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arXiv · 2611.01826

Vanishing Island: Spectral Criticality in Boson Stars

Bo-Xuan Ge
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Abstract

We identify a cusp-type endpoint at which a finite radially stable region of solitonic boson stars disappears. Two fundamental radial zero-mode boundaries coalesce there, while the constrained quadratic stiffness and cubic coefficient vanish and the quartic coefficient remains finite and non-zero. The soft radial mode obeys \(Ω_{\mathrm{soft}}\propto (σ_{\mathrm{cusp}}-σ)^{1/2}\), revealing a divergent linear timescale at the endpoint. The same critical structure persists under the tested deformation of the scalar self-interaction.

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Bo-Xuan Ge. 2026-11-01. Vanishing Island: Spectral Criticality in Boson Stars. https://arxiv.org/abs/2611.01826

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