Sine-Gordon Equation: From Discrete to Continuum

In the present Chapter, we consider two prototypical Klein-Gordon models: the integrable sine- Gordon equation and the non-integrable φ4 model. We focus, in particular, on two of their prototypical solutions, namely the kink-like heteroclinic connections and the time-periodic, exponentially localize...

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Detalles Bibliográficos
Autores: Chirilus-Bruckner, Martina, Chong, Christopher, Kevrekidis, Panayotis G., Cuevas-Maraver, Jesús
Tipo de recurso: capítulo de libro
Estado:Versión enviada para evaluación y publicación
Fecha de publicación:2014
País:España
Institución:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/83341
Acceso en línea:https://hdl.handle.net/11441/83341
https://doi.org/10.1007/978-3-319-06722-3__2
Access Level:acceso abierto
Palabra clave:ϕ4 model
Anti-continuum limit
Breathers Continuum and discrete models
Kinks
Klein–Gordon lattices
Klein–Gordon PDEs
Nanopteron
PT-symmetry
Descripción
Sumario:In the present Chapter, we consider two prototypical Klein-Gordon models: the integrable sine- Gordon equation and the non-integrable φ4 model. We focus, in particular, on two of their prototypical solutions, namely the kink-like heteroclinic connections and the time-periodic, exponentially localized in space breather waveforms. Two limits of the discrete variants of these models are contrasted: on the one side, the analytically tractable original continuum limit, and on the opposite end, the highly discrete, so-called anti-continuum limit of vanishing coupling. Numerical computations are used to bridge these two limits, as regards the existence, stability and dynamical properties of the waves. Finally, a recent variant of this theme is presented in the form of PT -symmetric Klein-Gordon field theories and a number of relevant results are touched upon.