In this thesis we study topology of symplectic fillings of contact manifolds supported by planar open books. We obtain results regarding geography of the symplectic fillings of these contact manifolds. Specifically, we prove that if a contact manifold (M,ξ) is supported by a planar open book, then Euler characteristic and signature of any Stein filling of (M,ξ) is bounded. We also prove a similar finiteness result for contact manifolds supported by spinal open books with planar pages. Moving beyond the geography of Stein fillings, we classify fillings of some lens spaces. In addition, we classify Stein fillings of an infinite family of contact 3-manifolds up to diffeomorphism. Some contact 3-manifolds in this family can be obtained by Legendrian surgeries on (S³, ξ std) along certain Legendrian 2-bridge knots. We also classify Stein fillings, up to symplectic deformation, of an infinite family of contact 3-manifolds which can be obtained by Legendrian surgeries on (S³, ξ std) along certain Legendrian twist knots. As a corollary, we obtain a classification of Stein fillings of an infinite family of contact hyperbolic 3-manifolds up to symplectic deformation.

A contact structure is a maximally non-integrable hyperplane field $\xi$ on an odd-dimensional manifold $M$. In $3$-dimensional contact geometry, there is a fundamental dichotomy, where a contact structure is either tight or overtwisted. Making use of Giroux's correspondence between contact structures and open books for $3$-dimensional manifolds, Honda, Kazez, and Mat\'{i}c proved that verifying whether a mapping class is right-veering or not gives a way of detecting tightness of the compatible contact structure. As a counter-part to right-veering mapping classes, right-veering closed braids have been studied by Baldwin and others. Ito and Kawamuro have shown how various results on open books can be translated to results on closed braids; introducing the notion of quasi right-veering closed braids to provide a sufficient condition which guarantees tightness. We use the related concept of $P$-bigon right-veeringness for closed braids to show that given a $3$-dimensional contact manifold $(M, \xi)$ supported by an open book $(S, \phi)$, if $L \subset (M, \xi)$ is a non-$P$-bigon right-veering transverse link in pure braid position with respect to $(S, \phi)$, performing $0$-surgery along $L$ produces an overtwisted contact manifold $(M', \xi')$. Furthermore, if we suppose $L \subset (M, \xi)$ is a pure and non-quasi right-veering braid with respect to $(S, \phi)$, performing $p$-surgery along $L$, for $p \geq 0$, gives rise to an open book $(S', \phi')$ which supports an overtwisted contact manifold $(M', \xi')$.

In this thesis, we study the classification problem of Stein fillable tight contact structures on any Seifert fibered 3&minus / manifold M over S 2 with 4 singular fibers. In the case e0(M) &middot / &minus / 4 we have a complete classification. In the case e0(M) &cedil / 0 we have obtained upper and lower bounds for the number of Stein fillable contact structures on M.

[pt] Nesse trabalho apresentamos os nós legendreanos numa variedade M de dimensão 3 destacando as estruturas de contato canõnicas em R3 e T3. Para o primeiro caso estudamos os invariantes clássicos: Números de Thurston-Bennequin e Maslov. No segundo caso o número de Maslov é facilmente estendido para esse contexto, mas para o número de Thurston-Bennequin existe uma dificuldade em defini-lo, pois T3 não é simplesmente conexo. Apresentamos uma definição desse invariante para os nós lineares legendreanos em T3, seguindo um trabalho de Y. Kanda / [en] In this work we study legendrian knots in a 3-manifold M, with emphasis on the canonical contact structures in R3 and T3. For the first case we will study the classic invariants: of Thurston-Bennequin and Maslov numbers. The Maslov number is easily extended to T3, but it is difficult to define the Thurston-Bennequin number, because T3 is not simply connected. We present a definition of that invariant for the linear legendrian knots in T3 following a paper of Y. Kanda.

The problem of classifying the Anosov systems is of great interest in the theory of dynamical systems. The most important known examples are of algebraic nature and it has been conjectured on 1960s by S. Smale (SMALE, 1967) that these are in fact the only examples. This conjecture has been proved false for Anosov flows, where counter examples had been constructed for odd dimensional manifolds ((HANDEL; THURSTON, 1980) and (BARTHELMé et al., )). This non algebraic examples however are very pathological, and with some stronger hypothesis, for example, smoothness of the invariant bundles, the conjecture remains open. In 1992, it was published a paper (BENOIST; FOULON; LABOURIE, 1992) which proved that contact Anosov flows with smooth invariant bundles are in fact algebraic. In this monograph we seek to generalize the result obtained in (BENOIST; FOULON; LABOURIE, 1992). For this end, we create an adequate definition for contact Anosov Rk-actions, and following the proof strategy used in (BENOIST; FOULON; LABOURIE, 1992) we obtained a partial generalization of this result. / O problema da classificação dos sistemas Anosov são de grande interesse dentro da teoria dos sistemas dinâmicos. Os principais exemplos conhecidos são de natureza algébrica e foi levantada na década de 1960 a conjectura de que estes são os únicos exemplos (SMALE, 1967). Esta conjectura se mostrou falsa para fluxos Anosov (ações de R), onde foram construídos contraexemplos em variedades de dimensões impares ((HANDEL; THURSTON, 1980) e (BARTHELMé et al., )). Estes contra exemplos no entanto são de natureza patológica, e sob hipóteses um pouco mais fortes, por exemplo, suavidade dos fibrados invariantes, a conjectura permanece em aberto. Em 1992, foi publicado um artigo (BENOIST; FOULON; LABOURIE, 1992) provando que fluxos de contato Anosov com fibrados invariantes suaves são de fato algébricos . Neste trabalho procuramos generalizar o resultado obtido em (BENOIST; FOULON; LABOURIE, 1992). Para isso criamos uma definição adequada para ações de Rk contato Anosov, que generalizam a noção de fluxo de contato Anosov, e seguindo a estratégia de prova utilizada em (BENOIST; FOULON; LABOURIE, 1992), obtivemos uma generalização parcial deste resultado.

In this thesis, we define a new invariant of a Legendrian knot in a contact manifold using an open book decomposition supporting the contact structure. We define the support genus of a Legendrian knot L in a contact 3-manifold as the minimal genus of a page of an open book of M supporting the contact structure such that L sits on a page and the framings given by the contact structure and the page agree. For any topological link in 3-sphere we construct a planar open book decomposition whose monodromy is a product of positive Dehn twists such that the planar open book contains the link on its page. Using this, we show any topological link, in particular any knot in any 3-manifold M sits on a page of a planar open book decomposition of M and we show any null-homologous loose Legendrian knot in an overtwisted contact structure has support genus zero.

In this thesis, we write explicitly the open book decompositions of links of quotient surface singularities that support the corresponding unique Milnor fillable contact structures. The page-genus of these Milnor open books are minimal among all Milnor open books supporting the corresponding unique Milnor fillable contact structures. That minimal page-genus is called Milnor genus. In this thesis we also investigate whether the Milnor genus is equal to the support genus for links of quotient surface singularities. We show that for many types of the quotient surface singularities the Milnor genus is equal to the support genus of the corresponding contact structure. For the remaining we are able to find an upper bound for the support genus which would be a step forward in understanding these contact structures.

The problem of classifying the Anosov systems is of great interest in the theory of dynamical systems. The most important known examples are of algebraic nature and it has been conjectured on 1960s by S. Smale (SMALE, 1967) that these are in fact the only examples. This conjecture has been proved false for Anosov flows, where counter examples had been constructed for odd dimensional manifolds ((HANDEL; THURSTON, 1980) and (BARTHELMé et al., )). This non algebraic examples however are very pathological, and with some stronger hypothesis, for example, smoothness of the invariant bundles, the conjecture remains open. In 1992, it was published a paper (BENOIST; FOULON; LABOURIE, 1992) which proved that contact Anosov flows with smooth invariant bundles are in fact algebraic. In this monograph we seek to generalize the result obtained in (BENOIST; FOULON; LABOURIE, 1992). For this end, we create an adequate definition for contact Anosov Rk-actions, and following the proof strategy used in (BENOIST; FOULON; LABOURIE, 1992) we obtained a partial generalization of this result. / O problema da classificação dos sistemas Anosov são de grande interesse dentro da teoria dos sistemas dinâmicos. Os principais exemplos conhecidos são de natureza algébrica e foi levantada na década de 1960 a conjectura de que estes são os únicos exemplos (SMALE, 1967). Esta conjectura se mostrou falsa para fluxos Anosov (ações de R), onde foram construídos contraexemplos em variedades de dimensões impares ((HANDEL; THURSTON, 1980) e (BARTHELMé et al., )). Estes contra exemplos no entanto são de natureza patológica, e sob hipóteses um pouco mais fortes, por exemplo, suavidade dos fibrados invariantes, a conjectura permanece em aberto. Em 1992, foi publicado um artigo (BENOIST; FOULON; LABOURIE, 1992) provando que fluxos de contato Anosov com fibrados invariantes suaves são de fato algébricos . Neste trabalho procuramos generalizar o resultado obtido em (BENOIST; FOULON; LABOURIE, 1992). Para isso criamos uma definição adequada para ações de Rk contato Anosov, que generalizam a noção de fluxo de contato Anosov, e seguindo a estratégia de prova utilizada em (BENOIST; FOULON; LABOURIE, 1992), obtivemos uma generalização parcial deste resultado.