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arXiv · 1805.03518

Vibrational modes of Q-balls

A. Kovtun·E. Nugaev·A. Shkerin
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Abstract

We study linear perturbations of classically stable Q-balls in theories admitting analytic solutions. Although the corresponding boundary value problem is non-Hermitian, the analysis of perturbations can also be performed analytically in certain regimes. We show that in theories with the flat potential, large Q-balls possess soft excitations. We also find a specific vibrational mode for Q-balls with a near-critical charge, where the perturbation theory for excitations can be developed. Comparing with the results on stability of Q-balls provides additional checks of our analysis.

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A. Kovtun, E. Nugaev, A. Shkerin. 2018-11-29. Vibrational modes of Q-balls. https://doi.org/10.1103/physrevd.98.096016

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