolic cylinders with non-compact Riemann surfaces of finite area as cross sections. For these cylinders, we present a detailed investigation of the Bunke-Olbrich extension operator under the assumption that the cross section of the cylinder has one cusp. We establish the meromorphic continuation of the extension of Eisenstein series and incomplete theta series through the limit set. Furthermore, we derive explicit formulas for the residues of the extension operator in terms of boundary values of automorphic eigenfunctions. The motivation for the second paper comes from conformal geometry in Lorentzian signature. We prove the existence and uniqueness of a sequence of differential intertwining operators for spherical principal series representations, which are realized on boundaries of anti de Sitter spaces. Algebraically, these operators correspond to homomorphisms of generalized Verma modules. We relate these families to the asymptotics of eigenfunctions on anti de Sitter spaces.

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal