Quasinormal modes in kink excitations and kink–antikink interactions: a toy model

• Published in: The European physical journal. C, Particles and fields Vol. 80; no. 5; pp. 1 - 15
• Main Authors: Campos, João G. F., Mohammadi, Azadeh
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.05.2020; Springer; Springer Nature B.V; SpringerOpen
• Subjects: Approximation; Astronomy; Astrophysics and Cosmology; Collisions; Elementary Particles; Energy; Excitation; Field theory; Fractals; Hadrons; Heavy Ions; Measurement Science and Instrumentation; Nuclear Energy; Nuclear Physics; Particle physics; Physics; Physics and Astronomy; Quantum Field Theories; Quantum Field Theory; Quantum mechanics; Radiation; Regular Article - Theoretical Physics; Scalars; Schrodinger equation; Square wells; Stability; String Theory
• ISSN: 1434-6044; 1434-6052
• DOI: 10.1140/epjc/s10052-020-7856-3

We study excitations and collisions of kinks in a scalar field theory where the potential has two minima with Z 2 symmetry. The field potential is designed to create a square well potential in the stability equation of the kink excitations. The stability equation is analogous to the Schrödinger equation, and therefore we use quantum mechanics techniques to study the system. We modify the square well potential continuously, which allows the excitation to tunnel and consequently turns the normal modes of the kink into quasinormal modes. We study the effect of this transition, leading to energy leak, on isolated kink excitations. Finally, we investigate kink–antikink collisions and the resulting scaling and fractal structure of the resonance windows considering both normal and quasinormal modes and compare the results.