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arXiv · 2012.10967

A new model with solitary waves: solution, stability and quasinormal modes

Abstract

We construct solitary wave solutions in a $1+1$ dimensional massless scalar ($ϕ$) field theory with a specially chosen potential $V(ϕ)$. The equation governing perturbations about this solitary wave has an effective potential which is a simple harmonic well over a region, and a constant beyond. This feature allows us to ensure the stability of the solitary wave through the existence of bound states in the well, which can be found by semi-analytical methods. A further check on stability is performed through our search for quasi-normal modes (QNM) which are defined for purely outgoing boundary conditions. The time-domain profiles of the perturbations and the parametric variation of the QNM values are presented and discussed in some detail. Expectedly, a damped oscillatory temporal behaviour (ringdown) of the fluctuations is clearly seen through our analysis of the quasi-normal modes.

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Surajit Basak, Poulami Dutta Roy, Sayan Kar. 2021-06-03. A new model with solitary waves: solution, stability and quasinormal modes. https://doi.org/10.1140/epjp%2Fs13360-021-01544-3

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