The Primitive Function of an Exact Symplectomorphism. Variational principles, Converse KAM Theory and the problems of determination and interpolation

[eng] We have divided this thesis in four parts: a) PART I: Exact symplectic geometry (introduction of the problems). This part contains the basic tools of symplectic geometry and outlines the four subjects that we have study along the thesis: the determination problem, the interpolation problem, th...

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Detalles Bibliográficos
Autor: Haro, Àlex
Tipo de recurso: tesis doctoral
Estado:Versión publicada
Fecha de publicación:1998
País:España
Institución:Universidad de Barcelona
Repositorio:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/42094
Acceso en línea:https://hdl.handle.net/2445/42094
http://www.tdx.cat/TDX-1030109-115035
http://hdl.handle.net/10803/2116
Access Level:acceso abierto
Palabra clave:Topologia diferencial
Geometria diferencial
Òrbites
Differential topology
Differential geometry
Orbits
Descripción
Sumario:[eng] We have divided this thesis in four parts: a) PART I: Exact symplectic geometry (introduction of the problems). This part contains the basic tools of symplectic geometry and outlines the four subjects that we have study along the thesis: the determination problem, the interpolation problem, the variational problem and the breakdown problem. b) PART II: On the standard symplectic manifold (analytical part). We recall the necessary tools to work on R(d) x R(d). That is we perform a coordinate treatment of the results. First of all we relate different kinds of generating functions to the primitive function and later we solve formally the determination problem. Then we introduce different variational principles: for fixed points, periodic orbits and orbital segments. Their invariance under certain kind of transformations of phase space is proved, and we interpret physically such results. Finally we give the basic properties of invariant exact Lagrangian graphs obtaining at last that if our graph is minimizing then its orbits are minimizing. c) PART III: On the cotangent bundle (geometrical part). The first three chapters are similar to the three previous ones with the difference that we do an intrinsic treatment of the results by considering any cotangent bundle. The fourth chapter in this part deals with the solution of the interpolation problem given in analytic set up. d) PART IV: Converse KAM theory (numerical part). The last part deals with the applications to converse Kolmogorv-Arnold-Moser (KAM) theory. First of all we give a small list of different examples that we shall study later. Then we generalize converse KAM theory and we related it to the Lipschitz theory by Birkhoff and Herman. Then we perform our variational Greene method and apply it to different examples. Also we study numerically the Aubry-Mather sets in higher dimensions. After this we apply our methods to the rotational standard map that is a symplectic skew product. Then we give some ideas about the geometrical obstructions for existence of invariant tori showing them with a simple example. We also find some known Birkhoff normal forms using our methods. Finally we explain briefly how our theory can be used for arbitrary Lagrangian foliations.