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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Propriedades de dinâmica hamiltoniana em níveis de energia convexos de R4 / Properties of the hamiltonian dynamics in convex energy levels of R4

Alves, Marcelo Ribeiro de Resende 25 May 2011 (has links)
A existência de seções globais para uxos é de central importância na teoria de sistemas dinâmicos, pois uma seção global simplica o estudo da dinâmica de um uxo reduzindo-o ao estudo da dinâmica de um difeomorsmo. Apresentamos detalhadamente a construção feita Hofer, Zehnder e Wysocki (em \'\'The dynamics on a strictly convex energy surface in R4\'\') de uma seção global para o uxo Hamiltoniano restrito a um nível de energia convexo em R4 . Uma importante consequência da existência dessa seção global é que o uxo Hamiltoniano restrito a um nível de energia convexo em R4 tem 2 ou innitas órbitas periódicas. Essa construção utiliza-se da teoria de curvas pseudo-holomorfas em simplectizações de variedades de contato desenvolvida pelos mesmos autores. Os argumentos apresentados também dão uma nova prova da Conjectura de Weinstein para formas de contato tight em S3 . / The existence of global surfaces of section to ows is of central importance in the theory of dynamical systems, as a global surface of section simplies the study of the dynamics of a ow reducing it to the study of the dynamics of a dieomorphism. We present in detail the construction due to Hofer, Wysocki and Zehnder (in \'\'The dynamics on a strictly convex energy surface in R4\'\') of a global surface of section for the Hamiltonian ow restricted to a convex energy level in R4 . An important consequence of the existence of the global surface of section is that the Hamiltonian ow restricted to a convex energy level in R4 has either 2 or innitely many periodic orbits. This construction makes use of the theory of pseudo-holomorphic curves in symplectizations of contact manifolds developed by the same authors. The arguments also give a new proof of Weinstein conjecture for tight contact forms in S3 .
2

Propriedades de dinâmica hamiltoniana em níveis de energia convexos de R4 / Properties of the hamiltonian dynamics in convex energy levels of R4

Marcelo Ribeiro de Resende Alves 25 May 2011 (has links)
A existência de seções globais para uxos é de central importância na teoria de sistemas dinâmicos, pois uma seção global simplica o estudo da dinâmica de um uxo reduzindo-o ao estudo da dinâmica de um difeomorsmo. Apresentamos detalhadamente a construção feita Hofer, Zehnder e Wysocki (em \'\'The dynamics on a strictly convex energy surface in R4\'\') de uma seção global para o uxo Hamiltoniano restrito a um nível de energia convexo em R4 . Uma importante consequência da existência dessa seção global é que o uxo Hamiltoniano restrito a um nível de energia convexo em R4 tem 2 ou innitas órbitas periódicas. Essa construção utiliza-se da teoria de curvas pseudo-holomorfas em simplectizações de variedades de contato desenvolvida pelos mesmos autores. Os argumentos apresentados também dão uma nova prova da Conjectura de Weinstein para formas de contato tight em S3 . / The existence of global surfaces of section to ows is of central importance in the theory of dynamical systems, as a global surface of section simplies the study of the dynamics of a ow reducing it to the study of the dynamics of a dieomorphism. We present in detail the construction due to Hofer, Wysocki and Zehnder (in \'\'The dynamics on a strictly convex energy surface in R4\'\') of a global surface of section for the Hamiltonian ow restricted to a convex energy level in R4 . An important consequence of the existence of the global surface of section is that the Hamiltonian ow restricted to a convex energy level in R4 has either 2 or innitely many periodic orbits. This construction makes use of the theory of pseudo-holomorphic curves in symplectizations of contact manifolds developed by the same authors. The arguments also give a new proof of Weinstein conjecture for tight contact forms in S3 .
3

Existência implicada de órbitas periódicas para fluxos de Reeb em S¹ x S² / Implied existence of closed orbits for the Reeb flows in S¹ x S²

Salazar, Diego Alfonso Sandoval 29 June 2017 (has links)
Consideramos o fluxo de Reeb associado a uma forma de contato em S¹ x S² que induz a estrutura de contato tight. Assumimos que o fluxo admite um par de órbitas periódicas L0 e L1 cujo link L = L0 L1 é transversalmente isotópico a ( S¹ x )( S¹ x ), em que n = (0,0,1) e s = (0,0,1) são os pólos norte e sul de S², respectivamente. O objetivo é provar que, nestas condições, existem infinitas órbitas periódicas no complementar desse link cujas classes de homotopia no complementar do link são prescritas de acordo com os números de rotação de L0 e L1. / We consider the Reeb flow associated to a contact form on S¹ x S² which induces a tight contact structure. We assume that the flow admits a pair of closed orbits L0 and L1 whose link L = L0 L1 is transversely isotopic to (S¹ x)(S¹ x), where n = (0,0,1) and s =(0,0,1) are the north and south poles of S², respectively. The main goal is to prove that, under these conditions, there exit infinitely many closed orbits in the complement of this link whose homotopy classes in the complement of this link are prescribed according to the rotation numbers of L0 and L1.
4

Sobre fluxos de Reeb tri-dimensionais: existência implicada de órbitas periódicas e uma caracterização dinâmica do toro sólido. / On three-dimensional Reeb flows: implied existence of periodic orbits and a dynamical characterization of the solid torus

Silva, André Vanderlinde da 29 October 2014 (has links)
Neste trabalho, estudamos a dinâmica de Reeb associada a uma forma de contato $\\lambda$ definida numa 3-variedade compacta e conexa M. Assumimos que $\\lambda$ é tight e a primeira classe de Chern da estrutura de contato $\\xi=\\ker\\lambda$ se anula sobre $\\pi_2(M)$. No nosso primeiro resultado, supomos que M é fechada e existe uma órbita fechada L do fluxo de Reeb que é um p-nó trivial com número de auto-enlaçamento $-1/p$. Supomos, além disso, que o número de rotação transversal da p-ésima iterada de L é estritamente menor do que 1. Nestas condições, provamos que existe uma órbita fechada (de Reeb) contrátil geometricamente distinta de L e não-enlaçada em L cujo número de rotação transversal é 1. Apresentamos também uma versão deste resultado para o caso em que M é uma 3-variedade cujo bordo é difeomorfo a um toro e invariante pelo fluxo de Reeb e não existem órbitas fechadas contidas no bordo. Nosso segundo resultado é uma caracterização dinâmica do toro sólido. Seja $\\lambda$ uma forma de contato não-degenerada definida em uma 3-variedade M cujo bordo é difeomorfo a um toro e invariante pelo fluxo de Reeb. Se o fluxo de Reeb satisfaz certas hipóteses de torção sobre o bordo, então ou existe uma órbita fechada contrátil com índice de Conley-Zehnder 2 ou M é folheada por discos transversais ao campo de Reeb. Neste último caso, M é difeomorfa a um toro sólido e existe uma órbita fechada não-contrátil em M que é ponto fixo da aplicação de retorno induzida pela folheação. / In this work, we study the Reeb dynamics associated to a tight contact form $\\lambda$ defined on a compact, connected 3-manifold M. Suppose that the first Chern class of $\\xi=\\ker\\lambda$ vanish on $\\pi_2(M)$. In our first result, we assume that M is closed and there exists a closed Reeb orbit L which is a p-unknotted, has self-linking number $-1/p$ and the transverse rotation number of the p-th iterate of L is less than 1. Under these conditions, we verify that there exists a contractible closed Reeb orbit which is geometrically distinct from L and not linked to L with transverse rotation number 1. We also prove a version of this result when M is a compact 3-manifold M whose boundary is diffeomorphic to a torus and invariant by the flow and, moreover, there does not exist closed Reeb orbits on the boundary. Our second result is a dynamical characterization of the solid torus. We assume that $\\lambda$ is a contact form on a compact 3-manifold M whose boundary is diffeomorphic to a torus. Under the hypothesis of $\\lambda$ being non-degenerate, if the flow is tangent to $\\partial M$ and satisfies some twist conditions on the boundary, then either there exists a contractible closed Reeb orbit which has Conley-Zehnder index 2 or M is foliated by disks transverse to the Reeb flow. In this last case, we see that M is diffeomorphic to a solid torus and there exists a non-contractible closed Reeb orbit M which is a fixed point of the return map induced by the foliation.
5

Sobre fluxos de Reeb tri-dimensionais: existência implicada de órbitas periódicas e uma caracterização dinâmica do toro sólido. / On three-dimensional Reeb flows: implied existence of periodic orbits and a dynamical characterization of the solid torus

André Vanderlinde da Silva 29 October 2014 (has links)
Neste trabalho, estudamos a dinâmica de Reeb associada a uma forma de contato $\\lambda$ definida numa 3-variedade compacta e conexa M. Assumimos que $\\lambda$ é tight e a primeira classe de Chern da estrutura de contato $\\xi=\\ker\\lambda$ se anula sobre $\\pi_2(M)$. No nosso primeiro resultado, supomos que M é fechada e existe uma órbita fechada L do fluxo de Reeb que é um p-nó trivial com número de auto-enlaçamento $-1/p$. Supomos, além disso, que o número de rotação transversal da p-ésima iterada de L é estritamente menor do que 1. Nestas condições, provamos que existe uma órbita fechada (de Reeb) contrátil geometricamente distinta de L e não-enlaçada em L cujo número de rotação transversal é 1. Apresentamos também uma versão deste resultado para o caso em que M é uma 3-variedade cujo bordo é difeomorfo a um toro e invariante pelo fluxo de Reeb e não existem órbitas fechadas contidas no bordo. Nosso segundo resultado é uma caracterização dinâmica do toro sólido. Seja $\\lambda$ uma forma de contato não-degenerada definida em uma 3-variedade M cujo bordo é difeomorfo a um toro e invariante pelo fluxo de Reeb. Se o fluxo de Reeb satisfaz certas hipóteses de torção sobre o bordo, então ou existe uma órbita fechada contrátil com índice de Conley-Zehnder 2 ou M é folheada por discos transversais ao campo de Reeb. Neste último caso, M é difeomorfa a um toro sólido e existe uma órbita fechada não-contrátil em M que é ponto fixo da aplicação de retorno induzida pela folheação. / In this work, we study the Reeb dynamics associated to a tight contact form $\\lambda$ defined on a compact, connected 3-manifold M. Suppose that the first Chern class of $\\xi=\\ker\\lambda$ vanish on $\\pi_2(M)$. In our first result, we assume that M is closed and there exists a closed Reeb orbit L which is a p-unknotted, has self-linking number $-1/p$ and the transverse rotation number of the p-th iterate of L is less than 1. Under these conditions, we verify that there exists a contractible closed Reeb orbit which is geometrically distinct from L and not linked to L with transverse rotation number 1. We also prove a version of this result when M is a compact 3-manifold M whose boundary is diffeomorphic to a torus and invariant by the flow and, moreover, there does not exist closed Reeb orbits on the boundary. Our second result is a dynamical characterization of the solid torus. We assume that $\\lambda$ is a contact form on a compact 3-manifold M whose boundary is diffeomorphic to a torus. Under the hypothesis of $\\lambda$ being non-degenerate, if the flow is tangent to $\\partial M$ and satisfies some twist conditions on the boundary, then either there exists a contractible closed Reeb orbit which has Conley-Zehnder index 2 or M is foliated by disks transverse to the Reeb flow. In this last case, we see that M is diffeomorphic to a solid torus and there exists a non-contractible closed Reeb orbit M which is a fixed point of the return map induced by the foliation.
6

Existência implicada de órbitas periódicas para fluxos de Reeb em S¹ x S² / Implied existence of closed orbits for the Reeb flows in S¹ x S²

Diego Alfonso Sandoval Salazar 29 June 2017 (has links)
Consideramos o fluxo de Reeb associado a uma forma de contato em S¹ x S² que induz a estrutura de contato tight. Assumimos que o fluxo admite um par de órbitas periódicas L0 e L1 cujo link L = L0 L1 é transversalmente isotópico a ( S¹ x )( S¹ x ), em que n = (0,0,1) e s = (0,0,1) são os pólos norte e sul de S², respectivamente. O objetivo é provar que, nestas condições, existem infinitas órbitas periódicas no complementar desse link cujas classes de homotopia no complementar do link são prescritas de acordo com os números de rotação de L0 e L1. / We consider the Reeb flow associated to a contact form on S¹ x S² which induces a tight contact structure. We assume that the flow admits a pair of closed orbits L0 and L1 whose link L = L0 L1 is transversely isotopic to (S¹ x)(S¹ x), where n = (0,0,1) and s =(0,0,1) are the north and south poles of S², respectively. The main goal is to prove that, under these conditions, there exit infinitely many closed orbits in the complement of this link whose homotopy classes in the complement of this link are prescribed according to the rotation numbers of L0 and L1.
7

Sistemas de seções transversais próximos a níveis críticos de sistemas Hamiltonianos em $\\mathbb{R}^4$ / Systems of transverse sections near critical levels of Hamiltonian systems in $\\mathbb R ^4$

Paulo, Naiara Vergian de 10 June 2014 (has links)
Neste trabalho estudamos dinâmica Hamiltoniana em $\\mathbb{R}^4$ restrita a níveis de energia próximos a níveis críticos. Mais precisamente, consideramos uma função Hamiltoniana $H: \\mathbb{R}^4 \\to \\mathbb{R}$ que possui um ponto de equilíbrio do tipo sela-centro $p_c \\in H^{-1}(0)$ e assumimos que $p_c$ pertence a um conjunto singular estritamente convexo $S_0 \\subset H^{-1}(0)$. Então, mostramos que os níveis de energia $H^{-1}(E)$, com $E>0$ suficientemente pequeno, contêm uma $3$-bola fechada $S_E$ próxima a $S_0$ que admite um sistema de seções transversais $F_E$, chamado folheação $2-3$. $F_E$ é uma folheação singular de $S_E$ com conjunto singular formado por duas órbitas periódicas $P_{2,E}\\subset \\partial S_E$ e $P_{3,E}\\subset S_E\\setminus \\partial S_E$. A órbita $P_{2,E}$ é hiperbólica dentro do nível de energia $H^{-1}(E)$, pertence à variedade central do sela-centro $p_c$, tem índice de Conley-Zehnder $2$ e é o limite assintótico de dois planos rígidos de $F_E$ que, unidos com $P_{2,E}$, constituem a $2$-esfera $\\partial S_E$. A órbita $P_{3,E}$ tem índice de Conley-Zehnder $3$ e é o limite assintótico de uma família a um parâmetro de planos de $F_E$ contida em $S_E\\setminus \\partial S_E$. Um cilindro rígido conectando as órbitas $P_{3,E}$ e $P_{2,E}$ completa a folheação $F_E$. Uma vez que $F_E$ é um sistema de seções transversais, todas as suas folhas regulares são transversais ao fluxo Hamiltoniano de $H$. Como consequência da existência de uma tal folheação em $S_E$, concluímos que a órbita hiperbólica $P_{2,E}$ admite pelo menos uma órbita homoclínica contida em $S_E \\setminus \\partial S_E$. / In this work we study Hamiltonian dynamics in $\\mathbb R ^4$ restricted to energy levels close to critical levels. More precisely, we consider a Hamiltonian function $H:\\mathbb R ^4 \\to \\mathbb R$ containing a saddle-center equilibrium point $p_c \\in H^ -1 (0)$ and we assume that $p_c$ lies on a strictly convex singular set $S_0 \\subset H^ -1 (0)$. Then we prove that the energy levels $H^ -1 (E)$, with $E>0$ sufficiently small, contain a closed $3$-ball $S_E$ near $S_0$ admitting a system of transverse sections $F_E$, called a $2-3$ foliation. $F_E$ is a singular foliation of $S_E$ and its singular set consists of two periodic orbits $P_{2,E}\\subset \\partial S_E$ and $P_{3,E}\\subset S_E\\setminus \\partial S_E$. The orbit $P_{2,E}$ is hyperbolic inside the energy level $H^ -1 (E)$, lies on the center manifold of the saddle-center $p_c$, has Conley-Zehnder index $2$ and is the asymptotic limit of two rigid planes of $F_E$, which compose the $2$-sphere $S_E$ together with $P_{2,E}$. The orbit $P_{3,E}$ has Conley-Zehnder index $3$ and is the asymptotic limit of a one parameter family of planes of $F_E$ contained in $S_E \\setminus \\partial S_E$. A rigid cylinder connecting the orbits $P_{3,E}$ and $P_{2,E}$ completes the foliation $F_E$. Since $F_E$ is a system of transverse sections, all its regular leaves are transverse to the Hamiltonian flow of $H$. As a consequence of the existence of such foliation in $S_E$, we conclude that the hyperbolic orbit $P_{2,E}$ admits at least one homoclinic orbit contained in $S_E\\setminus \\partial S_E$.
8

Sistemas de seções transversais próximos a níveis críticos de sistemas Hamiltonianos em $\\mathbb{R}^4$ / Systems of transverse sections near critical levels of Hamiltonian systems in $\\mathbb R ^4$

Naiara Vergian de Paulo 10 June 2014 (has links)
Neste trabalho estudamos dinâmica Hamiltoniana em $\\mathbb{R}^4$ restrita a níveis de energia próximos a níveis críticos. Mais precisamente, consideramos uma função Hamiltoniana $H: \\mathbb{R}^4 \\to \\mathbb{R}$ que possui um ponto de equilíbrio do tipo sela-centro $p_c \\in H^{-1}(0)$ e assumimos que $p_c$ pertence a um conjunto singular estritamente convexo $S_0 \\subset H^{-1}(0)$. Então, mostramos que os níveis de energia $H^{-1}(E)$, com $E>0$ suficientemente pequeno, contêm uma $3$-bola fechada $S_E$ próxima a $S_0$ que admite um sistema de seções transversais $F_E$, chamado folheação $2-3$. $F_E$ é uma folheação singular de $S_E$ com conjunto singular formado por duas órbitas periódicas $P_{2,E}\\subset \\partial S_E$ e $P_{3,E}\\subset S_E\\setminus \\partial S_E$. A órbita $P_{2,E}$ é hiperbólica dentro do nível de energia $H^{-1}(E)$, pertence à variedade central do sela-centro $p_c$, tem índice de Conley-Zehnder $2$ e é o limite assintótico de dois planos rígidos de $F_E$ que, unidos com $P_{2,E}$, constituem a $2$-esfera $\\partial S_E$. A órbita $P_{3,E}$ tem índice de Conley-Zehnder $3$ e é o limite assintótico de uma família a um parâmetro de planos de $F_E$ contida em $S_E\\setminus \\partial S_E$. Um cilindro rígido conectando as órbitas $P_{3,E}$ e $P_{2,E}$ completa a folheação $F_E$. Uma vez que $F_E$ é um sistema de seções transversais, todas as suas folhas regulares são transversais ao fluxo Hamiltoniano de $H$. Como consequência da existência de uma tal folheação em $S_E$, concluímos que a órbita hiperbólica $P_{2,E}$ admite pelo menos uma órbita homoclínica contida em $S_E \\setminus \\partial S_E$. / In this work we study Hamiltonian dynamics in $\\mathbb R ^4$ restricted to energy levels close to critical levels. More precisely, we consider a Hamiltonian function $H:\\mathbb R ^4 \\to \\mathbb R$ containing a saddle-center equilibrium point $p_c \\in H^ -1 (0)$ and we assume that $p_c$ lies on a strictly convex singular set $S_0 \\subset H^ -1 (0)$. Then we prove that the energy levels $H^ -1 (E)$, with $E>0$ sufficiently small, contain a closed $3$-ball $S_E$ near $S_0$ admitting a system of transverse sections $F_E$, called a $2-3$ foliation. $F_E$ is a singular foliation of $S_E$ and its singular set consists of two periodic orbits $P_{2,E}\\subset \\partial S_E$ and $P_{3,E}\\subset S_E\\setminus \\partial S_E$. The orbit $P_{2,E}$ is hyperbolic inside the energy level $H^ -1 (E)$, lies on the center manifold of the saddle-center $p_c$, has Conley-Zehnder index $2$ and is the asymptotic limit of two rigid planes of $F_E$, which compose the $2$-sphere $S_E$ together with $P_{2,E}$. The orbit $P_{3,E}$ has Conley-Zehnder index $3$ and is the asymptotic limit of a one parameter family of planes of $F_E$ contained in $S_E \\setminus \\partial S_E$. A rigid cylinder connecting the orbits $P_{3,E}$ and $P_{2,E}$ completes the foliation $F_E$. Since $F_E$ is a system of transverse sections, all its regular leaves are transverse to the Hamiltonian flow of $H$. As a consequence of the existence of such foliation in $S_E$, we conclude that the hyperbolic orbit $P_{2,E}$ admits at least one homoclinic orbit contained in $S_E\\setminus \\partial S_E$.
9

Homologie instanton-symplectique : somme connexe, chirurgie de Dehn, et applications induites par cobordismes / Symplectic instanton homology : connected sum, Dehn surgery, and maps from cobordisms

Cazassus, Guillem 12 April 2016 (has links)
L'homologie instanton-symplectique est un invariant associé à une variété de dimension trois close orientée, qui a été dé?ni par Manolescu et Woodward, et qui correspond conjecturalement à une version symplectique d'une homologie des instantons de Floer. Dans cette thèse nous étudions le comportement de cet invariant sous l'effet d'une somme connexe, d'une chirurgie de Dehn, et d'un cobordisme de dimension quatre. Nous établissons une formule de Künneth pour la somme connexe : si Y et Y' désignent deux variétés closes orientées de dimension trois, l'homologie instanton-symplectique associée à leur somme connexe est isomorphe à la somme directe du produit tensoriel de leurs groupes d'homologie instantonsymplectique respectifs, et de leur produit de torsion (après décalage des degrés). Nous définissons des versions tordues de cette homologie, et prouvons un analogue de la suite exacte de Floer, reliant les groupes associés à une triade de chirurgie. Cette suite exacte nous permet de calculer le rang des groupes associés à des familles de variétés, notamment les revêtements doubles ramifiés d'entrelacs quasi-alternés, des chirurgies entières de grande pente le long de certains noeuds, ainsi que certaines variétés obtenues par plombage de fibrés en disques au-dessus de sphères. Nous définissons enfin des invariants pour des cobordismes de dimension 4 prenant la forme d'applications entre groupes d'homologie instantonsymplectique des bords, et prouvons que deux des morphismes intervenant dans la suite exacte de chirurgie s'interprètent comme de telles applications, associées aux cobordismes d'attachement d'anses. Nous donnons également un critère d'annulation pour de telles applications associées à des éclatements. / Symplectic instanton homology is an invariant for closed oriented three-manifolds, defined by Manolescu and Woodward, which conjecturally corresponds to a symplectic version of a variant of Floer's instanton homology. In this thesis we study the behaviour of this invariant under connected sum, Dehn surgery, and four-dimensional cobordisms. We prove a Künneth-type formula for the connected sum: let Y and Y' be two closed oriented three-manifolds, we show that the symplectic instanton homology of their connected sum is isomorphic to the direct sum of the tensor product of their symplectic instanton homology, and a shift of their torsion product. We define twisted versions of this homology, and then prove an analog of the Floer exact sequence, relating the invariants of a Dehn surgery triad. We use this exact sequence to compute the rank of the groups associated to branched double covers of quasi-alternating links, some plumbings of disc bundles over spheres, and some integral Dehn surgeries along certain knots. We then define invariants for four dimensional cobordisms as maps between the symplectic instanton homology of the two boundaries. We show that among the three morphisms in the surgery exact sequence, two are such maps, associated to the handle-attachment cobordisms. We also give a vanishing criteria for such maps associated to blow-ups.
10

Hamiltonian Floer theory on surfaces

Connery-Grigg, Dustin 12 1900 (has links)
Dans cette thèse, nous développons de nouveaux outils pour relier les dynamiques qualitatives des systèmes hamiltoniens sur des surfaces aux propriétés algèbriques de leurs complexes de Floer - un objet algébrique qui encode l'information sur la façon dont les orbites 1-périodiques d'un système sont reliées par des cylindres satisfaisant une équation différentielle partielle elliptique appelée l'équation de Floer. L'idée principale est de considérer --- pour un hamiltonian \(H \in C^\infty(S^1 \times \Sigma)\) sur une surface symplectique \((\Sigma, \omega)\) --- les graphes des orbites contractiles 1-périodiques de l'isotopie \((\phi^H_t)_{t \in [0,1]}\) comme définissant une tresse \(P^H\) dans \(S^1 \times \Sigma\). En choisissant des capuchons pour chacune de ces orbites 1-périodiques, nous obtenons un objet que nous appelons une tresse encapuchonnée \(\hat{P}^H\), qui est muni d'une fonction d'indexation \(\mu_{CZ}: \hat{P}^H \rightarrow \mathbb{Z}\) obtenue en assignant à chaque brin encapuchonné l'indice de Conley-Zehnder de l'orbite encapuchonnée associée. L'idée est alors de s'interroger sur la relation entre l'information topologique encodée dans la tresse encapuchonnée indexée \((\hat{P}^H,\mu_{CZ})\) et la structure du complexe de Floer \(CF_*(H,J)\) pour une structure presque complexe générique \(J\). À cette fin, nous aurons recours à: un nouvel invariant relatif pour les paires de tresses encapuchonnées que nous appelons le nombre d'enlacement homologique, un cercle d'idées concernant le comportement asymptotique des courbes pseudo-holomorphes développé par Hofer-Wysocki-Zehnder dans leur série d'articles [8], [10], [12] et aussi [11] (ainsi qu'un raffinement supplémentaire dans le cas relatif dû à Siefring dans [32]), et une nouvelle technique en basses dimensions pour la construction de morphismes de continuation de Floer qui ont un comportement prescrit. En conséquence de ces techniques, nous établissons l'existence --- pour des systèmes hamiltoniens génériques sur une surface fermée arbitraire --- de certaines feuilletages singulières spéciaux sur \(S^1 \times \Sigma\) dont le comportement est étroitement lié à la fois à la dynamique sous-jacente et à la structure du complexe de Floer du système. La construction de tels feuilletages dans le cas particulier des pseudo-rotations d'un disque, par des méthodes très différentes des nôtres, a été au coeur des progrès significatifs récents de Bramham dans [3] sur une célèbre question de Katok concernant les systèmes conservatifs de basse dimension et d'entropie nulle. Ces feuilletages fournissent également, pour les systèmes hamiltoniens lisses génériques, une construction Floer-théorique des feuilletages positivement transversaux sur \(\Sigma\) qui ont été construits originellement (pour les homéomorphismes de surface généraux) par Le Calvez à travers d'une extension substantielle de la théorie de Brouwer classique pour les homéomorphismes de surface dans [16]. En plus de fournir un pont géométrique entre la dynamique d'une isotopie hamiltonienne et l'information algébrique contenue dans son complexe de Floer, les techniques développées dans cette thèse permettent également de donner une caractérisation --- purement en termes de la dynamique de l'isotopie hamiltonienne sous-jacente --- des cycles de Floer dans \(CF_*(H,J)\) qui représentent la classe fondamentale de la surface et qui de plus se trouvent dans l'image d'un morphisme de PSS au niveau des chaines. Finalement, ces techniques permettent de définir une nouvelle famille d'invariants d'un système hamiltonien (sur une variété symplectique arbitraire) qui se comporte formellement de manière similaire à une famille bien étudiée de tels invariants connue comme les invariants spectraux de Oh-Schwarz. L'avantage de nos nouveaux invariants est que nous sommes capable de calculer explicitement les plus importants d'entre eux pour des systèmes hamiltoniens génériques sur des surfaces arbitraires, ce uniquement en termes de topologie relative des orbites périodiques du système (avec leurs indices de Conley-Zehnder). Ceci généralise un résultat de Humilière-Le Roux-Seyfaddini dans [13] dans lequel ils ont donné une caractérisation dynamique du principal invariant spectral de Oh-Schwarz dans le cas de systèmes hamiltoniens autonomes sur des surfaces de genre positif. / In this thesis, we develop novel tools for relating the qualitative dynamics of Hamiltonian systems on surfaces to the algebraic properties of their Floer complexes --- an algebraic object which encodes information about the ways in which a system’s 1-periodic orbits are connected by cylinders satisfying an elliptic partial differential equation known as Floer’s equation. The main idea is to consider --- for a generic Hamiltonian \(H \in C^\infty(S^1 \times \Sigma)\) on a symplectic surface \((\Sigma, \omega)\) --- the graphs of the contractible time-1 periodic orbits of the isotopy \((\phi^H_t)_{t \in [0,1]}\) as defining a braid \(P^H\) in \(S^1 \times \Sigma\). Upon choosing cappings for each such 1-periodic orbit, we obtain an object which we term a capped braid \(\hat{P}^H\), which comes equipped with an indexing function \(\mu_{CZ}: \hat{P}^H \rightarrow \mathbb{Z}\) given by assigning to each (capped) strand of the braid the Conley-Zehnder index of the associated capped orbit. The idea is then to enquire into the relation of the topological information encoded in the indexed capped braid \((\hat{P}^H,\mu_{CZ})\) and the structure of the Floer complex \(CF_*(H,J)\) for a generic \(J\). The main tools employed to this end are: a novel relative invariant for pairs of capped braids which we term the homological linking number, a circle of ideas about the asymptotic behaviour of pseudo-holomorphic curves pioneered by Hofer-Wysocki-Zehnder in their series of papers [8], [10], [12] as well as in [11] (along with a further refinement to the relative case by Siefring in [32]), and a novel technique for the construction of regular Floer continuation maps in low-dimensions having prescribed behaviour. As a consequence of these techniques, we establish the existence --- for generic Hamiltonian systems on an arbitrary closed surface \(\Sigma\) --- of certain special singular foliations on \(S^1 \times \Sigma\) whose behaviour is tightly related to both the underlying dynamics, as well as the structure of the system’s Floer complex. The construction of such foliations (by very different methods) in the particular case of pseudo-rotations on a disk was the crux of Bramham’s recent significant progress in [3] on a famous question due to Katok about low-dimensional conservative systems with vanishing entropy. These foliations also provide, for generic smooth Hamiltonian systems, 7 a Floer-theoretic construction of the positively transverse foliations on \(\Sigma\) which were originally constructed (for general surface homeomorphisms) by Le Calvez through a significant extension of classical Brouwer theory for surface homeomorphisms in [16]. In addition to providing a geometric bridge between the dynamics of a Hamiltonian isotopy and the algebraic information contained in its associated Floer complex, the techniques developed in this dissertation also permit a characterization --- purely in terms of the dynamics of the underlying Hamiltonian isotopy --- of those Floer cycles in \(CF_*(H,J)\) which represent the fundamental class of the surface, and which moreover lie in the image of some chain-level PSS map. Finally, these techniques permit the definition of a new family of invariants of a Hamiltonian system (on an arbitrary symplectic manifold) which behave formally similarly to a well-studied family of such invariants known as ‘Oh-Schwarz spectral invariants’ (and which agree with them in all known cases). The advantage of these novel spectral invariants is that we are able to explicitly compute the most important of these spectral invariants for generic Hamiltonian systems on arbitrary surfaces purely in terms of the relative topology of the system’s periodic orbits (together with their Conley-Zehnder indices). This considerably generalizes a result by Humilière-Le Roux-Seyfaddini in [13] in which they gave a dynamical characterization of the main Oh-Schwarz spectral invariant in the case of time-independent Hamiltonian systems on surfaces with positive genus.

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