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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 S²Diego 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.
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Diamètre spectral et cohomologie symplectiqueMailhot, Pierre-Alexandre 08 1900 (has links)
Le groupe de difféomorphismes hamiltoniens à support compact d’une variété
symplectique admet une distance naturelle bi-invariante, d’après les
travaux de Viterbo, Schwarz, Oh, Frauenfelder et Schlenk, construite à partir
des invariants spectraux en homologie de Floer Hamiltonienne. Cette
distance, appelée la norme spectrale, s’est révélée être un outil fort utile en
topologie symplectique. Par contre, son diamètre reste inconnu en général.
En fait, pour les variétés symplectiques fermées, il n’existe même pas de
critère pour déterminer si la norme spectrale a un diamètre fini ou infini.
Il a été conjecturé que, pour les variétés symplectiquement asphériques, le
diamètre de la norme spectrale est infini.
Dans cette thèse, nous démontrons que pour tout domaine de Liouville, la
norme spectrale a un diamètre infini si et seulement si la cohomologie symplectique
du domaine de Liouville en question est non nulle. Ceci généralise
un résultat de Monzner-Vichery-Zapolsky et admet plusieurs applications
dans le cadre des variétés symplectiques fermées. En particulier, nous démontrons
que le produit de deux variétés symplectiquement asphériques a
un diamètre spectral infini. Plus généralement, nous démontrons que toute
variété symplectiquement asphérique contenant un domaine de Liouville incompressible
de codimension zéro avec cohomologie symplectique non nulle
doit avoir un diamètre spectral infini. / The group of compactly supported Hamiltonian diffeomorphisms of a symplectic
manifold is endowed with a natural bi-invariant distance, due to
Viterbo, Schwarz, Oh, Frauenfelder and Schlenk, coming from spectral invariants
in Hamiltonian Floer homology. This distance, called the spectral
norm, has found numerous applications in symplectic topology. However,
its diameter is still unknown in general. In fact, for closed symplectic manifolds
there is no unifying criterion for the diameter to be finite or infinite.
It has been conjectured that for closed symplectically aspherical manifolds,
the spectral norm has infinite diameter.
In this thesis, we prove that for any Liouville domain the spectral norm has
infinite diameter if and only if its symplectic cohomology does not vanish.
This generalizes a result of Monzner-Vichery-Zapolsky and has applications
in the setting of closed symplectic manifolds. For instance, we show that the
product of two closed symplectically aspherical manifold has an infinite spectral
diameter . More generally, we prove that any symplectically aspherical
manifold which contains an incompressible Liouville domain of codimension
zero with non-vanishing symplectic cohomology must have infinite spectral
diameter.
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