Lagrangian Formalism in Perturbed Nonlinear Klein-Gordon Equations

We develop an alternative approach to study the effect of the generic perturbation (in addition to explicitly considering the loss term) in the nonlinear Klein–Gordon equations. By a change of the variables that cancel the dissipation term we are able to write the Lagrangian density and then, calcul...

Descripción completa

Detalles Bibliográficos
Autores: Quintero, Niurka R., Zamora-Sillero, Elías
Tipo de recurso: artículo
Estado:Versión enviada para evaluación y publicación
Fecha de publicación:2004
País:España
Institución:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/42716
Acceso en línea:http://hdl.handle.net/11441/42716
https://doi.org/10.1016/j.physd.2004.06.007
Access Level:acceso abierto
Palabra clave:Collective coordinates
Solitary waves
Perturbed Nonlinear Klein-Gordon equations
Descripción
Sumario:We develop an alternative approach to study the effect of the generic perturbation (in addition to explicitly considering the loss term) in the nonlinear Klein–Gordon equations. By a change of the variables that cancel the dissipation term we are able to write the Lagrangian density and then, calculate the Lagrangian as a function of collective variables. We use the Lagrangian formalism together with the Rice Ansatz to derive the equations of motion of the collective coordinates (CCs) for the perturbed sine-Gordon (sG) and φ4 systems. For the N collective coordinates, regardless of the Ansatz used, we show that, for the nonlinear Klein–Gordon equations, this approach is equivalent to the Generalized Traveling Wave Ansatz (GTWA).