Format:
vii, 94 Seiten
,
Diagramme
Content:
This work investigates diffusion in nonlinear Hamiltonian systems. The diffusion, more precisely subdiffusion, in such systems is induced by the intrinsic chaotic behavior of trajectories and thus is called chaotic diffusion''. Its properties are studied on the example of one- or two-dimensional lattices of harmonic or nonlinear oscillators with nearest neighbor couplings. The fundamental observation is the spreading of energy for localized initial conditions. Methods of quantifying this spreading behavior are presented, including a new quantity called excitation time. This new quantity allows for a more precise analysis of the spreading than traditional methods. Furthermore, the nonlinear diffusion equation is introduced as a phenomenologic description of the spreading process and a number of predictions on the density dependence of the spreading are drawn from this equation. Two mathematical techniques for analyzing nonlinear Hamiltonian systems are introduced. The first one is based on a scaling analysis of the Hamiltonian equation…
Note:
Dissertation Universität Potsdam 2012
Additional Edition:
Erscheint auch als Online-Ausgabe Mulansky, Mario Chaotic diffusion in nonlinear Hamiltonian systems 2013
Language:
English
Keywords:
Quantenchaos
;
Diffusion
;
Niederdimensionales System
;
Harmonischer Oszillator
;
Anharmonischer Oszillator
;
Nichtlineare Schrödinger-Gleichung
;
Computersimulation
;
Hochschulschrift
